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Mainstream media and first responders on the day of 9/11 - PROOFS!

No facts? have you read what I posted? By the way Zyxius do yourself a favour either call by the name I have posted or feel free to have a ban. I have seen the crap you peddle on many websites and seen the bile you spill there and many other places.

BTW Dabong take a look at some of the people advocating Conspiracies. You can see a few
in the penn and teller video,
 
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November 28, 2006
The Age of Irrationality
The 9/11 Conspiracists and the Decline of the Anmerican Left

By ALEXANDER COCKBURN

Where was the American left in the campaign that ended in recapture of both houses of Congress by the Democrats on November 7, 2006? Was it in the streets, fomenting opposition to the war in Iraq? Not at all. The antiwar movement has been inert for months. When I was asked to give the keynote speech at a rare antiwar rally in my local town of Eureka, northern California, in early October, three of my five fellow orators didn't deign to mention the war at all. Instead they numbed the audience and sharply diminished its size with interminable dissections of the 9/11/2001 attacks on the World Trade Center towers and the Pentagon. Their aim? To argue that the attacks were an "inside job", organized by Bush and Cheney or (a frequent variation on the theme) darker powers, for whom Bush and Cheney are the mere errand boys.

Five years after the attacks, 9/11 conspiracism has now penetrated deep into the American left. It is also widespread on the libertarian and populist right, but that is scarcely surprising, since the American populist right instinctively mistrusts government to a far greater degree than the left, and matches conspiracies to its demon of preference, whether the Internal Revenue Service, the Federal Emergency Management Agency, Black Helicopters or the Jews.

These days a dwindling number of leftists learn their political economy from Marx via the small, mostly Trotskyist groupuscules. Into the theoretical and strategic void has crept a diffuse, peripatic conspiracist view of the world that tends to locate ruling class devilry not in the crises of capital accumulation, or the falling rate of profit, or inter-imperial competition, but in locale (the Bohemian Grove, Bilderberg, Ditchley, Davos) or supposedly "rogue" agencies, with the CIA still at the head of the list. The 9/11 "conspiracy", or "inside job", is the Summa of all this foolishness.

One trips over a fundamental idiocy of the 9/11 conspiracists in the first paragraph of the opening page of the book by one of their high priests, David Ray Griffin, The New Pearl Harbor. "In many respects," Griffin writes, "the strongest evidence provided by critics of the official account involves the events of 9/11 itself In light of standard procedures for dealing with hijacked airplanes not one of these planes should have reached its target, let alone all three of them."

The operative word here is "should". A central characteristic of the conspiracists is that they have a devout, albeit preposterous belief in American efficiency. Many of them start with the racist premise--frequently voiced in as many words in their writings -- that "Arabs in caves" weren't capable of the mission. They believe that military systems should work they way Pentagon press flacks and aerospace salesmen say they should work. They believe that at 8.14 am, when AA flight 11 switched off its radio and transponder, an FAA flight controller should have called the National Military Command center and NORAD. They believe, citing reverently (this is high priest Griffin) "the US Air Force's own website," that an F-15 could have intercepted AA flight 11 "by 8.24, and certainly no later than 8.30."

They appear to have read no military history, which is too bad because if they did they'd know that minutely planned operations--let alone by-the-book responses to an unprecedented emergency -- screw up with monotonous regularity, by reason of stupidity, cowardice, venality and all the other failings, not excepting sudden changes in the weather.

History is generous with such examples. According to the minutely prepared plans of the Strategic Air Command, an impending Soviet attack would have prompted the missile siloes in North Dakota to open, and the ICBMs to arc towards Moscow and kindred targets. The four test launches actually attempted all failed, whereupon the SAC gave up testing. Was it badly designed equipment, human incompetence, defense contractor venality or conspiracy?

Did the April 24, 1980 effort to rescue the hostages in the US embassy in Teheran fail because a sandstorm disabled three of the eight helicopters, or because the helicopters were poorly made, or because of agents of William Casey and the Republican National Committee poured sugar into their gas tanks in yet another conspiracy?

Have the US military's varying attempts to explain why F-15s didn't intercept and shoot down the hijacked planes stemmed from absolutely predictable attempts to cover up the usual screw-ups, or because of conspiracy? Is Mr Cohen in his little store at the end of the block hiking his prices because he wants to make a buck, or because his rent just went up or because the Jews want to take over the world? Bebel said anti-Semitism is the socialism of the fools. These days the 9/11 conspiracy fever threatens to be the dominant politics of the left.

It's awful. My in-box overflows each day with fresh "proofs" of how the WTC buildings were actually demolished, often accompanied by harsh insults identifying me as a "gate-keeper" preventing the truth from getting out. I meet people who start quietly, asking me "what I think about 9/11". What they are actually trying to find out is whether I'm part of the coven. I imagine it was like being a Stoic in the second century A.D. going for a stroll in the Forum and meeting some fellow asking, with seeming casualness, whether it's possible to feed 5,000 people on five loaves of bread and a couple of fish.

Indeed, at my school in the 1950s the vicar used to urge on us Frank Morison's book, Who Moved The Stone? It sought to demonstrate, with exhaustive citation from the Gospels, that since on these accounts no human had moved the stone from in front of Joseph of Arimathea's tomb, it must beyond the shadow of a doubt have been an angel who rolled it aside and let Jesus out, so he could astonish the mourners and then Ascend. Of course Morison didn't admit into his argument the possibility that angels don't exist, or that the gospel writers were making it up.
It's the same pattern with the 9/11 conspiracists, who proffer what they demurely call "disturbing questions", though they disdain all answers but their own. They seize on coincidences and force them into sequences they deem to be logical and significant. Like mad Inquisitors, they pounce on imagined clues in documents and photos, torturing the data ­- as the old joke goes about economists -- till the data confess. Their treatment of eyewitness testimony and forensic evidence is whimsical. Apparent anomalies that seem to nourish their theories are brandished excitedly; testimony that undermines their theories--like witnesses of a large plane hitting the Pentagon -- is contemptuously brushed aside.

There are some photos of the impact of the "object" -- i.e. the Boeing 757, flight 77 -- that seem to show the sort of hole a missile might make. Ergo, 757 didn't hit the Pentagon. It WAS a missile. It wasn't smoke in some photographs obscuring a larger rupture in the fortified Pentagon wall.
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On this last matter, Chuck Spinney, now retired after years of brilliant government service exposing the Pentagon's budgetary outrages, tells me that "there ARE pictures taken of the 757 plane hitting Pentagon -- they were taken by the surveillance cameras at Pentagon's heliport, which was right next to impact point. I have seen themboth stills and moving pictures. I just missed seeing it personally, but the driver of the van I just got out of in South Parking saw it so closely that he could see the terrified faces of passengers in windows. I knew two people who were on the plane. One was ID'd by dental remains found in the Pentagon."

This won't faze the conspiracists. They're immune to any reality check. Spinney worked for the government They switched the dental records The Boeing 757 was flown to Nebraska for a rendez-vous with President Bush, who shot the passengers, burned the bodies on the tarmac and gave Spinney's friend's teeth to Dick Cheney to drop through a hole in his trousers amid the debris in the Pentagon.

In fact hundreds of people saw the plane -- people who know the difference between a plane and a cruise missile. The wreckage of the plane was hauled out from the site. Why does the obvious have to be proved? Would those who were wounded or who lost friends and colleagues that day would assist in the cover up of a missile strike? Why risk using a missile, when you had a plane in the air and ­- to take the bizarre construct of the conspiracists -- had successfully crashed (by remote control!) two into much more difficult targets--the Trade Towers?

How difficult is it to learn how to fly the jetliners if you didn't have to land them on a runway? The short answer from commercial pilots is: not very difficult. In fact, you can learn about all you need to know from spending a few weeks in front of the Flight Simulator computer program.

What do we make of Osama taking credit for the attacks? That he's still on the CIA payroll? And so it goes, on and on into the murk. But to what end? To prove that Bush and Cheney are capable of almost anything? Actually, what Bush and Cheney Bush haven't proved is the slightest degree of competence to pull anything like this off. They couldn't even manufacture weapons of mass destruction after US troops had invaded Iraq, and when any box labeled "WMD" would have been happily photographed by the embedded U.S. press as conclusive testimony.

At least what these recent elections may help to do is remind the left that Bush and Cheney are not that much different from the politicians and overlords of U.S. foreign policy who preceeded them or who will follow them. There was already a bi-partisan consensus about Israel, Iraq, et al.

Ultimately, the 9/11 conspiracists want us to believe that the Bush/Cheney gang is a new breed of evil. This might be the most dangerous deception of all, for it fosters the fantasy that a new adminstration, a Hillary or Gore administration, would pursue more humane policies

The WTC didn't fall down because they were badly built as a consequence of corruption, incompetence, regulatory evasions by the Port Authority, and because they were struck by huge planes loaded with jet fuel. No, shout the conspiracists, they "pancaked" because Dick Cheney's agents--scores of them--methodically planted demolition charges in the preceding days. It was a conspiracy of thousands, all of whom--party to mass murder--have held their tongues ever since.

Michael Neumann, a philosopher, and CounterPunch contributor, at the University of Trent, in Ontario, remarked in a note to me:
"I think the problem of conspiracy nuttery has got worse, and is part of a general trend. There really were serious questions about the Kennedy assassination, an unusual number of them, and it wasn't too crazy to come to the wrong conclusion. There wasn't a single serious question about 9-11. But this is the age of angels, creationism, corpses all over Kosovo, Arabs suspiciously speaking Arabic, Satanic child abuse, nucular Eyraquees, and channeling. The main engine of the 9-11 conspiracy cult is nothing political; it's the death of any conception of evidence.

"This probably comes from the decline of Western power. Deep down, almost everyone, across the political spectrum, is locked in a bigotry which can only attribute that decline to some irrational or supernatural power. The result is the ascendency of magic over common sense, let alone reason."

Anyone familiar with criminal, particularly death penalty defense--I had such an opportunity for a number of years--will know that there are always anomalies the prosecution cannot account for and that the defense teams can exploit, in hopes of swaying a jury either in the guilt or penalty phase of a trial. Time and again I would see the defense team spend days and weeks, even months, back-checking on a possibly vulnerable link in the evidentiary chain that could be attacked, at least to the all-important level of creating "reasonable doubt" in the mind of a juror. Expert witnesses would be imported at great expense ­- unlike states such as Texas, the justice system of California is generous in the provision of money for death penalty defense -- to challenge the prosecution's forensic evidence. Such challenges weren't hard to mount. Contrary to prosecutorial claims, there is far less intrinsic certainty in forensic evaluation than is commonly supposed, as regards fingerprints, landing marks on bullets and so forth.

But minute focus of a death penalty defense team on one such weak link often leads to a distorted view of the whole case. I remember more than one case where, after weeks of interviewing witnesses at one particular crime scene, the defense's investigator had collected enough witness reports to mount a decent attack on this aspect of the prosecution's overall case. At least this is what I thought, hearing the daily bulletins of the investigator. But whenthe camera pulled back, so to speak, and I saw the prosecution's whole case--chain of evidence, cumulative witness statements, accused's own movements and subsequent statements--it became clear enough to me and, in that case to the juries , that the accused were incontestably guilty. But even then, such cases had a vigorous afterlife, with the defense trying to muster up grounds for an appeal, on the basis of testimony and evidence withheld by the prosecution, faulty rulings by the judge, a prejudiced jury member and so on. A seemingly "cut and dried case" is very rarely beyond challenge, even though in essence it actually may well be just that, "cut and dried".

Anyone who ever looked at the JFK assassination will know that there are endless anomalies and loose ends. Eyewitness testimony is conflicting, forensic evidence possibly misconstrued, mishandled or just missing. But in my view, the Warren Commission, as confirmed in almost all essentials by the House Committee on Assassinations in the late 1970s, had it right and Oswald fired the fatal shots from the Schoolbook Depository. The evidentiary chain for his guilt is persuasive, and the cumulative scenarios of the conspiracists entirely unconvincing. But of course--as the years roll by, and even though no death bed confession has ever buttressed those vast, CIA-related scenarios -- the conspiracists keep on toiling away, their obsessions as unflagging as ever.

Of course there are conspiracies. I think there is strong evidence that FDR did have knowledge that a Japanese naval force in the north Pacific was going to launch an attack on Pearl Harbor. It's quite possible Roosevelt thought it would be a relatively mild assault and thought it would be the final green light to get the US into the war.

Indeed it's very probable that the FBI or US military intelligence, even the CIA, had penetrated the Al Qaeda team planning the 9/11 attacks; that intelligence reports--some are already known--piled up in various Washington bureaucracies pointing to the impending onslaught and even the manner in which it might be carried out.

The history of intelligence operations is profuse with example of successful intelligence collection, but also fatal slowness to act on the intelligence, along with eagerness not to compromise the security and future usefulness of the informant, who has to prove his own credentials by even pressing for prompt action by the plotters. Sometime an undercover agent will actually propose an action, either to deflect efforts away from some graver threat, or to put the plotters in a position where they can be caught red-handed. In their penetrations of environmental groups the FBI certainly did this.

Long before the 1973 Yom Kippur war, a CIA analyst noted Egyptian orders from a German engineering firm, and deduced from the type and size of equipment thus ordered that Egypt was planning an attack across the Suez canal. Why else would the Egyptians suddenly be ordering bridging materials. From the amounts being purchased and shipped he worked out the probable size of the Egyptian force and the likely time window for the attack. His superiors at the CIA sat on the report. When the Egyptian army finally attacked on October 6, 1973 the CIA high command ordered up the long-buried report, dusted it off and sent it over to the White House, marked "current intelligence". Was there a "conspiracy" by the CIA high command to allow Israel to be taken by surprise? I doubt it. Bureaucratic inertia and caution prevailed, until the moment came for decisive "cover your ***" activities.

The conspiracists make dizzying "deductive" leaps. There is a one particularly vigorous coven which has established to its own satisfaction that the original NASA moon landing was faked, and never took place. This "conspiracy" would have required the complicity of thousands of people , all of whom have kept their mouths shut. The proponents of the "fake moon landing" plot tend to overlap with the JFK and 9/11 crowds.

The "conspiracy" is always open-ended as to the number of conspirators, widening steadily to include all the people involved in the execution and cover-up of the demolition of the Towers and the onslaught on the Pentagon, from the teams acquiring the explosives and the missile, inserting the explosives in the relevant floors of three vast buildings, (moving day after day among the unsuspecting office workers), then on 9/11 activating the detonators. Subsequently the conspiracy includes the disposers of the steel and rubble, the waste recyclers in Staten Island and perhaps even the Chinese who took the salvaged incriminating metal for use in the Three Gorges dam, where it will submerged in water and concrete for ever. Tens of thousands of people, all silent as the tomb to this day.

The conspiracists simultaneously credit their targets--the Bush-Cheney "conspirators" -- with superhuman ingenuity and grotesque carelessness. In Webster Griffin Tarpley's book 9/11 Synthetic Terror Made in USA he writes that "in an interview with Parade magazine, Defense Secretary Rumsfeld also referred to the object which hit the Pentagon as a 'missile'. Was this a Freudian slip by the loquacious defense chief?"

The physicist and engineer Manuel Garcia Jr (whose explications furnish the bulk of our 9/11 file) reminds us that if the evidence allows for several explanations to a given problem then the hypothesis with the fewest assumptions is most probably correct. This principle is called Occam's Razor, named after the 14th-century English logician and Franciscan friar William of Occam.

There is not the slightest need to postulate pre-placed explosive charges to explain why the towers collapsed at near free fall speeds. Engineer Pierre Sprey--who designed the F-16 and A-10 -- points out a few practical aspects of explosive demolitions that make the explosive charge hypothesis improbable to the point of absurdity:

"1. Any demolitions expert concocting a plan to hit a tall building with an airplane and then use pre-placed explosives to UNDETECTABLY ensure the collapse of the building would never place the explosives 20, 30 and 60 floors below the impact point. Obviously, he would put the explosives on one or more floors as close as possible to the planned impact level.

"2. It is inconceivable that our demolitions expert would time his surreptitious explosions to occur HOURS after the aircraft impact. He couldn't possibly be absolutely certain that the impact fires would even last an hour. Quite the opposite: to mask the booster explosions, he'd time them to follow right on the heels of the impact.

"3. To ensure collapse of a major building requires very sizable demolition charges, charges that are large enough to do a lot more than emit the "puffs of smoke" cited as evidence for the explosives hypothesis. I've seen both live and filmed explosive building demolitions. Each explosion is accompanied by a very visible shower of heavy rubble and a dense cloud of smoke and dust. Just that fact alone makes the explosives hypothesis untenable; no demolitions expert in the world would be willing to promise his client that he could bring down a tall building with explosions guaranteed to be indistinguishable from the effects of an aircraft impact."

Herman Soifer, a retired structural engineer, summarize the collapse of Buildings 1 and 2 succinctly, in a letter to me, remarking that since he had followed the plans and engineering of the Towers during construction he was able to explain the collapses to his wife a few hours after the buildings went down.

"The towers were basically tubes, essentially hollow. Tubes can be very efficient structures, strong and economical. The Trade Center tubes effectively resisted vertical loads, wind loads and vibrations and could probably have done very well against earthquakes. However, the relatively thin skin of the hollow tube must be braced at intervals to prevent local buckling of the skin under various possible loads, otherwise the tube itself can go out of shape and lose its strength.

"For their interior bracing, the thin-walled tubes of the Trade Center towers depended primarily on the interior floors being tied to the outer wall shells. These floor beam structures were basically open web joists, adequate for the floor loads normally to be expected. These joist ends rested on steel angle clips attached to the outer walls.

"As the floors at the level of airplane impact caught fire, the open web joists, which could not be expected to resist such fires, softened under the heat, sagged and pulled away from their attachments to the walls. Their weight and the loads they were carrying, caused them to drop onto the next lower floor, which was then carrying double loads also becoming exposed to the heat. Then that floor collapsed, and so it went. But as the floors dropped, they no longer served as bracing for the thin-walled main tubes.

"This loss of bracing permitted the walls to buckle outward in successive sections and thus the house of cards effect.

"There was no other major bracing as would be encountered in a more conventional type of structure, or as might have been introduced in the design if one feared the potential loss of the floors. There were no stiff horizontal trusses in the perimeter to act as bracing ribs every few floors. There was no system of vertical trusses to provide any integrity, not was there anything that could be considered a frame or "skeleton" of columns and attached girders to keep the tube intact."

In our 9/11 file Manuel Garcia devastates with conspiracists' theories with patient explanations as to why their schemas flout scientific laws and the observed facts of the disasters of that day.

The conspiracists' last card is the collapse of WTC building number 7 some hours after the morning attacks. But here again, as with the other two buildings, the explanations offered by US government agencies (preeminently the National Institute of Standards and Technology and, for Building 7, FEMA) are more than adequate, as Manuel Garcia points out. The blast of hot debris from WTC 1 kindled fires in WTC 7 and caused an emergency power system to feed the burning to the point of building collapse.

One of the building's major bridging supports was heated to the point of exhaustion by the burning of an abundant store of hydrocarbon (diesel) fuel, pumped from the sub-basement by the back-up system and spraying through a torn pipe into the fire next to two of the building's three major structural truss. The types of steel used in the WTC Towers (plain carbon, and vanadium) lose steel lose half their strength when heated to about 570 C , and even more as temperatures rise, as they did in WTC 1 and 2, to 1100 C. In building 7, Garcia calculates that the diesel fuel spraying at a rate of 75 gallons a minute ultimately released energy equivalent to that of an explosion of 367 tons of TNT.

What is the goal of the 9/11 conspiracists? They ask questions, yes, but they never answer them. They never put forward an overall scenario of the alleged conspiracy. They say that's not up to them. So who is it up to? Who do they expect to answer their questions? When answers are put forward, they are dismissed as fabrications or they simply rebound with another question.

Of course the buildings didn't suddenly fall at a speed inexplicable in terms of physics unless caused by carefully pre-placed explosives, detonated by the ruthless Bush-Cheney operatives. High grade steel can bend disastrously under extreme heat. As discussed in Wayne Barrett and Dan Collin's excellent book Grand Illusion, about Rudy Giuliani and 9/11, helicopter pilots radioed warnings nine minutes before the final collapse that the South Tower might well go down and, repeatedly, as much as 25 minutes before the North Tower's fall.

What Barrett and Collins brilliantly show are the actual corrupt conspiracies on Giuliani's watch: the favoritism to Motorola which saddled the firemen with radios that didn't work; the ability of the Port Authority to skimp on fire protection, the mayor's catastrophic failure in the years before 9/11/2001 to organize an effective unified emergency command that would have meant that cops and firemen could have communicated; that many firemen wouldn't have unnecessarily entered the Towers; that people in the Towers wouldn't have been told by 911 emergency operators to stay in place; and that firemen could have heard the helicopter warnings and the final Mayday messages that prompted most of the NYPD men to flee the Towers.
That's the real political world, in which Giuliani and others have never been held accountable. The conspiracists disdain the real world because they have promoted Bush, Cheney and the Neo-Cons to an elevated status as the Arch Demons of American history, instead of being just one more team running the American empire, a team of more than usual stupidity and incompetence (characteristics I personally favor in imperial leaders). The conspiracists have combined to produce a huge distraction, just as Danny Sheehan did with his Complaint, that mesmerized and distracted much of the Nicaraguan Solidarity Movement in the 1980s, and which finally collapsed in a Florida courtroom almost as quickly as the Towers.

There are plenty of real conspiracies in America. Why make up fake ones? Every few years, property czars and city government in New York conspire to withhold fire company responses, so that enough of a neighborhood burns down for the poor to quit and for profitable gentrification to ensue. That's a conspiracy to commit ethnic cleansing, also murder.

It's happening today in Brooklyn, even as similar ethnic cleansing and gentrification is scheduled in San Francisco. Bayview Hunters Point is the last large black community in the Bay Area, sitting on beautiful bay front property. So now it's the time to move the black folks out. As Willie Ratcliff, publisher of the Bay View newspaper writes, "If the big developers and their puppets, the mayor [Democrat Gavin Newsom] and his minions win this war, they'll have made what may be the largest urban renewal land grab in the nation's history: some 2,200 acres of San Francisco, the city with the highest priced land on earth."

That's an actual conspiracy, even as many in the Bay Area left meander through the blind alleys of 9/11 conspiratorialism.

Machiavelli points out that every conspirator you add to the plot has less chance of preserving secrecy than the previous one. The 9/11 group in fact did tell people about their plans in various ways but the prevailing belief that Arabs couldn't do it prevented any of the revelations from being taken seriously. The view that a bunch of Arabs with box cutters couldn't do it was precisely the cover they needed.

The conspiracy virus is an old strand:

The Russians couldn't possibly build an A bomb without Commie traitors. The Russians are too dumb. Hitler couldn't have been defeated by the Red Army marching across Eastern Europe and half Germany. Traitors let it happen. JFK couldn't have been shot by Oswald -- it had to be the CIA. RFK couldn't have been shot by Sirhan--it had to be the CIA. There are no end to examples seeking to prove that Russians, Arabs, Viet Cong, Japanese, etc etc couldn't possibly match the brilliance and cunning of secret cabals of white Christians. It's all pathetic but it does save the trouble of reading and thinking.

Yet some discover a silver lining in the 9/11 conspiracism. A politically sophisticated leftist in Washington, DC, wrote to me recently, agreeing with my ridiculing of the "inside job" scenarios, but adding, "To me the most interesting thing (in the US) is how many people are willing to believe that Bush either masterminded it [the 9/11 attacks] or knew in advance and let it happen. If that number or anything close to that is true, that's a huge base of people that are more than deeply cynical about their elected officials. That would be the real news story that the media is missing, and it's a big one."

"I'm not sure I see the silver lining about cynicism re government," I answered. "People used to say the same thing about the JFK conspiracy buffs and disbelief in the Warren Commission. Actually, it seems to demobilize people from useful political activity. If the alleged perpetrators are so efficiently devilish in their plots, all resistance is futile. As Michael Snedeker, a lawyer who spends much of his professional life trying to save accused murderers from the death penalty, wrote to me about the 9/11 conspiracists:

"I completely agree with your take on the 9/11 conspiracy theorists. Of course, it would be an outrage if such monstrous, complicated schemes were hatched and carried out so smoothly, but it would be somehow worse if no one at all was orchestrating the whole piece. There is definitely a theological motor driving that train--a need for Order and Design. The power of forces like Ineptitude, Sloth, Distraction & Resentment are routinely overlooked. We all know them in our own lives, but somehow, it is assumed by analysts of all stripes that office-holders and Boards of Directors, etc., are immune. Ha! At the risk of going all Freudian here, I think such theories are another reflection of the deep desire for an all-knowing Father, & the terror of being one of a band of brothers and sisters, with no one other than ourselves to guide us."

As for the theological motor, note that Griffin is a theologian, and his latest book put out by a publisher connected to the Presbyterian church--a fact which does not sit well with many Presbyterians, though 9/11 conspiracists have hailed the association as evidence that protestant America is rallying to their standard. Maybe the Heavenly Father decided to destroy Babel and start again. As Garcia wryly remarks at the end of second essay, on the thermodynamics of 9/11: "In the enormity of each rubble pile, with its massive quantity of stored heat, many effects were possible in small quantities, given time to incubate. It is even possible that in some little puddle buried deep in the rubble, warmed for months in an oven-like enclosure of concrete rocks, bathed in an atmosphere of methane, carbon monoxide, carbon dioxide, and perhaps a touch of oxygen, that DNA was formed."

9/11 conspiracism stems from despair and political infantilism. There's no worthwhile energy to transfer from such kookery. It's like saying some lunatic shouting to himself on a street corner has the capacity to be a great orator. As Garcia suggests, the nearest thing to it all is the Flying Saucer craze of the 1950s, born of fears of atomic war. It's a Jungian thing.

Richard Aldrich's book on British intelligence, The Hidden Hand (2002), describes how a report for the Pentagon on declassification recommended that "interesting declassified material" such as information about the JFK assassination "could be released and even posted on the Internet, as a 'diversion,'" and used to "reduce the unrestrained public appetite for 'secrets' by providing good faith distraction material". Aldrich adds, "If investigative journalists and contemporary historians were absorbed with the vexatious, but rather tired, debates over the grassy knoll, they would not be busy probing into areas where they were unwelcome."

By the same token, I'm sure that the Bush gang, and all the conspirators of capital, are delighted at the obsessions of the 9/11 conspiracists. It's a distraction from the 1,001 real plots of capitalism that demand exposure and political challenge.

"The tendency to occultism is a symptom of regression in consciousness", Adorno wrote in Minima Moralia. . "The veiled tendency of society towards disaster lulls its victims in a false revelation, with a hallucinated phenomenon. In vain they hope in its fragmented blatancy to look their total doom in the eye and withstand it The offal of the phenomenal world becomes, to sick consciousness, the mundus intelligibilis."

Footnote: I should add that one particular conspiracist, seeing that Roosevelt's grandson Ford--a schoolteacher in Los Angeles--was for a while, some years ago, on the board of CounterPunch's parent non-profit, the Institute for the Advancement of Journalistic Clarity -- wrote an enormous onslaught on CounterPunch a while ago, "proving" to his own satisfaction that CounterPunch was a pawn of the Democratic Party, the CIA and kindred darker forces. I suppose the fact that CounterPunch attacked the Democratic Party and the CIA on a weekly basis was just one more example of our cunning in deflecting suspicion away from our true sponsors. The fact that from time to time that we also quite regularly attacked FDR--and posited his foreknowledge of Pearl Harbor--should again be taken as evidence of our stratagems in trying to obscure Ford's supervisory role in our affairs. In fact we'd put Ford on the board in the hopes (vain, as they turned out to be) that he would persuade film stars to give CounterPunch money.
 
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We See Conspiracies That Don't Exist
The Physics of 9/11

By MANUEL GARCIA, Jr.

Five years after the events of September 11, 2001, conspiracy theories abound as an anxious public seeks to find a comprehensible story for that day and more broadly for their socio-political world. People need reliable foundations upon which to base the many assumptions and conventions they use to carry on their lives.

Half a century ago, public anxiety about the danger of atomic energy and the terror of thermonuclear war exhibited itself in sightings of flying saucers, and a fad of monster movies. C. G. Jung wrote about flying saucer sightings as an instance of "mass psychosis": a "psychological infection" that spreads among people who lack sufficient understanding to rationalize fearsome political forces and unstable social conditions (Flying Saucers: A Modern Myth, 1958). Jung was sensitive to any indication that another "psychological epidemic" might erupt, as Nazism did, among a population whose government possessed awesome military power. Mass psychosis is a myth held in common, which releases the population from the "normal" restraints of rationality and international social conventions, so they can pursue their mythical vision. The ignorance -- and the fears that spring from it as prejudices -- of the entranced population is "projected" onto "enemies" whose destruction is sought in the irrational effort to eliminate the actual problem of psychological tensions, (1)

A more entertaining expression of popular anxiety is the monster movie. "Godzilla," "Rodan," "Them," "The Thing" and many others safely frightened viewers with stories of monsters whose introductions into human society were caused by atomic bomb testing, or were accompanied by radioactivity. For most Americansthe major source of any knowledge of physics is probably this type of motion picture.

The myths we construct to express our understanding of the realities we are immersed in are limited by the range of our knowledge. When the myths are meant to cover over fears about forces beyond our control, they can be conspiracy theories. Consider these pairings of fears and rationalizations:

fear of political power --> conspiracy theories;

metaphysical fear (fear of death) --> religion, a theological conspiracy ;

fear of personal inadequacy-->racism,

fear of strange cultures--> ultra-nationalism

Certainly, so long as there are more than two people on Earth, conspiracies will occur. But too often we invoke a conspiracy in constructing our story of the world because we lack specific information about the sciences, economics, history and other relevant fields of specialized knowledge. Experience has shown that if the evidence allows for several explanations to a given problem then the hypothesis with the fewest assumptions is most probably correct. This principle is called Occam's Razor and is attributed to the 14th-century English logician and Franciscan friar William of Occam (c. 1295­1349) (2).

The events of September 11, 2001, were unsettling for many Americans because their existing myths were shattered; these myths had provided comfort and lain undisturbed in consciousness since indoctrination had lodged them there. The increasing power of communications technology --global telephone networks, the Internet --and the accelerating disregard of subtlety by the elite in its management of public perceptions about government policies has eroded the myths --or illusions --of many Americans. So, trust in government has been broken, fear of its power is vivid, and understanding of the physical mechanisms of Nature is limited. This psychology will naturally sprout conspiracy theories about 9/11.

The aim of this article is to supply some understanding of physics as it relates to several of the features of the 9/11 events, so that readers can expand their range of rationality and hence their political maturity.

The reports on the investigations of the collapse of the World Trade Center buildings conducted by the National Institute of Standards and Technology (originally the National Bureau of Standards) are to be found at a special NIST website ("NIST & The World Trade Center, Final Report (Sept. 2005),"

This multi-volume Final Report, issued in September 2005, is the "official word." There is a vast amount of dry text, much data, descriptive summaries of detailed calculations of the impact ruptures, fires and heating, subsequent deformation, load-shifting, buckling and ultimate failure of the buildings. NIST addressed the sequence of events and shifting of loads leading up to the failure that allowed the upper blocks to drop; it did not proceed to a detailed simulation of the collapses to the ground. NIST justified this on the grounds that there was sufficient energy in the descending blocks to crush the lower structures, once failures had occurred.

The controlled demolition hypothesis for the collapse of the World Trade Center buildings is described at length in a Wikipedia article ("Controlled demolition hypothesis for the collapse of the World Trade Center,"

The popularity of 9/11 conspiracy theories (also outlined in a useful Wikipedia entry) has prompted NIST to present a very nice webpage addressing the usual questions of the conspiracy viewpoint, and providing clear descriptions in non-technical English of the physics and engineering explanations embodied in the NIST WTC Towers Final Report .


Summary of NIST Findings

The World Trade Center Towers (WTC 1, WTC 2) were tall square buildings with supporting columns grouped along the vertical axis (center) and closely spaced along the perimeter (building faces). A "hat truss," at the top of each building, tied the outer walls to the central columns; and this truss had a height equal to that of five stories.

A hijacked airliner was crashed into each building about 10 or 20 stories down from the top. The columns along one face of the building were sheared for a height of several floors, as were many of the columns at the core. The exploding fuel from the airliner ignited fires throughout the levels within the impact zone, as well as dropping fire down the stairwells and elevator shafts at the building's core, and billowing up to higher levels. The shocks of impact and detonation loosened the "fire protection" thermal insulation on steel beams in the impact zone.

The damaged core columns in the impact zone could no longer hold up all the weight they were meant to carry. The core columns in the upper block now found it necessary to partially hang from the hat truss. The hat truss pressed down much more forcefully on the perimeter columns, transferring the load of the hanging weight. The added compression of the perimeter columns could only be distributed to the three undamaged faces, and because of the irregularity of the damage one face assumed a much higher load than the other two.

The fuel fire burned up to 1,100 degrees C (2,000 degrees F) for perhaps 10 minutes. It ignited the many plastic furnishing (carpets, curtains, furniture, equipment cases, clothing, fixtures, office ceilings and partitions), paper items (paper supplies, books, pressed wood), and some structural elements (gypsum wall boards, plastic plumbing), which then continued the fire. The exposed steel beams in the impact zone heated to between 700 C to 1,000 C. Steel at 700 C has 50 per cent to 70 per cent of its strength at habitable temperatures; and steel at 1,000 C has between 10 per cent to 30 per cent.

The floors in the impact zone sagged because of broken joints to central columns, heat causing their metal framing to soften, weaken and expand; also because of the weight of debris fallen from above . The sagging floors twisted their joints to the perimeter columns (on the three intact faces); the length of column above a floor joint being twisted inward. For one face of the building, the combined stress of the original weight above it, the added compression from the hat truss, and the torque from the sagging floors were too much. Its perimeter beams were bent inward to the point of failure, and they buckled.

The NIST investigation was an extremely detailed analysis by 200 engineers and building professionals, describing the conditions of the buildings from the instant an airplane collided to the moment a collapse began. The next section of this CounterPunch report carries the story downward from the point where NIST leaves off. NIST concentrated its resources on the greatest uncertainty: what initiated the collapse? It was understood that once an upper block of the building was in motion the structure below would be unable to counter the dynamic forces, and collapse would proceed to the ground.

Physics Problem Number 1 -- Free Fall of the WTC Towers

"How could the WTC towers collapse in only 11 seconds (WTC 1) and 9 seconds (WTC 2), speeds that approximate that of a ball dropped from a similar height in vacuum (with no air resistance)?" (NIST FAQ #6)

The suspicion behind this question is that the Towers were weakened by surreptitious, controlled demolitions. In this view, the structure below the impact zone (where airplanes collided, exploded, and fires burned) "should have" provided resistance to the descent of the block above the impact zone, slowing or even stopping the collapse.

The NIST response is that the lower structure was only designed to hold up the weight above any given floor statically, not dynamically. The force imparted by the collision of the upper block was beyond the limits of the lower structure to resist. The lower structure was essentially crumbled by a "hammer" of descending material, and the mass of this hammer increased during the course of the collapse.

Let's explore further.

¦ Problem 1, Force Balance

Once the framing in the impact zone has failed, the upper block is accelerated by gravity until it crashes into the lower structure below the impact zone. Labeling the mass of the upper block m, and its speed v, the block would have a momentum m*v and an energy of (1/2)*m*v^2. Its weight would be m*g, where g is the constant of gravitational acceleration (9.81 meters/second^2).

The balance of forces on the upper block as it impacts the lower structure is presented here as the impulse momentum form of Newton's 2nd Law:

The time rate of change of momentum = The sum of the forces,

[m*v(final) - m*v(initial)]/dt = F - m*g.

Here, positive direction, velocity and force are taken to be vertically upward; dt is a label for "delta t", a very brief time interval during which the impact occurs and the momentum changes from m*v(initial) to m*v(final); and F is the force of resistance by the lower structure. If A is the net horizontal cross-sectional area of the load-bearing columns of the lower structure, then F/A is the average compressive stress across that area.

This type of force balance is applied to the impact at each floor, sequentially, by redefining m as the mass above it, v(initial) as the outcome of the alternating floor impacts and free falls during prior compaction, and v(final) as the outcome of the latest impact.

We can regroup the terms of the force balance as follows:

F = m*g + m*[v(final) - v(initial)]/dt,

F = m*g*[1 + {v(final) - v(initial)}/(g*dt)],

F/(m*g) = 1 + {v(final) - v(initial)}/(g*dt).

Before each building was perturbed, the upper block did not have any motion, v(initial) = v(final) = 0, and the magnitude of the upward-directed, resisting force of any part of the structure was equal to the weight of material above it; F/(m*g) = 1.

When an upper block drops through an impact zone that has lost structural strength, and crashes into the rigid lower structure, it imparts a dynamic force in addition to its weight. The dynamic force is the second term in the last expression for F. The total force, F, acts during the time interval dt during which the momentum of the upper block is reduced (in magnitude) from m*v(initial) to m*v(final). Clearly, the lower structure will crumble when F is greater than the maximum force it can support, or when F/A is greater than the maximum stress it can withstand.

¦ Problem 1, Numerical Example of Progressive Collapse

Free fall without air resistance from a height H takes time T, given by

T = square root [(2*H)/g].

At any time 0 < t < T during the free fall, the velocity is given by

v(t) = -g*t, (negative sign for downward direction),

and position is given by

h(t) = H - (1/2)*g*t^2.

So, for H = 440 m (=1443 feet) the free fall time is T = 9.5 s, and the velocity slamming into the ground is -92.9 m/s = -208 mph.

What actually happened in the buildings? We consider a suggestive numerical example.

With the onset of failure, the upper block drops through a space of L = 3 meters, taken to be the distance between floors. Starting from rest at time t = 0, the block reaches a velocity of v = -7.7 m/s at t = 0.78 s. The descending block makes contact with the topmost stationary floor of the lower structure.

We will assume these floor structures to be dL = 1 meter thick (1 meter = 3.28 feet). Each floor structure is a framework of steel below and within a layer of concrete. The floors spanned a distance of between 10 m and 20 m between the outer square perimeter (63.4 m a side) and the core support along the axis of the building, which housed elevator shafts, stairwells and support columns, within a rectangular area of [42 m x 27 m].

Impact is a very brief process whose duration is dt = 1/100 s. During the impact, energy ripples through the floor structure as elastic waves in the steel and concrete; the velocity of these stress waves is V(steel) = 1900 m/s and V(concrete) = 930 m/s; the wave speed is a property of the material (P-waves). The waves traverse the thickness of the floor structure in a time dL/V = 5/10,000 s for steel and 1/1000 s for concrete, so they can bounce between 10 to 20 times across the 1 m thickness; and they can run along the span of the floor within 0.005 to 0.01 s.

The waves alert the volume of the floor structure to the imposition of a new load, and infuse that volume with much higher stress. The floor structure is deflected downward a distance d = -0.077 meters (3 inches) during impact. In becoming stressed, the floor structure absorbs some of the energy of the descending block, slowing it by dv = 0.5 m/s (in this example). Within dt = 1/100 s, the floor structure has transmitted the force of the new load to its joints with the building's core and periphery.

Recalling the last form of the force balance, and inserting the numbers from this example, we find the magnitude of the total reaction force to be

F/(m*g) = 1 + dv/(g*dt) = 1 + 0.5/(9.81*0.01) = 6.1,

a load of six times the weight of the upper block.

I continued this particular calculation, floor by floor, as a sequence starting from rest: free fall for 3 m, impact delays transit for 0.01 s and decreases descent velocity by 0.5 m/s, free fall for 3 m, transit delay and velocity decrement as before, and so on. The block reaches the ground in 10 s with a total of 87 floor impacts. The collapse of 344 m (1128 feet) accelerates from -7.2 m/s (-16 mph) after the initial impact, to -46 m/s (-104 mph) at the ground.

Now, a little bit more about waves.

&#166; Problem 1, Wave Trains and Stress Concentration

Elastic waves are launched from the collapse front (the leading edge of descending material, like "weather front") at the moment of first impact. Within 0.01 s, a stress wave has traveled through the metal framework to five levels below the collapse front, a distance of 20 m. These lower levels experience a rapid --dare I say explosive? --increase in the stress within their frames. Bolts and rivets may be sheared, and joints ruptured by the resulting impulsive forces.

For example, assume a carbon steel (HR 0.45C) bolt or rivet of 1 inch diameter is used to support a force of 8,000 kilograms, equivalent to a stress of 22,500 pounds-per-square-inch (psi). This stress is only one quarter of that material's tensile strength of 90,000 psi; an apparently conservative design. However, an unexpected increase in load by a factor of five, to a total of 48,000 kg, or 135,000 psi, would probably rupture the joint.

The stress wave from the initial impact races down the lower structure, arriving at ground level in 0.18 s (we continue with the numerical example). During that time, the collapse front has descended another 1.3 m. The stress wave is like a messenger telling the material it passes to "move down and compress" in response to the advancing collapse front. On reaching the ground, the wave could transmit some of its energy past the building's foundation to radiate as a seismic wave through the earth, and another portion of its energy would reflect back up (the major effect, especially if the foundation is more rigid than the building it supports). The message of the upward running wave is "compress even more, dead-end down below."

Elastic waves launched by an impulsive load on a structure that remains intact --like a bell being struck --will ripple back and forth, spreading out the initially concentrated stress of the strike. If the load is suddenly imposed and then remains constant, as with a book being dropped on a sturdy table, then the elastic waves die out into a fairly uniform distribution of stress throughout the volume. If the load is a short pulse, like striking a bell, then the waves will eventually die out as a fairly uniform heating of the material.

Just as there are ripples on wavelets, and wavelets on big rollers across the surface of the ocean, so will each elastic wave launched by the collapse be a jumble of waves of different size grouped together. The many individual collisions of material that make up the global impact of the upper block into a floor structure will each send off their own ripples, which all build up into a composite for the elastic wave.

A new elastic wave is launched with each impact between the collapse front and a stationary floor structure. As the collapse front accelerates, the time interval between wave launchings decreases. The building below the collapse front experiences an increasing level of stress and becomes filled with intersecting wave trains moving up and down by the time of the second impact at 1.13 s. Elastic waves that pass through each other will produce a heightened stress where they coincide, just like crossing water waves that mound noticeably.

This agitated lacework of stresses ahead of the collapse front will probably cause many fractures and break many joints prior to the arrival of the front. The sudden shifts in the volume of rooms and office spaces being compressed and twisted by the elastic wave trains can easily expel jets of air and dust out of windows, perhaps giving the impression of smoke from a gun barrel. The collapse front will push a blast of air down before it and also produce lateral jets of air from the building below it. These air streams are analogous to the water expelled sideways and into vortexes alongside a paddle pushing a canoe through still water.

All these wave effects occur in the upper block as well, from the moment of first impact. The upper block will quickly fill with elastic waves, which will rupture internal joints; the block shatters, as is vividly seen in the video recordings of the WTC collapses. The shorter length of the upper block, and its lack of firm connection (like a foundation), will contribute to the speed of its disintegration. In a very real sense the upper block was "blown up," but naturally by elastic waves rippling a destructive compression through it rather than artificially by intentional controlled demolition.

Pancaking, Buckling and Hyping (Red Herring #1)

Two days after the collapse of the World Trade Center Towers, Zdenek P. Bazant, a civil engineering professor at Northwestern University, publicized his theory of the collapse initiation. His conjectures about loosened fire insulation and heated steel losing strength survived the subsequent scrutiny by NIST. However, NIST rejected Bazant's proposed mechanism for the initiation of the collapse, referred to subsequently as the "pancake model" or "pancaking." Because of its early appearance on the scene, Bazant's model was widely circulated. Critics of NIST and the "official" story will point to the divergence of NIST's conclusions from Bazant's, four years earlier, as an indication of ignorance, confusion --or worse --complicity and cover-up on the part of the "government" people.

Bazant's pancake model is shown in Figure 1 of his report . Bazant assumed that interior columns within the impact zone would weaken from heating, buckle, and then the upper block would fall through the impact zone onto the lower structure. This impact would cause the columns in the immediate levels below ("3 to 10 seems likely") to bow, or in Bazant's words:

"This causes failure of an underlying multi-floor segment of the tower, in which the failure of the connections of the floor-carrying trusses to the columns is either accompanied or quickly followed by buckling of the core columns and overall buckling of the framed tube, with the buckles probably spanning the height of many floors, and the upper part possibly getting wedged inside an emptied lower part of the framed tube."

In other words, the upper block falls within the perimeter columns onto a lower floor, and that shock pops the floor joints around the perimeter and at the core for 3 to 10 floors below. Once in motion, this process would crush all beneath it.

NIST concludes:

"NIST's findings do not support the pancake theory of collapse[The] investigation showed conclusively that the failure of the inwardly bowed perimeter columns initiated collapse and that the occurrence of this inward bowing required the sagging floors to remain connected to the columns to pull the columns inwards. Thus, the floors did not fail progressively to cause a pancaking phenomenon."

For a shot from the hip two days after the collapse, Bazant did pretty well. But, after the NIST legion did all the necessary homework, we now have an accurate result. NIST shows pictures of the inward buckle of the perimeter wall, taken from a police helicopter. Pancaking versus NIST is a nonexistent technical argument only to be found in the imagination of some conspiracy-minded people. The technical community migrated from early hypotheses of the initiation, like pancaking, to the NIST conclusions as a consequence of doing the hard work required. And, there was always unanimity on what drove the collapse once it was initiated: excess dynamic force produced from the gravitational potential energy contained within even one level spacing. Once the top began to fall, it was going to crush the building below it, regardless.


The Absurdity of "Controlled Demolition" (Red Herring #2), by Pierre Sprey

Pierre Sprey is CounterPunch's technical reviewer of this report. His comments about the controlled demolition hypothesis are so cogent that I include them here.

Sprey:

There is not the slightest need to postulate pre-placed explosive charges to explain why the towers collapsed at near free fall speeds. Let me note a few practical aspects of explosive demolitions that make the explosive charge hypothesis improbable to the point of absurdity:

1. Any demolitions expert concocting a plan to hit a tall building with an airplane and then use pre-placed explosives to UNDETECTABLY ensure the collapse of the building would never place the explosives 20, 30 and 60 floors below the impact point. Obviously, he would put the explosives on one or more floors as close as possible to the planned impact level.

2. It is inconceivable that our demolitions expert would time his surreptitious explosions to occur HOURS after the aircraft impact. He couldn't possibly be absolutely certain that the impact fires would even last an hour. Quite the opposite: to mask the booster explosions, he'd time them to follow right on the heels of the impact.

3. To ensure collapse of a major building requires very sizable demolition charges, charges that are large enough to do a lot more than emit the "puffs of smoke" cited as evidence for the explosives hypothesis. I've seen both live and filmed explosive building demolitions. Each explosion is accompanied by a very visible shower of heavy rubble and a dense cloud of smoke and dust. Just that fact alone makes the explosives hypothesis untenable; no demolitions expert in the world would be willing to promise his client that he could bring down a tall building with explosions guaranteed to be indistinguishable from the effects of an aircraft impact.

My Conclusions

The WTC towers collapsed at speeds approaching that of free fall because:

1. The dynamic force created out of the gravitational potential energy within the space of just one level spacing was far in excess of the static force the framing was designed to support, and

2. Elastic waves launched from the collapse front quickly filled the building --both lower structure and upper block --with large dynamic stresses, which weakened and ruptured joints well in advance of that material entering the collapse front.

The towers shattered, and the pieces fell to the ground.

In part 2 of this report I address the topic of heat, a prominent feature of many conspiracy theories about the collapse of the WTC buildings. In part 3 I address the collapse of WTC 7

Manuel Garcia a native New Yorker who works as a physicist at the Lawrence Livermore National Laboratory in California with a PhD Aerospace & Mechanical Engineering, from Princeton His technical interests are generally in fluid flow and energy, specifically in gas dynamics and plasma physics; and his working experience includes measurements on nuclear bomb tests, devising mathematical models of energetic physical effects, and trying to enlarge a union of weapons scientists. He can be reached at mango@idiom.com
 
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We See Conspiracies That Don't Exist
The Thermodynamics of 9/11

By MANUEL GARCIA, Jr.

When hijacked airliners crashed into the tall Towers of the World Trade Center, in New York City, each injected a burning cloud of aviation fuel throughout the 6 levels (WTC 2) to 8 levels (WTC 1) in the impact zone. The burning fuel ignited the office furnishings: desks, chairs, shelving, carpeting, work-space partitions, wall and ceiling panels; as well as paper and plastic of various kinds.

How did these fires progress? How much heat could they produce? Was this heat enough to seriously weaken the steel framework? How did this heat affect the metal in the rubble piles in the weeks and months after the collapse? This report is motivated by these questions, and it will draw ideas from thermal physics and chemistry. My previous report on the collapses of the WTC Towers described the role of mechanical forces (1).


Summary of National Institute of Technology and Standards (NIST)

Basic facts about the WTC fires of 9/11 are abstracted by the numerical quantities tabulated here.

Table 1, Time and Energy of WTC Fires

Item WTC 1 WTC 2

impact time (a.m.) 8:46:30 9:02:59

collapse (a.m.) 10:28:22 9:58:59

time difference 1:41:52 0:56:00

impact zone levels 92-99 78-83

levels in upper block 11 27

heat rate (40 minutes) 2 GW 1 GW

total heat energy 8000 GJ 3000 GJ

Tower 1 stood for one hour and forty-two minutes after being struck between levels 92 and 99 by an airplane; the block above the impact zone had 11 levels. During the first 40 minutes of this time, fires raged with an average heat release rate of 2 GW (GW = giga-watts = 10^9 watts), and the total heat energy released during the interval between airplane impact and building collapse was 8000 GJ (GJ = giga-joules = 10^9 joules).

A joule is a unit of energy; a watt is a unit of power; and one watt equals an energy delivery rate of one joule per second.

Tower 2 stood for fifty-six minutes after being struck between levels 78 and 83, isolating an upper block of 27 levels. The fires burned at a rate near 1 GW for forty minutes, diminishing later; and a total of 3000 GJ of heat energy was released by the time of collapse.

WTC 2 received half as much thermal energy during the first 40 minutes after impact, had just over twice the upper block mass, and fell within half the time than was observed for WTC 1. It would seem that WTC 1 stood longer despite receiving more thermal energy because its upper block was less massive.

The data in Table 1 are taken from the executive summary of the fire safety investigation by NIST (2).

The NIST work combined materials and heat transfer lab experiments, full-scale tests (wouldn't you like to burn up office cubicles?), and computer simulations to arrive at the history and spatial distribution of the burning. From this, the thermal histories of all the metal supports in the impact zone were calculated (NIST is very thorough), which in turn were used as inputs to the calculations of stress history for each support. Parts of the structure that were damaged or missing because of the airplane collision were accounted for, as was the introduction of combustible mass by the airplane.

Steel loses strength with heat. For the types of steel used in the WTC Towers (plain carbon, and vanadium steels) the trend is as follows, relative to 100&#37; strength at habitable temperatures.

Table 2, Fractional Strength of Steel at Temperature

temperature, degrees C fractional strength, %

200 86

400 73

500 66

600 43

700 20

750 15

800 10

I use C for Centigrade, F for Fahrenheit, and do not use the degree symbol in this report.

The fires heated the atmosphere in the impact zone (a mixture of gases and smoke) to temperatures as high as 1100 C (2000 F). However, there was a wide variation of gas temperature with location and over time because of the migration of the fires toward new sources of fuel, a complicated and irregular interior geometry, and changes of ventilation over time (e.g., more windows breaking). Early after the impact, a floor might have some areas at habitable temperatures, and other areas as hot as the burning jet fuel, 1100 C. Later on, after the structure had absorbed heat, the gas temperature would vary over a narrower range, approximately 200 C to 700 C away from centers of active burning.

As can be seen from Table 2, steel loses half its strength when heated to about 570 C (1060 F), and nearly all once past 700 C (1300 F). Thus, the structure of the impact zone, with a temperature that varies between 200 C and 700 C near the time of collapse, will only have between 20% to 86% of its original strength at any location.

The steel frames of the WTC Towers were coated with "sprayed fire resistant materials" (SFRMs, or simply "thermal insulation"). A key finding of the NIST Investigation was that the thermal insulation coatings were applied unevenly -- even missing in spots -- during the construction of the buildings, and -- fatally -- that parts of the coatings were knocked off by the jolt of the airplane collisions.

Spraying the lumpy gummy insulation mixture evenly onto a web of structural steel, assuming it all dries properly and none is banged off while work proceeds at a gigantic construction site over the course of several years, is an unrealistic expectation. Perhaps this will change, as a "lesson learned" from the disaster. The fatal element in the WTC Towers story is that enough of the thermal insulation was banged off the steel frames by the airplane jolts to allow parts of frames to heat up to 700 C. I estimate the jolts at 136 times the force of gravity at WTC 1, and 204 at WTC 2.

The pivotal conclusion of the NIST fire safety investigation is perhaps best shown on page 32, in Chapter 3 of Volume 5G of the Final Report (NIST NCSTAR 1-5G WTC Investigation), which includes a graph from which I extracted the data in Table 2, and states the following two paragraphs. (The NIST authors use the phrase "critical temperature" for any value above about 570 C, when steel is below half strength.)

"As the insulation thickness decreases from 1 1/8 in. to 1/2 in., the columns heat up quicker when subjected to a constant radiative flux. At 1/2 in. the column takes approximately 7,250 s (2 hours) to reach a critical temperature of 700 C with a gas temperature of 1,100 C. If the column is completely bare (no fireproofing) then its temperature increases very rapidly, and the critical temperature is reached within 350 s. For a bare column, the time to reach a critical temperature of 700 C ranges between 350 to 2,000 s.

"It is noted that the time to reach critical temperature for bare columns is less than the one hour period during which the buildings withstood intense fires. Core columnsthat have their fireproofing intact cannot reach a critical temperature of 600 C during the 1 or 1 1/2 hour period. (Note that WTC 1 collapsed in approximately 1 1/2 hour, while WTC 2 collapsed in approximately 1 hour). This implies that if the core columns played a role in the final collapse, some fireproofing damage would be required to result in thermal degradation of its strength." (3)

Collapse

Airplane impact sheared columns along one face and at the building's core. Within minutes, the upper block had transferred a portion of its weight from central columns in the impact zone, across a lateral support at the building crown called the "hat truss," and down onto the three intact outer faces. Over the course of the next 56 minutes (WTC 2) and 102 minutes (WTC 1) the fires in the impact zone would weaken the remaining central columns, and this steadily increased the downward force exerted on the intact faces. The heat-weakened frames of the floors sagged, and this bowed the exterior columns inward at the levels of the impact zone. Because of the asymmetry of the damage, one of the three intact faces took up much of the mounting load. Eventually, it buckled inward and the upper block fell. (1)

Now, let's explore heat further.

How Big Were These Fires?

I will approximate the size of a level (1 story) in each of the WTC Towers as a volume of 16,080 m^3 with an area of 4020 m^2 and a height of 4 m (4). Table 3 shows several ways of describing the total thermal energy released by the fires.

Table 3, Magnitude of Thermal Energy in Equivalent Weight of TNT

Item WTC 1 WTC 2

energy (Q) 8000 GJ 3000 GJ

# levels 8 6

tons of TNT 1912 717

tons/level 239 120

lb/level 478,000 239,000

kg/m^2 (impact floors) 54 27

lb/ft^2 (impact floors) 11 6

The fires in WTC 1 released an energy equal to that of an explosion of 1.9 kilotons of TNT; the energy equivalent for WTC 2 is 717 tons. Obviously, an explosion occurs in a fraction of a second while the fires lasted an hour or more, so the rates of energy release were vastly different. Even so, this comparison may sharpen the realization that these fires could weaken the framework of the buildings significantly.

How Hot Did The Buildings Become?

Let us pretend that the framework of the building is made of "ironcrete," a fictitious mixture of 72% iron and 28% concrete. This framework takes up 5.4% of the volume of the building, the other 94.6% being air. We assume that everything else in the building is combustible or an inert material, and the combined mass and volume of these are insignificant compared to the mass and volume of ironcrete. I arrived at these numbers by estimating volumes and cross-sectional areas of metal and concrete in walls and floors in the WTC Towers.

The space between floors is under 4 meters; and the floors include a layer of concrete about 1/10 meter thick. The building's horizontal cross-section was a 63.4 meter square. Thus, the gap between floors was nearly 1/10 of the distance from the center of the building to its periphery. Heat radiated by fires was more likely to become trapped between floors, and stored within the concrete floor pans, than it was to radiate through the windows or be carried out through broken windows by the flow of heated air. We can estimate a temperature of the framework, assuming that all the heat became stored in it.

The amount of heat that can be stored in a given amount of matter is a property specific to each material, and is called heat capacity. The ironcrete mixture would have a volumetric heat capacity of Cv = 2.8*10^6 joules/(Centigrade*m^3); (* = multiply). In the real buildings, the large area of the concrete pads would absorb the heat from the fires and hold it, since concrete conducts heat very poorly. The effect is to bath the metal frame with heat as if it were in an oven or kiln. Ironcrete is my homogenization of materials to simplify this numerical example.

The quantity of heat energy Q absorbed within a volume V of material with a volumetric heat capacity Cv, whose temperature is raised by an amount dT (for "delta-T," a temperature difference) is Q = Cv*V*dT. We can solve for dT. Here, V = (870 m^3)*(# levels); also dT(1) corresponds to WTC 1, and dT(2) corresponds to WTC 2.

dT(1) = (8 x 10^12)/[(2.8 x 10^6)*(870)*8] = 410 C,

dT(2) = (3 x 10^12)/[(2.8 x 10^6)*(870)*6] = 205 C.

Our simple model gives a reasonable estimate of an average frame temperature in the impact zone. The key parameter is Q (for each building). NIST spent considerable effort to arrive at the Q values shown in Table 3 (3). Our model gives a dT comparable to the NIST results because both calculations deposit the same energy into about the same amount of matter. Obviously, the NIST work accounts for all the details, which is necessary to arrive at temperatures and stresses that are specific to every location over the course of time. Our equation of heat balance Q = Cv*V*dT is an example of the conservation of energy, a fundamental principle of physics.

Well, Can The Heat Weaken The Steel Enough?

On this, one either believes or one doesn't believe. Our simple example shows that the fires could heat the frames into the temperature range NIST calculates. It seems entirely reasonable that steel in areas of active and frequent burning would experience greater heating than the averages estimated here, so hotspots of 600 C to 700 C seem completely believable. Also, the data for WTC Towers steel strength at elevated temperatures is not in dispute. I believe NIST; answer: yes.

Let us follow time through a sequence of thermal events.


Fireball

The airplanes hurtling into the buildings with speeds of at least 200 m/s (450 mph) fragmented into exploding ******** of burning fuel, aluminum and plastic. Sparks generated from the airframe by metal fracture and impact friction ignited the mixture of fuel vapor and air. This explosion blew out windows and billowed burning fuel vapor and spray throughout the floors of the impact zone, and along the stairwells and elevator shafts at the center of the building; burning liquid fuel poured down the central shafts. Burning vapor, bulk liquid and droplets ignited most of what they splattered upon. The intense infrared radiation given off by the 1100 C (2000 F) flames quickly ignited nearby combustibles, such as paper and vinyl folders. Within a fraction of a second, the high pressure of the detonation wave had passed, and a rush of fresh air was sucked in through window openings and the impact gash, sliding along the tops of the floors toward the centers of intense burning.

Hot exhaust gases: carbon monoxide (CO), carbon dioxide (CO2), water vapor (H2O), soot (carbon particles), unburned hydrocarbons (combinations with C and H), oxides of nitrogen (NOx), and particles of pulverized solids vented up stairwells and elevator shafts, and formed thick hot layers underneath floors, heating them while slowly edging toward the openings along the building faces. Within minutes, the aviation fuel was largely burned off, and the oxygen in the impact zone depleted.


Thermal Storage

Fires raged throughout the impact zone in an irregular pattern dictated by the interplay of the blast wave with the distribution of matter. Some areas had intense heating (1100 C), while others might still be habitable (20 C). The pace of burning was regulated by the area available for venting the hot exhaust gases, and the area available for the entry of fresh air. Smoke was cleared from the impact gash by air entering as the cycle of flow was established. The fires were now fueled by the contents of the buildings.

Geometrically, the cement floors had large areas and were closely spaced. They intercepted most of the infrared radiation emitted in the voids between them, and they absorbed heat (by conduction) from the slowly moving ("ventilation limited") layer of hot gases underneath each of them. Concrete conducts heat poorly, but can hold a great deal of it. The metal reinforcing bars within concrete, as well as the metal plate underneath the concrete pad of each WTC Towers floor structure, would tend to even out the temperature distribution gradually.

This process of "preheating the oven" would slowly raise the average temperature in the impact zone while narrowing the range of extremes in temperature. Within half an hour, heat had penetrated to the interior of the concrete, and the temperature everywhere in the impact zone was between 200 C and 700 C, away from sites of active burning.


Thermal Decomposition -- "Cracking"

Fire moved through the impact zone by finding new sources of fuel, and burning at a rate limited by the ventilation, which changed over time.

Heat within the impact zone "cracks" plastic into a sequence of decreasingly volatile hydrocarbons, similar to the way heat separates out an array of hydrocarbon fuels in the refining of crude oil. As plastic absorbs heat and begins to decompose, it emits hydrocarbon vapors. These may flare if oxygen is available and their ignition temperatures are reached. Also, plumes of mixed hydrocarbon vapor and oxygen may detonate. So, a random series of small explosions might occur during the course of a large fire.

Plastics not designed for use in high temperature may resemble soft oily tar when heated to 400 C. The oil in turn might release vapors of ethane, ethylene, benzene and methane (there are many hydrocarbons) as the temperature climbs further. All these products might begin to burn as the cracking progresses, because oxygen is present and sources of ignition (hotspots, burning embers, infrared radiation) are nearby. Soot is the solid end result of the sequential volatilization and burning of hydrocarbons from plastic. Well over 90% of the thermal energy released in the WTC Towers came from burning the normal contents of the impact zones.


Hot Aluminum

Aluminum alloys melt at temperatures between 475 C and 640 C, and molten aluminum was observed pouring out of WTC 2 (5). Most of the aluminum in the impact zone was from the fragmented airframe; but many office machines and furniture items can have aluminum parts, as can moldings, fixtures, tubing and window frames. The temperatures in the WTC Towers fires were too low to vaporize aluminum; however, the forces of impact and explosion could have broken some of the aluminum into small granules and powder. Chemical reactions with hydrocarbon or water vapors might have occurred on the surfaces of freshly granulated hot aluminum.

The most likely product of aluminum burning is aluminum oxide (Al2O3, "alumina"). Because of the tight chemical bonding between the two aluminum atoms and three oxygen atoms in alumina, the compound is very stable and quite heat resistant, melting at 2054 C and boiling at about 3000 C. The affinity of aluminum for oxygen is such that with enough heat it can "burn" to alumina when combined with water, releasing hydrogen gas from the water, 2*Al + 3*H2O + heat -> Al2O3 + 3*H2. Water is introduced into the impact zone through the severed plumbing at the building core, moisture from the outside air, and it is "cracked" out of the gypsum wall panels and to a lesser extent from concrete (the last two are both hydrated solids). Water poured on an aluminum fire can be "fuel to the flame."

When a mixture of aluminum powder and iron oxide powder is ignited, it burns to iron and aluminum oxide, Al + Fe2O3 + ignition -> Al2O3 + Fe. This is thermite. The reaction produces a temperature that can melt steel (above 1500 C, 2800 F). The rate of burning is governed by the pace of heat diffusion from the hot reaction zone into the unheated powder mixture. Granules must absorb sufficient heat to arrive at the ignition temperature of the process. The ignition temperature of a quiescent powder of aluminum is 585 C. The ignition temperatures of a variety of dusts were found to be between 315 C and 900 C, by scientists developing solid rocket motors. Burning thermite is not an accelerating chain reaction ("explosion"), it is a "sparkler." My favorite reference to thermite is in the early 1950s motion picture, "The Thing."

Did patches of thermite form naturally, by chance, in the WTC Towers fires? Could there really have been small bits of melted steel in the debris as a result? Could there have been "thermite residues" on pieces of steel dug out of the debris months later? Maybe, but none of this leads to a conspiracy. If the post-mortem "thermite signature" suggested that a mass of thermite comparable to the quantities shown in Table 3 was involved, then further investigation would be reasonable. The first task of such an investigation would be to produce a "chemical kinetics" model of the oxidation of the fragmented aluminum airframe, in some degree of contact to the steel framing, in the hot atmosphere of hydrocarbon fires in the impact zone. Once Nature had been eliminated as a suspect, one could proceed to consider Human Malevolence.


Smoldering Rubble

Nature is endlessly creative. The deeper we explore, the more questions we come to realize.

Steel columns along a building face, heated to between 200 C and 700 C, were increasingly compressed and twisted into a sharpening bend. With increasing load and decreasing strength over the course of an hour or more, the material became unable to rebound elastically, had the load been released. The steel entered the range of plastic deformation, it could still be stretched through a bend, but like taffy it would take on a permanent set. Eventually, it snapped.

Months later, when this section of steel would be dug out of the rubble pile, would the breaks have the fluid look of a drawn out taffy, or perhaps "melted" steel now frozen in time? Or, would these be clean breaks, as edge glass fragments; or perhaps rough, granular breaks as through concrete?

The basements of the WTC Towers included car parks. After the buildings collapsed, it is possible that gasoline fires broke out, adding to the heat of the rubble. We can imagine many of the effects already described, to have occurred in hot pockets within the rubble pile. Water percolating down from that sprayed by the Fire Department might carry air down also, and act as an oxidizing agent.

The tight packing of the debris from the building, and the randomization of its materials would produce a haphazard and porous form of ironcrete aggregate: chunks of steel mixed with broken and pulverized concrete, with dust-, moisture-, and fume-filled gaps. Like a pyramid of barbecue briquettes, the high heat capacity and low thermal conductivity of the rubble pile would efficiently retain its heat.

Did small hunks of steel melt in rubble hot spots that had just the right mix of chemicals and heat? Probably unlikely, but certainly possible.

Pulverized concrete would include that from the impact zone, which may have had part of its water driven off by the heat. If so, such dust would be a desiccating substance (as is Portland cement prior to use; concrete is mixed sand, cement and water). Part of the chronic breathing disorders experienced by many people exposed to the atmosphere at the World Trade Center during and after 9/11 may be due to the inhalation of desiccating dust, now lodged in lung tissue.

Did the lingering hydrocarbon vapors and fumes from burning dissolve in water and create acid pools? Did the calcium-, silicon-, aluminum-, and magnesium-oxides of pulverized concrete form salts in pools of water? Did the sulfate from the gypsum wall panels also acidify standing water? Did acids work on metal surfaces over months, to alter their appearance?

In the enormity of each rubble pile, with its massive quantity of stored heat, many effects were possible in small quantities, given time to incubate. It is even possible that in some little puddle buried deep in the rubble, warmed for months in an oven-like enclosure of concrete rocks, bathed in an atmosphere of methane, carbon monoxide, carbon dioxide, and perhaps a touch of oxygen, that DNA was formed.

In part one of this report I discuss the physics of 9/11. In part 3, I address the collapse of WTC 7.

Manuel Garcia a native New Yorker who works as a physicist at the Lawrence Livermore National Laboratory in California with a PhD Aerospace & Mechanical Engineering, from Princeton His technical interests are generally in fluid flow and energy, specifically in gas dynamics and plasma physics; and his working experience includes measurements on nuclear bomb tests, devising mathematical models of energetic physical effects, and trying to enlarge a union of weapons scientists. He can be reached at mango@idiom.com



Endnotes

(web sites active on dates noted)

[1] Manuel Garcia, Jr., "The Physics of 9/11," Nov. 28, 2006,

[2] "Executive Summary, Reconstruction of the Fires in the World Trade Center Towers," NIST NCSTAR 1-5, , (28 September 2006). NIST = National Institute of Standards and Technology, NCSTAR = National Construction Safety Team Advisory Committee.

[3] "Fire Structure Interface and Thermal Response of the World Trade Center Towers," NIST NCSTAR1-5G, (draft supporting technical report G), http://wtc.nist.gov/pubs/NISTNCSTAR1-5GDraft.pdf, (28 September 2006), Chapter 3, page 32 (page 74 of 334 of the electronic PDF file).

[4] 1 m = 3.28 ft; 1 m^2 = 10.8 ft^2; 1 m^3 = 35.3 ft^3; 1 ft = 0.31 m; 1 ft^2 = 0.93 m^2; 1 ft^3 = 0.28 m^3.

[5] "National Institute of Standards and Technology (NIST) Federal Building and Fire Safety Investigation of the World Trade Center Disaster, Answers to Frequently Asked Questions," (11 September 2006)
 
.
The Fall of WTC 7
Dark Fire

By MANUEL GARCIA, Jr.

Bright, windless September morning in Manhattan, looking south and slightly west across Vesey Street from the 12th floor of WTC 7. The eight story US Customs House (WTC 6) lies directly across the way, and beyond it the North Tower (WTC 1), slightly rightward to the west, with the South Tower (WTC 2) even further off, left of WTC 1 to the east.

Then a plane, loud, fast, low, directly overhead flying south; the sun glints off the dimpling of its shiny aluminum painted skin; its 156 ft wingspan over three quarters the width of a Tower face -- puff! The lightning clarity of the moment blinks, the airplane disappears, an orange fireball erupts out of the north face of WTC 1 engulfing its ninth decade of stories. Thinking stops.

Hour = 8:46:30 a.m.; Time = 0.

Hurried calls, nervous chatter, excitement, fear; transfixed, watching the smoke engulf the top of WTC 1; and then another airplane, flying up from the south -- puff!

The plane disappears into the far side of WTC 2, the southern face. A fireball bursts through the north face, consuming the seventh decade of stories. Rocketing debris shoots out of the northeast corner -- this way?! -- it falls short, some whisks past just to the left.

Hour = 9:02:59 a.m.; Time = 16.5 minutes.

In time, the landing gear and an engine thrown out of WTC 2 would be found two and three blocks north, and within a block east of WTC 7. A section of the fuselage from that plane fell atop WTC 5, the nine story North Plaza Building east of the US Customs House. (1)

Some would wonder, "Am I shuddering, or did I feel an earthquake?" Seismometers would record the airplane impacts at local magnitudes 0.9 and 0.7, respectively. (1b), (2)

Phone home, reassure; what to do, work?, only watching out the window is possible, chatter is stunned to silence. People are beginning to jump. Time in front of you is racing, while time for you has stopped. A crack, the top of WTC 2 twists and drops into a gray opacity of billowing powder. The South Tower collapses.

Hour = 9:58:59 a.m.; Time = 1 hour, 12.5 minutes

A blast of dust rushes straight in, the scratching of grit pelting windows and the shattering of glass can be heard, a veil is drawn over the death of a building with too many of its occupants. WTC 7 shakes, magnitude 2.1; over in 10 seconds. (2)

Frantic calls home, some flee, time to lock up the sensitive files and leave before the trains are jammed -- are they still running? Should some of the computer drives be taken along, for security and just in case? Lights go out, power from Con Edison is cut. The emergency generators kick in, power and phones work. Another power fault, then some power returns. Maybe the dust cloud is choking the diesel generator air intakes along Floor 5, and some units are shut down. Crack! -- WTC 1 collapses.

Hour = 10:28:22 a.m.; Time = 1 hour, 42 minutes.

The upper block of WTC 1 drops into the burning impact zone and ejects a cascade of incandescent metal and heated stone laterally, from near the 97th story (368 m), at between 12 m/s (27 mph) to 15 m/s (34 mph) during the 1.5 seconds it takes to fall down to the original height of the 71st story (269 m). (3)

This hot volley, within the overall pyroclastic cannonade discharged by WTC 1 during its collapse, hurtles at 86 m/s (193 mph) at a steep angle down into the face of WTC 7 from Floors 18 to zero. A solid missile -- a hot section of I-beam? -- punches into Floors 11 and 12, bursting through the concrete floors and touching off fires. The elevator shafts at Floors 8 and 9, about 10 to 15 m (33 to 49 ft) into the building, are ruptured and the elevator cars fall out onto the floors. The air pressure wave presses on eardrums, stairwells fill with dust and smoke, and lights go out, the building shakes for nearly 10 seconds; magnitude 2.3. (2)

Time resumes. Some phones are still lit, but they make no connection.

Wandering confused, Floor 7, heavy dust, one cubicle is burning at the west end -- flashlights?, firemen! They lead people down through the choking haze. The lobby is layered in white dust, wires hang from the ceiling, the street is littered with wreckage, a huge cloud rolls all along Vesey Street blocking out the view south.

Hour = noon; Time = 3 hours, 13.6 minutes.

WTC 7 was mortally wounded. In 5 hours and 21 minutes, it would collapse. This article is a visualization of what probably happened. Only gods and the dead have certainty; we, the living, have rationality and courage to guide us through the puzzles and the perils of life.


WTC 7: By The Numbers

WTC 7 was a 176 m (576 ft) tall, 47 story building with a trapezoidal cross section (about): 99 m (325 ft) along the north face, 76 m (249 ft) along the south face, 45 m (148 ft) north-south width, and 47 m (153 ft) along the east and west sides, (4). WTC 7 was about 107 m (350 ft) north of WTC 1, across Vesey Street.

A number of engineering reports have been written about the collapse of WTC 7, because of its uniqueness. A consistent story emerges through the mass of detail. The basic model of the WTC 7 collapse was stated in the earliest report, by FEMA (1c), and increasingly amplified upon by subsequent investigators at NIST -- the National Institute of Standards and Technology, a federal agency within the U.S. Commerce Department's Technology Administration. See footnotes (5), (6), (7) and (8).

WTC 7 was built in 1987 over an existing Consolidated Edison electrical substation. The Con Ed substation was three stories high, and took up the northern half of the footprint of WTC 7. The 1967 construction of the substation accounted for the eventuality of a building above it, and a much larger and stronger foundation was built. Also, a series of columns rose through the area of the substation, for future use.

The design of WTC 7 was larger than anticipated by the provisions of 1967, so additional foundation columns were sunk. Also, the placement of columns in WTC 7 above Floor 7 did not match all the tops of columns connected to bedrock and waiting to be used. Thus, a series of trusses were designed to transfer the vertical loads above Floor 7 and redistribute them laterally to match the waiting columns below Floor 4. This transition used triangular assemblies of structural steel joined into a framework spanning two stories, Floors 5 & 6.

Part of the transition structure included a Floor 5 made of 11 inches of reinforced concrete on top of a 3 inch 18 gage composite metal deck (supported on I beams); Floor 6 was 3 inches of concrete on a 3 inch 20 gage metal deck; the northern half of Floor 7 was 5 inches of reinforced concrete on a 3 inch 18 gage metal deck, and the southern half of Floor 7 was 8 inches of concrete with two layers of reinforcement (no metal deck). Floors 8 and up (except 21, 22, 23) had 2.5 inches of concrete over 3 inch 20 gage metal decks. These metal decks were sheets of metal with corrugations (metal thickness listed by gage number).

The combination of three massive floors and interconnected triangular supports made the framework of Floor 5 to Floor 7 a diaphragm locking WTC 7 together laterally, core columns and walls (encasing elevator shafts and stairwells) to perimeter columns. The construction of WTC 7 above Floor 7 was similar to that of the WTC Towers (9). The irregular framing between Floors 5 and 7 made for less desirable tenant space, but it was well protected by the robust construction, an ideal location for the building's machinery and the emergency power systems.

Machine Space and Emergency Power Systems

Only machinery resided on Floors 5 and 6. Floor 6 had two large cut-outs, one along the east side, another in the southwest corner, to allow for two-story mechanical spaces. A set of louvers spanned the height of Floors 5 and 6 along the eastern face of the building. Table 1 lists the equipment that resided on Floors 5 through 9 (ground level is floor 0).

Table 1, Machinery on Floors 5 to 9, WTC 7

Floor Items

9 1 generator (1 tank) for (tenant) U. S. Secret Service

8 1 generator (1 tank) for (tenant) American Express

7 3 generators (1 tank) for the Mayor's Office of Emergency Management

6 switchgear, storage

5 11 generators (1 tank), switchgear, transformers.

The "tank" noted in the table would be a 275 gallon diesel fuel tank, the maximum size allowed on any given floor by the NYC Building Code.

There were five emergency power systems in WTC 7. Three of them (American Express, OEM, U.S. Secret Service) drew fuel from the other two and larger systems (Salomon Smith Barney, Silverstein Properties). (1c), (8)

The emergency power for the building (Silverstein Properties) was provided by two 900 kW generators on the southwest corner of Floor 5. They drew fuel from a 275 gallon tank nearby, and this was replenished by pumps drawing from two 12,000 gallon tanks at ground level under the loading dock, at the southwest corner of the building.

The SSB emergency power system used nine 1,725 kW generators on Floor 5: three in the southwest corner, two near the west end of the north face, four at the east end of the north face. Louvers for air intake and exhaust were situated on the building faces near the generators. Because there was already a 275 gallon "day tank" on this floor, the SSB system pumped on demand from their own pair of 6,000 gallon storage tanks, also situated under the loading dock, under the southwestern part of the building.

The fuel supplier was contracted to keep the tanks full, and they were full that day.

Fuel pipes for all systems except SSB ran up the western side of the core of the building, along elevator shafts. The SSB pipes ran up a shaft through mechanical spaces near the southwest corner of the building.

Kindling

After 1 p.m. on September 11, 2001, WTC 7 was an evacuated, stricken building. The southwest corner and central third of the south face had been ripped open by the cascading debris from the collapse of WTC 1. Fires burned in sections of Floors 6 through 30 at different times, and they migrated along their floors independently, seeking new sources of fuel. From the street the fires on Floors 11 and 12 appeared most intense. Many fires in the area went unchecked because utility power for electrical pumps, and water pressure for fire engines had either diminished or been lost.

This is what happened.

A Pumped Oil Spill

The debris fall ripping into the southwest corner ruptured the oil pipes of the SSB pressurized fuel distribution system. Operating as intended -- the lack of utility power triggering the "need", and the lack of pressure due to a severed pipe signaling the "demand", the SSB system pumped oil up from its 12,000 gallon basement reservoir, maximally with a pressure of 50 psi (pounds per square inch) and flow rate of 75 gpm (gallons per minute), onto Floor 5.

Pumping would have started at 9:59 a.m., when Con Ed cut utility power to WTC 7; and the spilling would have started a half hour later when the pressurized pipe was cut. The SSB pumps could have drained the two 6,000 gallon tanks in 2 hours and 40 minutes. Engineers from the New York State Department of Environmental Conservation found that "there was a maximum loss of 12,000 gallons of diesel from two underground storage tanks registered as 7WTC." (10)

Additionally, "Both tanks were found to be damaged by debris and empty several months after the collapse. Some fuel contamination was found in the gravel below the tanks and the sand below the slab on which the tanks were mounted, but no contamination was found in the organic marine silt/clay layer underneath." (7)

By contrast, 20,000 gallons of oil was recovered from the two 12,000 gallon tanks of Silverstein Properties. (10)

Pulled up by the emergency pumps, the SSB diesel fuel went , from the 6,000 gallon storage tanks, under the loading dock, under the southwestern part of the building, to floor 5.

It may all have been pumped out by 1 p.m., or it may have been pumped out at a rate as low as 29 gpm for 7 hours. Since this fuel was absent from the wreckage, it was burned. You can see it as the huge plume of black smoke rising from the World Trade Center, in panoramic photographs of that day. Diesel fuel can supply 2.13 MW of power per gpm given an air supply of 1333 cfm (cubic feet per minute). (11)

Thus, a diesel fuel gusher of 75 gpm burning with excess air would produce 160 MW of heat; a total energy of 1536 GJ for the 12,000 gallons. This energy is equivalent to that released by an explosion of 367 tons of TNT. If the pumping rate is lower, or the air supply is throttled, then the burning would occur at a lower rate. Since the louver system along Floor 5 was designed to supply each of the nine SSB engines with 80,000 cfm, it seems likely that a fuel oil fire there would find sufficient air for combustion. For a discussion of heat at 9/11, and energy units, CounterPunchers will soon be able to have my study, "the Thermodynamics of 9/11", to be published shortly on the CounterPunch website as part of our final package on the actual physics and engineering realities of the collapse of the WTC buildings.

The diesel fuel spill spread out along Floor 5, which had been partly shielded from damage by the sturdiness of Floor 7, in addition to its own robustness. The fuel spilled down elevator shafts and breaks near the center of the south face. Floor 4 has a great deal of open space along its eastern two thirds near the south face. Fuel spilling from above would find an easy route to the eastern side of the middle of the building down to Floor 3.

Truss 1, Truss 2 and Truss 3

A bicycle frame is a truss supporting your weight on the axles of the wheels.

A truss is a rigid framework of beams used to support a bridge, roof or floor. The beams in a truss are usually joined so the empty spaces they enclose have triangular and rectangular shapes. A truss transfers the weight it supports along its span, laterally out to its ends where this weight is then carried by columns or foundations into the ground. A truss is how structural engineers shift vertical loads laterally to distant supports. Many railroad bridges are trusses, hollow rectangular space defined by a network of beams joined in a triangulated fashion, and through which trains move.

A folding ladder opened into an "A frame" is a truss. It supports your weight and, say, a can of paint near the top, by transferring the downward force out to the feet of the A. It relies on a horizontal bar connecting the sloping legs to resist the lateral force pushing the A to open and the top to drop.

WTC 7 had three major trusses, two at the eastern end of the building, and one at the western end. These trusses transferred gravity loads carried by columns above Floor 7, laterally to the positions of columns below Floor 4. These trusses supported relatively large floor areas above Floor 7 for the number of columns below Floor 4.

Truss 1 and Truss 2 were aligned roughly along the east-west direction, roughly parallel to each other, and roughly alongside each other when viewed along the north-south direction.

Truss 1 was recessed from the north face by over 1/3 of the width of the building, Truss 2 was recessed from the south face by over 1/3 of the width of the building.

Truss 1 was roughly aligned with the northern edge of the building core as it existed above Floor 7, and Truss 2 was roughly aligned with the east-west centerline of this core.

The northern edge of the mechanical bay on Floors 5 and 6 aligned roughly with Truss 1. Truss 2 aligned with the east-west line bisecting the area of this mechanical bay, but it only extended from the core region to half the distance to the east face.

The eastern end of Truss 2 was a column at the center of the nearly-rectangular space mapped out by the eastern mechanical bay of Floors 5 and 6. This particular column was Column 80. The columns rising out of Truss 2 were Columns 80, 77 and 74, from east to west.

Recall, the pattern of columns below Floor 4 did not match the pattern above Floor 7; for example there was no continuation of Column 77 (middle of Truss 2) below Floor 4.

Truss 3 was another formidable structure, and it occupied a similar zone at the western end of the building; it was aligned in the north-south direction. Diagrams of these trusses may help to visualize the distribution of gravity loads in WTC 7. (13)

Dark Fire

Oil pooled in the vicinity of Truss 2. It was ignited by local office fires, and this burning heated the volumes occupied by the spill, further volatilizing combustible hydrocarbon materials. Air entered the fire through the louver system of Floors 5 and 6, as well as through the opening gouged out of the south face by the debris fall from WTC 1. Air probably entered the south face along Floors 0 to 5, and smoke exhausted up through the south face above Floor 5.

The observation of dense smoke rising out of the south face while the other sides remain clear is consistent with an airflow entry through the east face louvers at Floor 5; combustion of vapors in Floors 3 to 6; heating of the eastern interior of the building; and smoke billowing up through the open atriums and lobbies of Floors 3 and 4, and the breached mid-third of the south face up to about Floor 14. See photos, (14)

Most of the heat generated would be trapped within the heat capacity of the building's structure. The maximum heat we expect here is 1536 GJ, which is half (51&#37;) of that released in the WTC 2 fire (3000 GJ) and one-fifth (19%) of the WTC 1 fire (8000 GJ). (12)

However, the fires in the Towers occurred within larger volumes. Continuing the "ironcrete" example from (12), let us assume that heat is stored in the structure of WTC 7, which is estimated to fill 5.4% of the building volume, and be made of a fictitious homogenization of 72% iron and 28% concrete -- ironcrete -- that has a volumetric heat capacity of Cv = 2.8*10^6 joules/(Centigrade*m^3).

Trapping heat in an ironcrete matrix can be thought of as the charging of a thermal battery.

If the WTC 1 fire was concentrated in 6 stories, with a total volume of 96,480 m^3, then the volume of ironcrete would be 5210 m^3, and its average temperature rise would be 549 C.

If the WTC 2 fire was concentrated in 4 stories, with a total volume of 64,320 m^3, then the volume of ironcrete would be 3473 m^3, and its average temperature rise would be 309 C.

If we assume the oil fire in WTC 7 occurs on the eastern third of the floor space of three floors, then the volume of the oil fire equals that of one floor, which is roughly 15,000 m^3. In this case, the ironcrete volume is 810 m^3, and its temperature rise is 677 C. This estimate assumes all the energy of combustion contained in the fuel oil is released and captured by the structure; clearly, an overestimate.

If we assume that up to half of the combustion energy is lost, because the air is throttled, and because fuel vapors are lost to the atmosphere (as hot, smoky pollution), then we arrive at 768 GJ released within 3 to 7 hours, producing an ironcrete temperature rise of 339 C. Since the flame temperature is about 1100 C (2000 F), we can expect metal supports within continuing fires to heat up by much more than the average amount estimated here.

Table 2, WTC Ironcrete Examples

Item Units WTC 1 WTC 2 WTC 7

energy GJ 8000 3000 768

solid volume m^3 5210 3473 810

energy density MJ/m^3 1536 864 948

temperature rise C 549 309 339

duration minutes 102 56 180-420



The thermal energy density is near 1000 MJ/m^3 in all three examples, which correspond (as highly simplified idealizations) to three buildings that collapsed because of thermal weakening of their frames. Perhaps this observation can help to estimate the risks posed by potential fires elsewhere.

Heat Exhaustion

All of the structural analysis done by FEMA and NIST points to a failure of Truss 1 or Truss 2 -- Truss 2 seems more likely to me -- as the initiating failure in WTC 7. The sequence is as follows:

-> thermal weakening of Truss 2 leads to its failure,

-> the loss of support low in the eastern interior propagates to the roof,

-> the weight (and dynamic force) of material falling onto the diaphragm based on Floor 5 tips this rigid layer of the building,

-> this causes failure of column joints to the diaphragm,

-> lack of vertical support through the diaphragm progresses up the interior of the building west of Truss 2 (and/or Truss 1),

-> the difference in collapse timing east and west of Truss 2 creates a vertical crack/crease/kink/fold/break through the building above Truss 2 (Column 80),

-> a progressive collapse propagates up and material falls freely,

-> since the building implodes, exterior walls falls in.

To sum up:

The blast of hot debris from WTC 1 kindled fires in WTC 7 and caused an emergency power system to feed the burning to the point of building collapse.

One of the building's major bridging supports was heated to the point of exhaustion by the burning of an abundant store of hydrocarbon fuel.

An oil well fire under a loaded bridge.

Part One of my CounterPunch report addresses the Physics of 9/11. Part Two deals with the Thermodynamics of 9/11.

Manuel Garcia a native New Yorker who works as a physicist at the Lawrence Livermore National Laboratory in California with a PhD Aerospace & Mechanical Engineering, from Princeton His technical interests are generally in fluid flow and energy, specifically in gas dynamics and plasma physics; and his working experience includes measurements on nuclear bomb tests, devising mathematical models of energetic physical effects, and trying to enlarge a union of weapons scientists. He can be reached at mango@idiom.com



Endnotes

(web sites active on dates noted)

[1] FEMA 403, "World Trade Center Building Performance Study: Data Collection, Preliminary Observations, and Recommendations, (second printing)," September 2002, (9 October 2006):
[a] Cover & Table of Contents, ,
Chapter 1, "Introduction," (a recommended summary of events; 21 pages of text),
[c] Chapter 5, "WTC 7,(32 pages of text)

[2] "Damage to Buildings near World Trade Center Towers Caused by Falling Debris and Air Pressure Wave, Not Ground Shaking," Earth Institute at Columbia University, 16 November 2001, ,

"World Trade Center Disaster, Seismograms recorded by LCSN Station PAL (Palisades, NY)," ,

"Ripples Spread Wide from Ground Zero," Sid Perkins, Science News, 24 November 2001, ,

(all 9 October 2006)

[3] units conversions: 1 m = 3.28 ft; 1 ft = 0.305 m; 1m/s = 2.24 mph; 1 mph = 0.446 m/s.

[4] "WTC 7," wikipedia, , (8 October 2006).

[5] "Key Findings of NIST's June 2004 Progress Report on the Federal Building and Fire Safety Investigation of the World Trade Center Disaster," 18 June 2004, NIST, , (8 October 2006), note "www" in web address, NOT "wtc," (a few paragraphs on WTC 7).

[6] "Interim Report on WTC 7," June 2004, NIST, http://wtc.nist.gov/progress_report_june04/appendixl.pdf, (8 October 2006), 56 pages (text), (I think Figures L-6 and L-7 have captions switched; Figure L-8 repeats "Floor 2 plan" and Floor 3 plan is not shown.)

[7] "Part IIC - WTC 7 Collapse," NIST presentation April 5, 2005, 42 pages, ( October 9, 2006); shows correct Floor 3 plan, compare to (6)

[8] Raymond A. Gill & Duane A. Johnson, "Documentation of the Fuel System for Emergency Power in World Trade Center 7," NIST NCSTAR 1-1J, September 2005, 74 pages (text), 84 pages (pdf file), , (October 9, 2006).

[9] Manuel Garcia, Jr., "The Physics of 9/11"

[10] ibid.
[11] ibid.
[12] Manuel Garcia, Jr., "The Thermodynamics of 9/11,"
[13] ibid.
[14] ibid.
 
.
Good Science and 9-11 Demolition Theories




This paper is written to demonstrate that those who believe that the World Trade Centre was destroyed by controlled demolition, rather than the impact of the planes, are mistaken. While I sympathise with the overall aims of protesting against US and UK foreign policy, I don't believe that US officials took part in a conspiracy to murder thousands of their fellow-citizens. I believe that the truth is in fact more alarming: US and UK foreign policy is based on ignorance, not malice. But I don't believe in fighting ignorance with ignorance. However well-intentioned, the demolition theories will not achieve their goals because they are based on an ignorance of good science.



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Good Science and 9-11 Demolition Theories



Mike King

Latest revision: 13 May 2007



Disclaimer



I am trained in science but my day job for the last twenty years is in the visual arts. In the material below I have attempted to check and double check facts and calculations, but like all of us am prone to error. I would be delighted to hear from anyone who would like to point out errors of data or calculation, or errors in the flow of argument, and will be pleased to change the text and give appropriate credit. New evidence will undoubtedly come to light over time, and this may alter the known facts and the course of my arguments here or even reverse them. So much the better: I call that good science.

You can contact me at: mike@jnani.org



1 Introduction

1.1 Background

1.2 The Counter-Orthodoxies and Counter-Counter-Orthodoxies

1.3 Motivation

1.4 Jones’s Scientific Evidence and the Science and Practice of Demolition

1.5 Some Basic Concepts in Physics

1.6 What is Good Science?

2 Jones’s Evidence Refuted

2.1 Molten Metal: Flowing and in Pools

2.2 Observed Temperatures around 1000°C and Sulfidation in WTC 7 Steel

2.3 Near-Symmetrical Collapse of WTC 7

2.4 No Previous Skyscraper Collapse Due to Fires

2.5 Squib-timing during the Collapse of WTC 7

2.6 Early Drop of North Tower Antenna

2.7 Eyewitness Accounts of Flashes and Loud Explosions

2.8 Ejection of Steel Beams and Debris-plumes from the Towers

2.9 Rapid Collapses and Conservation of Momentum and Energy

2.10 Controlled Demolition “Implosions” Require Skill

2.11 Steel Column Temperatures of 800°C Needed: A Problem in the Argument of Bazant and Zhou

2.12 Problems in the NIST Report: Inadequate Steel Temperatures and Tweaked Models

2.13 NIST's Failure to Show Visualizations

2.14 Jones’s Summary

3 Additional Arguments for the CD Hypothesis

3.1 Timing of Tower collapses

3.2 Energy Required to Pulverise Concrete

3.3 Seismic Recordings

3.4 Sudden Onset of Collapse ‘Consistent with Demolition’

3.5 Core Columns ‘Should Have Remained Standing’

3.6 Explosions in the Sub-Basement

4 David Ray Griffin and the Dustin Mugford DVD

5 Conclusions






1 Introduction


1.1 Background



The events of 9/11 are widely recognised to be a defining factor in the early unfolding of world history in the 21st century. From this single audacious attack on the US, conflicts in Afghanistan and Iraq flow directly, along with terrorist attacks on Madrid, Bali, and London. Arguably the July 2006 war in Lebanon and the Gaza Strip, waged between Israel on the one side, and Hamas and Hezbollah on the other, is also shaped by the aftermath of 9/11. Domestic and foreign policies of most of the world’s nations have changed as a direct consequence of the attack.



Hence it is of great interest to many different groupings to ascertain the truth of the 9/11 attacks. Broadly speaking there exists the official line, generated by various US Government sponsored investigations, and the counter-orthodoxy, comprising a range of views. On the official side there are three key reports:



1. FEMA (Federal Emergency Management Agency)

2. NIST (National Institute of Science and Technology)

3. 9/11 Commission



Broadly speaking these reports agree that a group of 19 Muslim men, armed only with box-cutters (penknives), hijacked 4 domestic flights, three of which hit their intended targets, and one of which crashed in a field after passengers fought back. AA flight 11 crashed into the North Tower of the World Trade Centre (WTC); UA flight 175 crashed into the South Tower of the WTC; and flight 77 crashed into the Pentagon. The official theory holds that planes which hit the Twin Towers caused structural damage on impact, stripped away insulation from steel columns and severed water sprinklers; caused fires to rage; and eventually they collapsed causing widespread destruction to many other WTC buildings, and, later in the day, the complete collapse of building WTC 7.



Those adhering to the various counter-orthodoxies do not accept that 19 Muslim men, armed only with box-cutters, could achieve such destruction, and believe that the events were part of an official conspiracy. In this paper I will focus mainly on the claims that the Twin Towers and WTC 7 were destroyed by controlled demolition (as part of this conspiracy), rather than the result of the impact of the planes and the subsequent fires. My aim is to show that the scientific basis for these claims is weak or non-existent.



Mostly I will avoid using the loaded term ‘conspiracy theory’ for the counter-orthodoxy, partly because the official account is also, of course, a conspiracy theory. Instead I will use the term ‘controlled-demolition-theory’ or just ‘CD theory’ for the counter-orthodoxy, and the term ‘impact-fire-theory’ or just ‘IF theory’ for the official account, where they deal with the collapse of the WTC buildings.


1.2 The Counter-Orthodoxies and Counter-Counter-Orthodoxies



But who are the groups or individuals challenging the official account? In this paper I focus on a single scientist, Steven Jones, whose work is widely cited by CD theorists, to support their wider challenge to the official line. Another key figure is philosopher and theologian David Ray Griffin, whose two books on the subject are amongst the most radical, and effectively accuse a range of US officials of mass murder. Whole organisations exist however to challenge the official account, including:



* 911Truth.org 911truth.org ::::: The 9/11 Truth Movement
* 9-11 Research 9-11 Research: An Independent Investigation of the 9-11-2001 Attack
* Reopen911.org ReOpen 911 - Welcome to 1984!
* 9-11 Visibility Project www.septembereleventh.org: 9-11 Visibility Project



The events of the day, and the technical details surrounding them are immensely complex, and the counter-orthodoxies have thrown up a wide variety of objections to the official line. I will focus mainly on the controlled-demolition theories, and in particular at the science behind them. What is interesting is that a range of individuals and groups are attacking the counter-orthodoxies, and presenting scientific arguments that refute them. I urge anyone who believes that the argument is merely between the official line and the counter-orthodoxies to look at the following sources which independently argue against the counter-orthodoxies:



* Debunking 911 Debunking 911 Conspiracy Theories and Controlled Demolition Homepage
* Representative Press WTC Pre-Collapse Bowing Debunks 9/11 "Controlled Demolition" Theory
* Snopes http://www.snopes.com/rumors/pentagon.htm
* Popular Mechanics Debunking the 9/11 Myths: Special Report - Popular Mechanics



There is also a crucial paper by Brent Blanchard on the Implosion World website at: http://www.implosionworld.com/Article-WTC STUDY 8-06 w clarif as of 9-8-06 .pdf. This paper alone should end any credulity towards the demolition theory, though its points need more elaboration for a non-technical audience. The reason that I highlight this paper is because it is the only one to date written by an authority on controlled demolition, based on access to data not available to either the official account or the counter-orthodoxy. I consider this paper so important that I would recommend reading it before the rest of this text, or in parallel, as I shall make numerous references to it. In case the link to the Implosion World site should change or be down, I have made the paper available from my site here: Implosion World Paper.



I will draw on the scientific points of the above sites and papers where appropriate.



I want to add here that I think that the publication of books and the existence of websites all devoted to the counter-orthodoxies – which effectively accuse the US Government in general, and range of individuals in particular, of mass murder of fellow-US citizens – are a tribute to Western principles of democracy and freedom of expression. By the same token I am free, along with others, to publish works that challenge the counter-orthodoxies. I want to make it absolutely clear however that I do not support the US Government in its response to 9/11. I simply believe that the approach taken by those who accuse it of complicity in the attacks is misguided. I believe that these accusations will founder on a lack of evidence, and that the same energy could be used to work, using democratic principles, to show where Bush and his colleagues have really gone wrong. I believe this to be their blanket refusal to learn about Islamic culture, history, and tradition; in particular their failure to credit radical Islamic movements their valuable and popular socialist and welfare dimensions; and their attempt to impose Western values on Islamic countries by force.



If you doubt my anti-Bush credentials, please visit a site I created to honour the civilians of Afghanistan killed by US bombing in its subsequent campaign: The Twin Tragedy. I greatly regret not continuing work on this, but I believe that Professor Marc Herold, who supplied most of the statistics, has continued in his efforts to make known that fact that approximately the same number of innocent Afghan civilians died in the US-led invasion as did US civilians in 9/11.


1.3 Motivation



I have spent my academic life researching the intersections between art, science and religion, and have not been drawn up to this point to contemplate in any detail the events of 9/11. However two friends and colleagues have been deeply persuaded of the counter-orthodoxy, principally by Griffin, and to some extent Jones, so I emailed some initial comments objecting in general terms to what I saw, and still do, as a ‘conspiracy theory’ of the worst kind. When I say ‘worst kind’ I mean that the theory betrays the fundamental principles of what I hold good science to be. My first degree was a joint honours in Physics and Chemistry, and later on I completed an MSc in Software Engineering and have written hundreds of thousands of lines of code for big graphics programmes. Jointly these experiences have persuaded me that ‘Good Science’ is a matter of slow and careful investigation of data, with the continual awareness that one’s own emotional commitment to one result or another tends to make it overwhelmingly tempting to jump to conclusions ahead of the due process. Debugging large software programmes is very similar to the detective work in crime investigations, only one is personally the ‘criminal’ and even more likely to have an investment in one’s theories. Looking at the writings of those challenging the official line, I find little evidence of good science in this sense: it seems that the individuals promoting these ideas are already persuaded of their version of the ‘truth’. My interest in 9/11 is therefore partly personal – I am hoping to dissuade my friends of their adherence to the counter-orthodoxies – and partly that I believe in ‘Good Science’ as the basis for much more than academic arguments over the interpretation of events. I believe in ‘Good Science’ as fundamental to what we cherish, though often without naming them such, as ‘Enlightenment Values.’


1.4 Jones’s Scientific Evidence and the Science and Practice of Demolition



In Section Two I will focus on the scientific evidence put forward by Professor Steven Jones in his online paper at http://www.physics.byu.edu/research/energy/htm7.html entitled “Why Indeed Did the WTC Buildings Collapse?” He presents his evidence under 13 headings, though in fact some include additional points, and some are effectively subsumed under other headings. His evidence is meant to convince us that the Twin Towers and WTC 7 were brought down by controlled demolition, meaning the use of explosives triggered in a sequence similar to that used in legitimate explosive demolition. The bulk of this paper is devoted to Jones’s 13 headings, showing in detail why I think he is wrong on every count.



I believe, as a scientist, that Jones’s principal error is not to research the science and practice of explosive demolition. It is quite understandable when lay persons repeat the oft-cited 9/11 opinion: ‘it looked like controlled demolition.’ A good example is Hollywood actor Charlie Sheene recounting his reaction to 9/11 in a TV interview: ‘I said, “call me insane, but did it sorta look like those buildings came down in a controlled demolition?”’ (You can see this in a DVD distributed by one of the counter-orthodoxy groups, 911revisited.com at www.911revisited.com; I comment on the DVD in section Four of this paper.) But it is the job of a scientist not to be fooled by appearances: a scientist knows that fool’s gold isn’t gold and the leaf-moth isn’t a leaf. A physicist also knows well that much of physics is deeply counter-intuitive, for example that heavy bodies fall at the same speed as light ones, that the earth rotates, is round, etc.



I will now sketch an outline of the science and practice of explosive demolition, though the finer points will become apparent in the arguments to follow. First of all, the art of bringing a tall building down by the use of explosives is not a widely disseminated field of engineering, being rather the specialist domain of a few dozen top international companies, often family-run. Hence there are not many books on the subject, and the Internet now is more likely to point to Jones’s paper on the subject than any useful technical review.



However, the web site How Stuff Works (HowStuffWorks "Science Channel") has a short section on explosive demolition that is informative, and begins with this description:



The basic idea of explosive demolition is quite simple: If you remove the support structure of a building at a certain point, the section of the building above that point will fall down on the part of the building below that point. If this upper section is heavy enough, it will collide with the lower part with sufficient force to cause significant damage. The explosives are just the trigger for the demolition. It's gravity that brings the building down.



The key physics is elucidated here: that it is gravity which brings the building down. More than that, it is gravity that smashes concrete walls and floors into rubble, and it is gravity that is responsible for the sometimes vast clouds of dust and debris that billow out from the site. The explosives used have a marginal additional effect in converting the structure into rubble and dust: their job is to cut supports, often in a carefully timed sequence. Brent Blanchard puts it like this: 'Since their inception in the late 1800s, blasting engineers have understood that building implosions work best when the forces of gravity are maximised. This is why blasters always concentrate their efforts on the lowest floors of the structure. While smaller supplemental charges can be placed on upper floors to facilitate breakage and maximize control as the structure collapses, every implosion ever performed has followed the basic model of obliterating structural supports on the bottom few floors first, "to get the structure moving."'



Two types of explosive demolition are carried out: ‘toppling’ and ‘implosion’. Toppling involves the placing of explosive charges to cut out the support structure on one side only of a building, causing the structure to rotate as it collapses, generally into an open lot where it can do no damage. Implosion involves the more symmetrical placing of charges in order to bring the building down symmetrically into its own ‘footprint’. It is the near-symmetrical collapse of the Twin Tower and WTC 7 that has drawn many lay observers to the belief that they were brought down by controlled explosive demolition – ‘implosions’ that could only be achieved by very skilled operators. Unfortunately for the CD theorists the skilled operators – those in the business of carrying out implosions on contracts worth millions of dollars – don’t share this belief.


1.5 Some Basic Concepts in Physics



Readers can skip this for now, but I want to outline some very simple and fundamental concepts in physics needed to negotiate the scientific claims and counter-claims of the IF and CD theories. (I promise that this is very brief and easily accessible to the lay person.)



The first is that when an object is raised to a height, it gains what is known as gravitational potential energy. As Loizeaux says: “Every nail that was carried up in the pocket of some construction worker is potential energy that’s at our disposal, …” In terms of physics the potential energy is calculated by the formula



E = mgh



E is the energy, m is the mass (of the nail or any other object), g the acceleration due to gravity, and h the height that the object is raised. If m is in kilograms, g in metres per second per second, and h in metres, then E is measured in a unit called Joules. When the Loizeaux family demolish a building in an implosion they are liberating this stored potential energy as kinetic energy – the energy of movement. This energy is calculated by a different formula:



E = ½ mv2



In this case the kinetic energy in Joules is equal to half the mass of the moving object times the velocity squared. When the collapsing building hits the ground the kinetic energy is converted into other forms, such as fracture energy (energy required to break, for example, concrete into rubble), sound energy, and heat energy. To give some pertinent examples, the gravitational potential energy (mgh) of one of the Twin Tower has been estimated at 1.139 x 1012 Joules. This is roughly 1 followed by 12 noughts or a billion times a billion Joules (an American trillion). To put that in perspective, it is roughly the same energy as 272 tons of TNT exploding, or enough to melt one thousand metric tonnes of steel. The impact of the faster of the two planes released kinetic energy (½ mv2) roughly equal to 4 x 1009 Joules, or four thousand million Joules. This is enough to melt approximately 4 metric tonnes of steel.



Of course, the energy released by the collapse of the Towers or the impacts of the plane did not go into melting tonnes of steel (though a small fraction may have). The point here is to understand the colossal energies involved in the WTC disaster, and how they are estimated in physics. Also vital to understand is the law of conservation of energy, which requires that all the energy that disappears in one form must appear in an other form or forms.



We will see that a key debate in the IF vs. CD theory is as to whether there was enough gravitation potential energy (mgh energy) in the buildings to account for the pulverisation of them into such fine dust and rubble. It is also helpful to be able to compare the mgh energy of the buildings to any proposed energy that the CD theorists believe to have come from explosives.



The additional scientific concept that needs to be introduced is more nebulous, but critical: it is complexity theory (also broadly called chaos theory). While pure physics (of the kind that Newton’s revolution in science introduced to the world) deals with very simple systems, the real world is not just a bit more complicated: it is orders of magnitude more complicated. Newton was able to make his stunning breakthrough in astronomy (in brief, the inverse square law of gravitation) because he focussed on two bodies at a time, i.e. the sun and any given planet, or a planet and its moon. It is well known in physics that the introduction even of a third body to the problem makes the mathematics almost intractable. If we scale up the problem to a natural event like the collapse of the Twin Towers, then we are dealing with a vast number of bodies interacting with each other. Chaos theory tells us a very sobering fact about a complex system like this: minute variations in the input factors for a complex system lead to wildly varying outcomes. This is why explosive demolition is part science, but also part art. Like all experts in real-world events, implosionists are masters of their total body of experience, constituting what influential writer Donald Schon has called ‘tacit knowledge.’ When CD theorists cite as evidence that ‘no steel-framed building has ever collapsed before as a result of fire’ they are ignoring complexity theory, which requires only that small differences in the original parameters result in a novel outcome. The question we shall explore is whether the impact of a passenger jet into a steel-framed building makes that ‘small’ difference or not.


1.6 What is Good Science?



For me, good science is far more than accurate science. ‘Accurate representation’ for philosopher Richard Rorty is ‘simply an automatic and empty compliment which we pay to those beliefs which are successful in helping us do what we want to do.’ [Rorty, Richard, Philosophy and the Mirror of Nature, Princeton, New Jersey: Princeton University Press, 1979, p. 10] I find this quintessentially postmodern approach to science not just inadequate but actually painful: my love of science has been lifelong and born out of its extraordinary ability to penetrate the world of appearances and find laws whose predictive powers are the basis of our modern technological lifestyles. More than just ‘helping us do what we want to do’ however, I believe that the birth of science with Newton and others was the genuine basis for the Enlightenment and the values that flowed from it and which are the basis of what is best in the modern world. Above all, science taught the great thinkers of the Enlightenment that there was a way beyond personal prejudice and superstition in the settling of the affairs of society, a way of settling dispute based on evidence. Difficult as this path is, there lies an even more important lesson from science: when the evidence is not available then we are obliged to say: we don’t know. Science is not often promoted as the discipline which teaches us what we don’t know, but for me that is the essence of good science. The Witchfinder General only allowed the possibility that the accused man or woman was a witch or was not. ‘We don’t know’ was not an option, and the most absurd evidence was concocted to fill the vacuum.



For us to really know something in science we have to start with a simple system, isolate it from variables that enter from outside, and above all, be able to repeat the phenomenon under scrutiny. The WTC attack is as far removed from this as one can get. Only identical structures under identical impacts could form the basis for certain knowledge as to whether or not the impacts could cause the collapses. But when we examine both the wilder and the more sober adherents to the counter-orthodoxies and to the controlled demolition theory, we find a universal unwillingness to accept that ‘we don’t know’ what happened. Not at least with the kind of certainty available to the phenomenon in controlled laboratory experiments.



The most common complaint from the counter orthodoxy is ‘I can’t believe that …’ followed by a specific from the event. For example eye-witness accounts confirm that after impact on WTC 2 a blast blew out windows in the ground floor lobby and hurled people to the ground. The official account suggests that the kerosene-air mixture from the impact zone high up in the tower was forced down the lift shafts and other ducting by a fireball, causing the damage. Martin Sheene, speaking in the same TV interview, said: ‘I have a hard time believing that a fireball travelled down the elevator over 1100 feet and still had the explosive energy to destroy the lobby like it was described.’ One can sympathise with this point of view, but good science goes beyond pub talk like this: it starts by not pre-judging. Instead it investigates.



I need to make another point on good science here: the question of publication in refereed journals. The CD theorists are largely drawing on unpublished scientific papers. There is of course good science that is refused publication, and there is of course bad science that does get published, but these are exceptions, and on the whole what publication means is that experts in the field have checked the assumptions, experimental procedures, calculations, and flow of the argument that make up the paper. Even the most polymathic of scientists find this difficult to do outside of their own discipline.


2 Jones’s Evidence Refuted



This section refers to Professor Steven Jones’s paper, widely available on the Internet, for example at: http://www.physics.byu.edu/research/energy/htm7.html. It is worth having this to hand in following the arguments in this section. I have used his thirteen section headings verbatim. Jones gives a summary of his argument at the beginning of his paper, but I will start with the detailed arguments in the sections that follow the summary.


2.1 Molten Metal: Flowing and in Pools



Eye-witness accounts of the presence of molten metal at high temperatures in the basement rubble of the Twin Towers and WTC7 have led Jones to speculate that the industrial compound thermite was responsible, and is hence evidence for the CD theory.



Jones: “I maintain that these observations are consistent with the use of high-temperature cutter-charges such as thermite, HMX or RDX or some combination thereof, routinely used to melt/cut/demolish steel.”



But thermite is an incendiary, a vastly different product to HMX and RDX which are military explosives like TNT that can be used in civilian demolition projects. Thermite is a slow-burning product in comparison, does not explode, and, as far as I can determine, is never used in demolition of buildings. It can be used to melt horizontal pieces of steel, because it produces molten iron at up to 2,500 degrees centigrade, which flows onto the target and melts it. It cannot be used to melt vertical structures, because the molten iron simply flows past the target. Thermite is used to quietly destroy military equipment such as artillery (by inserting it down an up-pointing barrel), but more regularly in construction, for example, to weld rails together.



Hence the CD theory is not supported by the quantities of molten metal, because thermite in its conventional form is useless in demolition: it is slow-burning, with unpredictable time to melt, and can only be used in direct contact with horizontal unclad steel beams / components. (The horizontal steel members in the Twin Towers were covered by at least 4 inches of concrete.) Prototype thermite cutter torches have been developed which could cut steel at any angle, but they work by producing as stream of high-velocity, high-temperature combustion products. Any iron produced by such a cutter would be dispersed as as droplets and would only in exceptional circumstances pool into any significant quantities of molten iron. It is more likely that a film of iron particles, mixed with aluminium oxide particles, would be deposited on nearby surfaces. However this is speculation on my part as I cannot find any reference to commercially available thermite cutter torches. If anyone can provide information on such devices I would be pleased to hear from them. Nano-thermites, mentioned by Jones, are also ruled out because they operate more like an explosive, and so would disperse iron particles as I suggest above. The thermite lance, a variant that uses a long iron tube with aluminium rods running through it, is ruled out as far as I can tell because it would require an operative.

HMX or RDX on the other hand, which can be used in demolition (though TNT seems to be more common), would not melt steel, because the high energy content of the material is released in very short timescales, designed, not to melt the target, but to fracture it.



Jones: “Observe the grayish-white plumes trailing upward from white "blobs" at the left-most extremities of the upper structure. (The lower structure is mostly obscured by dust.) It is possible that thermite cut through structural steel and that what we now observe is white-hot iron from the reaction adhering to the severed ends of the steel, with grayish-white aluminum oxide still streaming away from the reaction sites. The observations are consistent with the use of thermite or one of its variants.”



In the photograph provided there is only one white blob on the left-most extremity of the upper structure. Grayish white plumes seem to come from the whole structure, not the blob, and could be any kind of ash or powder. There is no significant resemblance either to the plumes emitted from the bag of thermite in Jones’s accompanying photo. Indeed the plumes in the WTC photo are indistinguishable from the billowing clouds of dust and debris around them.



More easily visible, and the subject of debate, is the stream of what looks like molten metal running from WTC 2 just below the impact zone.



Jones: “Who can deny that liquid, molten metal existed at the WTC disaster? The yellow color implies a molten-metal temperature of approximately 1000 oC, evidently above that which the dark-smoke hydrocarbon fires in the Towers could produce. If aluminum (e.g., from the plane) had melted, it would melt and flow away from the heat source at its melting point of about 650 oC and thus would not reach the yellow color observed for this molten metal. Thus, molten aluminum is already ruled out with high probability.”



To rule out aluminium so quickly is poor science, because we don’t know what the temperatures were in the impact zone, while we do know that many metric tonnes of aluminium constituting the plane were in the area just above the outflow of molten metal. Of course, the alternative hypothesis, that the molten metal was iron or steel, should be also considered carefully. The argument of Jones is that if the molten metal were steel, then it would support the CD theory. But the link between molten steel and controlled demolition is non-existent, as thermite is not used in controlled demolition. Hence Jones requires a variation on controlled demolition: controlled demolition plus the use gratuitous and incompetent use of thermite. We have to believe that the conspirators had researched controlled demolition so badly as to decide on the use of thermite. Now, Jones estimates that “Roughly 2,000 pounds of RDX-grade linear-shaped charges” would be sufficient to bring the building down, and such a quantity of explosive might conceivably have been hidden in each of the towers. But the quantity of thermite required to produce this stream of molten metal is much greater. 107 Kg of thermite is required to produce 54 Kg of molten iron, and the stream of molten metal flowing from the impact zone (if iron) has been estimated at thousands of kilograms. Even if the stream is only 1,000 kg of iron, then 2,000 kg, or two metric tonnes, of thermite would be required. But the CD hypothesis implies much more than this. For a start the thermite would have been distributed over the proposed target floor for initial collapse, so it would be very difficult for the molten iron products to pool in one place and pour out. Secondly, the CD hypothesis agrees that the floor(s) of impact of the plane could not have been exactly predicted, so every, say, 5 floors, another couple of metric tonnes of thermite would be required. (Jones: ‘… to make it appear that the planes somehow initiated the collapse; cutter-charges could have been pre-placed at numerous spots in the building, since one would not know exactly where the planes would enter.’) Even if only the top half of the building were so prepared, then we would anticipate 2 metric tonnes x 11 locations or 22 tonnes. If the mass of stream of molten metal were estimated at more like 10,000 kg of iron then the figure goes up to 220 tonnes of thermite. We have to believe (a) that the conspirators were ignorant enough to attempt to use thermite, and (b) could insinuate between 22 and 220 tonnes of thermite, plus charges, plus radio firing systems, into each tower.



If in addition, thermite is required by the CD hypothesis to account for the molten steel in the basement after collapse, then we have to add an addition two tonnes of thermite for every tonne of molten iron. The problem for the CD theory is in fact that no reliable estimates exist of the amount of molten metal, if any, in the basements.



To sum up, it is a tough job to for the CD hypothesis to account for the stream of molten metal as iron produced from thermite reaction because (a) the choice of thermite requires the conspirators to be incompetent, (b) pooling of the molten iron would require the odd concentration of thermite on a given floor in one location, and (c) the quantity needed (22-220 tonnes) would be hard to smuggle in and hide in the building. This quantity increases by two tonnes per every tonne of molten steel estimated to be in the basements.



The IF hypothesis suggests that the molten metal is aluminium (and other alloys used in plane construction), and that it pooled in that location because that is where the plane was. As Jones rightly point out however, the IF hypothesis would require the molten aluminium (and alloys) to attain temperatures several hundred degrees above melting point. The IF hypothesis also requires that the molten steel in the basement have been heated by a combination of fire and mgh energy, so much rests on estimates of those factors.



I want to add a hypothesis that may yet explain the high temperatures, and would need to be disproved by the CD theorists: that some of the aluminium in the planes was ignited on impact. I return to this issue later on.


2.2 Observed Temperatures around 1000°C and Sulfidation in WTC 7 Steel



In Jones’s second section, he continues on the themes of high temperatures:



Jones: “combines aluminum/iron oxide (thermite) with barium nitrate (29%) and sulfur (typically 2% although more sulfur could be added). The thermate reaction proceeds rapidly and is much faster than thermite in degrading steel leading to structural failure. Thus, both the unusually high temperatures and the extraordinary observation of steel-sulfidation (Barnett, 2001) can be accounted for -- if the use of thermate is allowed in the discussion.”



I would suggest that the argument against thermite I presented above applies equally to thermate. Certainly, the sulfidation of steel is an additional argument in favour of thermate, but is mitigated against because of the difficulty of maintaining contact between thermate sulphur-rich molten-iron products and steel columns. Molten iron flows very fast, due to its high density, and would have only very short contact times with vertical steel members, which would have had to have their insulation previously stripped. We are left again with the issue of the thermite / thermate molten iron products perhaps pooling on an exposed horizontal steel member long enough to cause melting and sulfidation, unlikely because the horizontal members were covered in at least 4 inches of concrete.



Jones says: “While gypsum in the buildings is a source of sulfur, it is highly unlikely that this sulfur could find its way into the structural steel in such a way as to form a eutectic.” But why is this more unlikely than with thermate? Jones needs to present evidence that steel girders or columns, when exposed to burning thermate, result in sulfidation, and that the high temperatures and pressures of the collapse could not achieve sulfidation with the sulphur contained in gypsum (plaster). There are certainly interesting scientific questions here to which we don’t know the answers. But our ignorance is equal as to the two proposed processes, so at present we should marginally favour the theory that has a known source of sulphur: the gypsum.



You may like to look at the ‘Rethinking Thermite’ pages on the Debunking 911 site for further arguments against Jones’s hypothesis (Thermite and Sulfer- Debunking 9/11 Conspiracy Theories and Controlled Demolition).

In Brent Blanchard's paper he devotes section 5 to the issue of thermite and molten metal. His team spoke directly to operators who cleared Ground Zero, and he concludes: 'To a man, they do not recall encountering molten structural steel beams, nor do they recall seeing any evidence of pre-cutting or explosive severance of beans at any point during debris removal activities.'


2.3 Near-Symmetrical Collapse of WTC 7



The collapse of WTC 7 building, which was not hit by planes is one of the more enduring mysteries of 9/11. The counter-orthodoxy argues that a 47 story steel-framed building with small falling debris damage and low-grade fires burning for only 7 hours should not have collapsed. Suspicions are also fuelled by the fact that NIST has yet to complete its report on the building. Jones draws attention to one of the features of its collapse:



Jones: “WTC 7 collapsed rapidly and nearly-straight-down symmetrically -- even though fires were randomly scattered in the building. WTC 7 fell about seven hours after the Towers collapsed, even though no major persistent fires were visible (considerable dark smoke was seen). ”



I believe that the near-symmetry of the WTC 7 collapse is overstated in the CD theories. An aerial view of the site after collapse shows the north façade of the building neatly folded on top of the rubble, suggesting that the front of the building, which had received severe damage, collapsed ahead of the rear, which had no damage. As the front of the building fell, it pulled the rear down on top of the debris. It is also rather vague to say that “no major persistent fires were visible” – such a statement does not lead to quantifiable assessments of thermal heat production or temperatures. The photograph below shows the ‘considerable dark smoke’ pouring from the building: is this not due to a major fire?





I am indebted to the Debunking 911 site for this image, and recommend reading the entire page devoted to this issue: Debunking 9/11 Conspiracy Theories and Controlled Demolition - World Trade Center 7, Building 7. The face of the building (WTC 7 is the pink-coloured one) from which smoke is pouring is the south face damaged by debris falling from WTC 1. (I recommend watching the video of WTC 7 burning, available on the same webpage.)



But in any case why should we accept from Jones that “no major persistent fires were visible” even if this has become the mantra of the counter-orthodoxy? Wouldn’t the eye-witness testimony of experienced New York firefighters count for more?



Captain Chris Boyle (Engine 94) with 18 years of service with the FDNY gave this interview:

Firehouse: Did that chief give an assignment to go to building 7?

Boyle: He gave out an assignment. I didn’t know exactly what it was, but he told the chief that we were heading down to the site.

… We went one block north over to Greenwich and then headed south. There was an engine company there, right at the corner. It was right underneath building 7 and it was still burning at the time. They had a hose in operation, but you could tell there was no pressure. It was barely making it across the street. Building 6 was fully involved and it was hitting the sidewalk across the street. I told the guys to wait up.

A little north of Vesey I said, we’ll go down, let’s see what’s going on. A couple of the other officers and I were going to see what was going on. We were told to go to Greenwich and Vesey and see what’s going on. So we go there and on the north and east side of 7 it didn’t look like there was any damage at all, but then you looked on the south side of 7 there had to be a hole 20 stories tall in the building, with fire on several floors. Debris was falling down on the building and it didn’t look good.

But they had a hoseline operating. Like I said, it was hitting the sidewalk across the street, but eventually they pulled back too. Then we received an order from Fellini, we’re going to make a move on 7. That was the first time really my stomach tightened up because the building didn’t look good. I was figuring probably the standpipe systems were shot. There was no hydrant pressure. I wasn’t really keen on the idea. Then this other officer I’m standing next to said, that building doesn’t look straight. So I’m standing there. I’m looking at the building. It didn’t look right, but, well, we’ll go in, we’ll see.

So we gathered up rollups and most of us had masks at that time. We headed toward 7. And just around we were about a hundred yards away and Butch Brandies came running up. He said forget it, nobody’s going into 7, there’s creaking, there are noises coming out of there, so we just stopped. And probably about 10 minutes after that, Visconti, he was on West Street, and I guess he had another report of further damage either in some basements and things like that, so Visconti said nobody goes into 7, so that was the final thing and that was abandoned.

Firehouse: When you looked at the south side, how close were you to the base of that side?

Boyle: I was standing right next to the building, probably right next to it.

Firehouse: When you had fire on the 20 floors, was it in one window or many?

Boyle: There was a huge gaping hole and it was scattered throughout there. It was a huge hole. I would say it was probably about a third of it, right in the middle of it. And so after Visconti came down and said nobody goes in 7, we said all right, we’ll head back to the command post. We lost touch with him. I never saw him again that day.

Firehouse.com's 9-11 Coverage: News 9/9/02 - WTC: This Is Their Story



Here is an extract from the testimony of Deputy Chief Peter Hayden, who had 33 years service in Division 1 to his credit:



Firehouse: Other people tell me that there were a lot of firefighters in the street who were visible, and they put out traffic cones to mark them off?



Hayden: Yeah. There was enough there and we were marking off. There were a lot of damaged apparatus there that were covered. We tried to get searches in those areas. By now, this is going on into the afternoon, and we were concerned about additional collapse, not only of the Marriott, because there was a good portion of the Marriott still standing, but also we were pretty sure that 7 World Trade Center would collapse. Early on, we saw a bulge in the southwest corner between floors 10 and 13, and we had put a transit on that and we were pretty sure she was going to collapse. You actually could see there was a visible bulge, it ran up about three floors. It came down about 5 o’clock in the afternoon, but by about 2 o’clock in the afternoon we realized this thing was going to collapse.



Firehouse: Was there heavy fire in there right away?



Hayden: No, not right away, and that’s probably why it stood for so long because it took a while for that fire to develop. It was a heavy body of fire in there and then we didn’t make any attempt to fight it. That was just one of those wars we were just going to lose. We were concerned about the collapse of a 47-story building there. We were worried about additional collapse there of what was remaining standing of the towers and the Marriott, so we started pulling the people back after a couple of hours of surface removal and searches along the surface of the debris. We started to pull guys back because we were concerned for their safety.



Firehouse.com's 9-11 Coverage: News 9/9/02 - WTC: This Is Their Story



I believe that the testimony of experienced fireman ought to give most sober-minded people very serious doubt about the CD hypothesis, in particular the account of the sagging of the building prior to collapse, the assertion by Hayden that it was a heavy fire, and the testimony regarding lack of water pressure to fight the blaze.



Boyle’s report suggested that the debris caused a huge gash of twenty storeys in that face, which would allow for the flow of air to the fires simply unprecedented in fires in similar buildings.



All the evidence suggests that WTC 7 was unique in the history of fire-fighting because (a) structural damage was extensive, (b) vast openings in the south face allowing unimpeded airflow, (c) water mains had been severed by the collapse of the Towers, and hence almost no water was available to the Fire Service, and (d) the Fire Service had anyway made the eminently reasonable policy decision that their priority was to save lives not buildings, so it burned for 7 hours virtually unattended. Also, the bulging of the building prior to collapse is also prime evidence against the CD theory, because controlled demolition never produces such bulges.



In this section Jones also wants to argue that the fine rubble produced in the WTC 7 collapse is evidence of explosives:



Jones: By contrast, concrete floors in the Twin Towers and WTC 7 were pulverized to dust -- as is common in controlled demolitions using explosives.



But we have already pointed out that concrete floors, if they are pulverised to dust in controlled demolition, are pulverised due to gravity, not explosives. This is a core mistake repeated by Jones and other CD theorists.

Brent Blanchard deals with WTC 7 in section 7 of his paper. He refutes the claim that the owner of WTC 7 had any role in its collapse, and also says: 'Any detonation of explosives within WTC 7 would have been detected by multiple seismographs monitoring ground vibration in the general area. No such telltale "spike" or vibratory anomaly was detected by any recording instrument.' I will return to the issue of seismic data in section 3.3.


2.4 No Previous Skyscraper Collapse Due to Fires



This is one of the leading arguments in favour of the CD hypothesis, and the counter argument states that no previous skyscraper had been hit by an airliner. In the case of WTC7 the counter argument goes that it (a) it suffered severe structural damage from falling debris, and (b) fires raged for 7 hours in it, with no significant fire-abatement effort. In the differing cases of the towers and building 7, the IF theory has to show that structural damage (including insulation displacement) plus fire is an adequate account. Hence the CD theorists must present evidence to show that the IF account is inadequate, by denying the magnitude of both the structural damage, and the intensity of the fires. Too much of the argument either way on this issue is mere opinion, so the best science here is to return to issues that have a clearer empirical basis.


2.5 Squib-timing during the Collapse of WTC 7



For many CD theorists, the ejection of puffs of smoke and other debris during collapse is a sure sign of the use of explosives.



Jones: “Horizontal puffs of smoke and debris are observed emerging from WTC-7 on upper floors, in regular sequence, just as the building starts to collapse. (The reader may wish to view the close-up video clip again.) The upper floors have evidently not moved relative to one another yet, from what one can observe from the videos. In addition, the timing between the puffs is less than 0.2 seconds so air-expulsion due to collapsing floors (see Chertoff, 2005) is evidently excluded. Free-fall time for a floor to fall down to the next floor is significantly longer than 0.2 seconds: the equation for free fall, y = ½ gt2, yields a little over 0.6 seconds, as this is near the initiation of the collapse.”



Jones is referring to videos of WTC 7 collapse which show dark markings on the right of the top of the building, as in the 2nd image below. They are nothing like as regular in sequence as he proposes, and he uses video footage which focuses in just on the top right instead of the whole building. In the two frames below it is clear that dark markings appear erratically over the building, and in no sequence that could possibly suggest controlled demolition.





Descent initiated


In descent: note the appearance of small dark patches across the building.





The Debunking 911 site devotes a page to this at Debunking 9/11 Conspiracy Theories and Controlled Demolition - Squibs where it is suggested that the specific locations of the dark markings Jones refers to is in fact due to impact damage on that corner of the building:





I am grateful to the Debunking 911 site for this image, and the suggestion that we are looking at damaged panels flapping about, rather than at ‘squibs.’ The photograph of the damage to WTC 7 so high on the building also helps us understand the extent of the damage to the whole of the south façade, which we do not apparently have other photographic records of.



In the video the upper ten or so storeys are moving downwards as one, so air-expulsion originating from within these floors is ruled out, but not because of the timings Jones cites. Instead, it is obvious that if there was air-expulsion of debris and fine dust would be generated by the pancaking taking place far below, rather than within these levels. The ‘puffs’, travelling up the ten or so storeys visible in the video could not come from the upper storeys, but could come from pressure build up below expelling material up a shaft or stairwell, and out horizontally where there were open corridors or other relatively unimpeded flow ways, or, more simply, as Debunking 911 says, causing previously damaged panels to flap about. It would be impossible to put the timing constraints that Jones suggests on these ‘squibs’ because one would need a precise hydrodynamic model of the overpressures working their way through the collapsing structure.



Jones: “However, the presence of such “squibs” proceeding up the side of the building is common when pre-positioned explosives are used, as can be observed at ImplosionWorld.com The same site shows that rapid timing between explosive squibs is also common.”



Jones is right to say that “rapid timing between explosive squibs is also common” (often down to microseconds) but he fails to notice the much bigger timing issue in controlled demolition. Any detonations on upper floors are designed, not to bring the building down, or accelerate its progress, but to ‘teach’ the building how to collapse, once it starts descending. As such, the explosions on upper floors take place in the fractions of seconds prior to the main descent of the building, not during it.



Jones also appears to believe that such ‘squibs’ running up a building are common, as if it confirms for him that demolition proceeds by progressively cutting away floors in a progressive upward fashion. This is simply not true, necessary, or possible in conventional explosive demolition. Jones would also need to account for the overall pattern of dark patches appearing across the building as it descended, which he ignores.



Jones: “Thus, squibs as observed during the collapse of WTC 7 going up the side of the building in rapid sequence provide additional significant evidence for the use of pre-placed explosives.”



Even by using the term ‘squib’ Jones has pre-judged the hypothesis, because ‘squib’ means firework or explosive. The puffs of smoke are however no evidence of controlled demolition, because controlled demolition simply does not require explosive charges to go off at this point, and in such a sequence. The timing and sequence can, however, be explained by the ejection of debris in the crumple zone at the base of the building, and the huge build-up of pressure forcing the material upwards through shafts (or new cavities emerging during collapse) and being forced out as the material progressively shoots upwards. Alternatively the ‘squibs’ are merely damaged panels flapping about, perhaps moving due to pneumatic pressures from pancaking.



The supposed existence of ‘squibs’ in the Twin Towers is also cited as evidence for the CD theory, but, as Debunking 911points out on its squib page, the ejecta generally increase in intensity over time, as one would expect from pneumatic effects. Explosives are defined by the fact of the incredibly short time in which their blast wave spreads, quite unlike the spurts in the Twin Tower videos.



Returning to WTC 7, Popular Mechanics interviewed a NIST official and reported as follows:



NIST's Sunder tells PM. "On about a third of the face to the center and to the bottom--approximately 10 stories--about 25 percent of the depth of the building was scooped out." NIST also discovered previously undocumented damage to WTC 7's upper stories and its southwest corner.



NIST investigators believe a combination of intense fire and severe structural damage contributed to the collapse, though assigning the exact proportion requires more research. But NIST's analysis suggests the fall of WTC 7 was an example of "progressive collapse," a process in which the failure of parts of a structure ultimately creates strains that cause the entire building to come down. Videos of the fall of WTC 7 show cracks, or "kinks," in the building's facade just before the two penthouses disappeared into the structure, one after the other. The entire building fell in on itself, with the slumping east side of the structure pulling down the west side in a diagonal collapse.



According to NIST, there was one primary reason for the building's failure: In an unusual design, the columns near the visible kinks were carrying exceptionally large loads, roughly 2000 sq. ft. of floor area for each floor. "What our preliminary analysis has shown is that if you take out just one column on one of the lower floors," Sunder notes, "it could cause a vertical progression of collapse so that the entire section comes down."



There are two other possible contributing factors still under investigation: First, trusses on the fifth and seventh floors were designed to transfer loads from one set of columns to another. With columns on the south face apparently damaged, high stresses would likely have been communicated to columns on the building's other faces, thereby exceeding their load-bearing capacities.



Second, a fifth-floor fire burned for up to 7 hours. "There was no firefighting in WTC 7," Sunder says. Investigators believe the fire was fed by tanks of diesel fuel that many tenants used to run emergency generators. Most tanks throughout the building were fairly small, but a generator on the fifth floor was connected to a large tank in the basement via a pressurized line. Says Sunder: "Our current working hypothesis is that this pressurized line was supplying fuel [to the fire] for a long period of time."



This text is available at: Debunking the 9/11 Myths: Special Report - Popular Mechanics. Note that we are, as of August 2006, still awaiting the NIST report on WTC 7: it may well throw up new data.

Brent Blanchard devotes section 3 of his paper to refuting the claim that plumes indicate explosives, pointing out that it is air-expulsion that causes the visible sitings of plumes etc.


2.6 Early Drop of North Tower Antenna



I am particularly puzzled why Jones thinks that the ‘early’ drop of the North Tower antenna points to controlled demolition:



Jones: “The building stood for more than an hour and a half. Videos of the north tower's collapse appear to show that its television antenna began to drop a fraction of a second before the rest of the building. The observations suggest that the building's steel core somehow gave way first… (Glanz and Lipton, 2002; emphasis added)

But how? What caused the 47 enormous steel core columns of this building which supported the antenna to evidently give way nearly simultaneously, if not cutter charges?”



Jones commits, not so much an error of science here, as an error in logic. The IF theory requires the ‘47 enormous steel core columns’ of the building to give way first, due to structural damage and fire. The CD theory requires that cutter charges do the job. But the early drop of the North Tower antenna is consistent with either theory. Therefore Jones cannot claim that this phenomenon supports only the CD theory. It is also not clear why he wants to call it an ‘anomaly’ other than perhaps to discredit the IF theory by stealth.



When records from east and west vantage points were viewed, it was apparent that the building section above the impact area tilted to the south as the building collapsed. (NIST, 2005)



Jones: However, we find no quantitative analysis in the report which shows that this tilting of the building section was sufficient to account for the large apparent drop of the antenna as seen from the north, or that this building-section-tilting occurred before the apparent antenna drop. Furthermore, the FEMA investigators also reviewed "videotape recordings of the collapse taken from various angles" yet came to the sense that "collapse began with one or more failures in the central core area of the building." (FEMA, 2002) Quantitative analysis needs to be done and shown to resolve the issue.



All that Jones is doing in this statement is to re-iterate the challenge to the IF theory to account for the collapse of the central columns. The early descent of the antenna lends no additional support to the CD theory whatsoever, though at the same time it does not contradict it. Put more simply: it is a red herring.


2.7 Eyewitness Accounts of Flashes and Loud Explosions



The CD theorists draw a lot on eyewitness testimony from non-experts.



Jones: ‘Multiple loud explosions in rapid sequence were heard and reported by numerous observers in and near the WTC Towers, consistent with explosive demolition. Firemen and others described flashes and explosions in upper floors near where the plane entered, and in lower floors of WTC 2 just prior to its collapse, far below the region where the plane had struck the tower (Dwyer, 2005). For instance, at the start of the collapse of the South Tower a Fox News anchor reported: “There is an explosion at the base of the building… white smoke from the bottom… something happened at the base of the building! Then another explosion.” (De Grand Pre, 2002, emphasis added.)’



When Jones says that ‘explosions’ were heard, he is, like with the word ‘squib,’ using language that implies a pre-judgement. A more neutral and scientific term would be ‘loud report’ possibly consistent with explosions. To say that these reports were ‘multiple loud explosions consistent with explosive demolition’ (my italics) is to further lead the reader. But has Jones taken the trouble to play the interviewees audio tapes of controlled demolition to see how closely the reports resemble the detonation of typical explosives used in demolition? Such explosives detonate with a signature ‘crack’ quite different to the loud reports that can be generated from a host of other phenomenon. Aviation fuel, spilling through the building and building up pockets of fuel-air mixtures in confined spaces, would detonate as a stray spark reached them from the fires above. It is known that floors collapsed prior to the main descent of the buildings: the sounds of steel buckling and breaking, and of concrete smashing onto lower floors, would all emit loud reports. Many other objects and devices commonly found in skyscrapers would explode when exposed to fires of up to an hour and a half: has Jones made any study of this in connection with conventional fires?



The issue of loud reports issuing from ground or lower floors is in fact inconsistent with the CD theory. This is because the building collapsed from the top, not the bottom, and hence the CD theory itself would rule out the placing of charges at the lower floors. The CD theory of the twin towers collapse has to be a theory of top-down demolition. This is recognised by 911 Review (which promotes the CD theory) in a webpage called “DISTRACTION: 'Explosions in the Towers' Basements Preceded Collapses'” The pages states:



The idea that powerful explosions in the Towers' basements initiated the collapses is not supported by credible evidence, but is contradicted by large bodies of evidence. We note:



· The conclusions that seismic spikes preceded the collapses is based on flawed analysis.

· The body photographic and video evidence contradicts the idea that large explosions in the Towers' bases precipitated the collapses.

· The testimonies of emergency responders do not include descriptions of large-scale explosions low in the towers preceding the descent of the dust clouds. (9-11 Review: DISTRACTION: 'Explosions in the Towers' Basements Preceded Collapses')



Brent Blanchard devotes section 4 of his paper to refuting the claim that eye-witness heard the sound of explosives. He says: 'Simply put, there are countless causes of sharp, loud noices that have no relation to explosives. The only scientifically legitimate way to ascertain if explosives were used is to cross reference the fundamental characteristics of an explosive detonation with independed ground vibration data recorded near Ground Zero on 9/11.' I’ll return to the issue of seismic spikes, and why these eliminate the possibility of explosives, in section 3.3.


2.8 Ejection of Steel Beams and Debris-plumes from the Towers



Jones: “The horizontal ejection of structural steel members for hundreds of feet and the pulverization of concrete to flour-like powder, observed clearly in the collapses of the WTC towers, provide further evidence for the use of explosives – as well-explained in Twin Towers Demolition. (See also, Griffin, 2004, chapter 2.) The observed plumes or "squibs" are far below the pulverization region and therefore deserving of particular attention. They appear much like the plumes observed in ImplosionWorld.com (e.g., the controlled demolition of the Southwark Towers).”



The CD hypothesis is somewhat self-contradictory here, in that much is made of the collapse of the towers into a small area as evidence of ‘skilled’ controlled demolition. On the other hand the ‘horizontal ejection of steel members’ which spread the debris well beyond the footprint of the building is also cited as evidence of CD. But careful observation of controlled demolition shows that much material is ejected horizontally at the point of pancaking, i.e. in the crumple zone. This ejection is not caused by explosion but by the huge pneumatic overpressures of the descending building. The Towers, unusually, had a crumple zone very high up, making the horizontal ejection of material uniquely visible. While explosives could have caused this, so could the pneumatic pressure of descent of the upper floors. In WTC 1 there were between 12 and 18 stories collapsing onto the impact area between floors 94 and 98, while in WTC 2 there were between 26 and 32 stories collapsing onto the impact area between floors 78 and 84. If one views the base of a 12-18 story building or a 26-32 story building being demolition in a traditional bottom-up demolition, vast amounts of debris are ejected at this point. (To put it in perspective the tallest building ever demolished by controlled explosions is 25 storeys.)



The issue of pulverisation is also crucially misunderstood. By far of the bulk of pulverisation that takes places in a controlled demolition is not due to explosives, but due to the free-fall descent of the building.



The plumes referred to by Jones (called ‘mysterious’ in the caption he provides next to the photo illustrating them) could be caused by explosives. Equally the enormous pneumatic overpressures caused by the collapse above them (involving a greater mass at this point in the descent than in any controlled demolition in history) could easily have forced material ahead of them to blow out of any weakest route made possible by the combination of vertical shafts and horizontal corridors.



All of the observed phenomenon, as Jones points out, could be the result of explosions. But equally, all of them are consistent with gravity-powered collapse, once begun. It is also important to note that much of the dust produced would have been from plaster, a material that disintegrates far easier than concrete. The NIST findings confirm that gypsum (the main ingredient of plaster) was widely found in the debris.


2.9 Rapid Collapses and Conservation of Momentum and Energy



Jones: “How do the upper floors fall so quickly, then, and still conserve momentum and energy in the collapsing buildings? The contradiction is ignored by FEMA, NIST and 9-11 Commission reports where conservation of energy and momentum and the fall-times were not analyzed. The paradox is easily resolved by the explosive demolition hypothesis, whereby explosives quickly remove lower-floor material including steel support columns and allow near free-fall-speed collapses (Harris, 2000).”



To many people the apparent collapse of the buildings at ‘near free-fall-speed’ is one of the most compelling arguments in favour of the CD theory. However it is also the most easily dealt with on scientific grounds. The fact is that the near free-fall-speed of collapse of buildings in controlled demolition is entirely due to gravity, and not to explosives. The question of course remains, how come that buildings, impeded by their intact lower floors, collapse so fast? (Though of course, this is not a question with any direct relevance to 9/11.) Put this way, the question conveys the essential fact of controlled demolition: that the only floors effectively ‘removed’ from the building are the lowest. (Further charges are placed in the building if and only if it is necessary to guide its fall in a certain way, for example to collapse a building into its footprint.) In a 20-story building, for example, the bottom floor or floors is extensively rigged with explosive, to remove its load-bearing capability. The remaining 18-odd storeys pancake into the region of the destroyed floor, one at a time, raising exactly the same question as to how is it that this process can take place so quickly? The same question applies to conventional demolition, and to the Tower buildings. The difference is that the pancaking occurs high in the Twin Towers (‘top-down pancaking’), and at the base of WTC 7 (‘bottom-up pancaking’). In the usual bottom-up process each floor impedes the process of collapse through its structural rigidity, just as much as one would expect in the top-down processes in the Towers. Although no text-book account is available which might give a simple answer to the issue of the speed of gravitational collapse of buildings, one might draw on the analogy of a hydraulic press compressing, say, a car body shell. The car body shell may seem strong enough to withstand everyday loadings, but, when it takes the hit of a high-powered press, it collapses with astonishing speed. 18 storeys of a big building, moving even rather sedately as they would at the onset of collapse, probably outstrip the forces of even the biggest hydraulic press ever built.



It seems that all the proponents of the CD theory state the case, like Jones above, along the lines: “The paradox is easily resolved by the explosive demolition hypothesis, whereby explosives quickly remove lower-floor material including steel support columns and allow near free-fall-speed collapses.” This is simply unscientific; not corresponding to the reality of how controlled demolition is carried out. Returning to our example of the collapse of a 20-story building, there is simply no need to explode each floor, and such explosions are certainly not the explanation of why buildings fall so fast in controlled demolition. All the calculations produced by the CD theorists, designed to prove their theory, are based on the wrong premise, that explosions accelerate the descent. They don’t: it is purely gravity that does it.



Jones: “We observe that approximately 30 upper floors begin to rotate as a block, to the south and east. They begin to topple over, not fall straight down. The torque due to gravity on this block is enormous, as is its angular momentum. But then – and this I’m still puzzling over – this block turned mostly to powder in mid-air! How can we understand this strange behavior, without explosives?”



Jones seems to believe that a 30-story section of the building was “turned mostly to powder in mid-air,” through the use of explosives. He ignores the fact that large sections of the building, such as this, did fall, and were responsible for destroying or partly destroying other WTC buildings. Although considerable disintegration of the 30-story block was inevitable as it impacted on the rest of the South Tower, the bulk of the pulverisation would have been on impact on the WTC complex. Here is a photo of a large chunk of WTC 2 falling onto WTC 3, which was almost totally destroyed by debris falling from the Towers. This fragment shows a different orientation to the section described by Jones, which suggests that angular momentum was conserved.







The next photo shows the destruction wreaked on WTC 3 by debris falling from WTC 2.





This photo was taken after the collapse of WTC2 and before the collapse of WTC1, half an hour later. It must surely lay to rest the idea that the Towers were blasted to bits in mid-air. Only large chunks of falling debris, as shown in the previous photo, could cause this kind of destruction.



But anyway, to truly explode a 30 story building in mid-air would be an astonishing feat of pyrotechnics, and would also beg the question: why bother? But if Jones is serious, the estimate of the amount of explosives required, in metric tonnes, would be staggering, plus the almost insurmountable feat of triggering them at this point in the collapse. Jones, in section 1, estimates “Roughly 2,000 pounds of RDX-grade linear-shaped charges” would be sufficient to bring the building down (note: around one metric tonne). He says: “The estimate is based on the amount of explosives used in controlled demolitions in the past and the size of the buildings.” He doesn’t point out however that this quantity of explosives merely cuts the building up for descent, and that it is gravity that does the work of pulverising. The amount of RDX would go up by factors of hundreds to achieve what Jones imagines for the top 30 storeys, and of course is multiplied again if the CD theory demands that explosives account for all the pulverisation. Even if hundreds or thousands of tonnes of RDX could be insinuated into the building without anyone noticing, the question again would be: what on earth for?



It is worth showing some pictures here that show how parts of the North Tower took much longer than free-fall speeds to collapse:







This shard or ‘spire’ of the North Tower remained standing some 15s after the main collapse


In this photo it begins to collapse


In this photo vertical columns can be seen breaking away, demonstrating how, once collapse began, the steel columns peeled away from the structure.



The Debunking 911 site devotes a page to demonstrating that the buildings did not fall at free-fall speeds, and is worth looking at: Debunking 9/11 Conspiracy Theories and Controlled Demolition - Free Fall.


2.10 Controlled Demolition “Implosions” Require Skill



The photos above show that Jones is exaggerating ‘straight-down and complete collapses’:



Jones: “The occurrence of nearly symmetrical, straight-down and complete collapses of the WTC 7 and the Towers is particularly upsetting to the “official” theory that random fires plus damage caused all these collapses. Even with high-level cutting charges, achieving such results requires a great deal of pre-planning and expertise.”



This image sequence should destroy the myth that the Towers collapsed symmetrically or straight-down:







1


2


3





4


5


6



In frame 2 of the video sequence we can see a large chunk of WTC 2 falling down to its left. In frame 3 a much larger part of the building, most likely the 30-story section above the impact zone, clearly rotating away from the building, reaching – I would estimate – something like one-third of the Tower height away from the Tower. In the video it is clearly visible rotating away from the building, fully conserving its angular momentum. One has to ask why Jones ignores clear evidence like this, going back to the claims he makes in the previous section that this large chunk turned to powder in mid air. From the video it is clear that this section of the building is rotating as a relatively intact unit until we can no longer see its further progress, due to the dust cloud.



Jones is highlighting a common perception, that the “nearly symmetrical, straight-down and complete collapses of the WTC 7 and the Towers” is the strongest evidence for controlled demolition. The Twin Towers present a very different case to the WTC 7 building, and their collapse is the most indelibly printed on the public imagination. However, they are most easily dealt with. Their collapse is like no controlled demolition ever carried out in the world. This is because they collapsed in a top-down fashion. Jones inadvertently confirms this when he quotes Harris: “Generally speaking, blasters will explode the major support columns on the lower floors first and then a few upper stories,” and Mark Loizeaux, president of Controlled Demolition, Inc: “If I were to bring the towers down, I would put explosives in the basement to get the weight of the building to help collapse the structure.” But it is absolutely clear from the way that the twin towers collapsed that there was no collapse from the lower floors or basement of the building: collapse began at the impacted floors and proceeded top-down.



Jones makes no acknowledgement of this fact, confusing the issue further by stating:



“Just right – “explosives in the basement” agrees with eyewitness reports of pre-collapse explosions down low in the buildings (point 7 above). Also, this would be the way to effectively sever the support columns, consistent with both the apparent initial drop of the communication tower (WTC Tower 1) and the “kink” in the middle of WTC 7 as its collapse began.”



This is patently absurd. Jones imagines that explosive detonations were carried out low in the Tower buildings, severing the support columns, which then somehow ‘slid’ through the building while the outer structure remained in place, but achieving the initial drop of the North Tower antenna. He imagines that severed columns in the base of the building would somehow cause a collapse at floors 80 to 90 with no movement of the building in between. Any examination of the videos of collapse in conventional demolition show that once the lower columns are severed, collapse begins at the bottom of the building.



The fact is that the Twin Towers began their collapse at the levels where the planes impacted, and that the unique top-down collapse, never seen before in the entire history of the demolition of tall buildings, ensured that they fell (very) approximately within their footprint, rather than toppling. In fact the spread of debris was far greater than would be acceptable in any implosion, but then, no building of this height has ever been demolished by explosives (a building like this would be dismantled). If Jones requires a controlled demolition theory, then the explosives would have to have severed columns at the level of aeroplane impact, not at the ground level.



The WTC 7 building is a different case, which does resemble controlled demolition, in some aspects only, in particular that it follows a conventional bottom-up collapse. But the CD theory never recognises the following facts:



1. No building ever suffered both impact damage and fire on the scale of WTC 7, allowing unimpeded air supply not possible to fires in the absence of structural damage

2. No building ever burned for 7 hours with such a complete absence of fire-abatement effort, made impossible by the severing of water mains, and the extraordinary demands on the city’s fire department.



The initial ‘kink’ that Jones refers to is consistent with a localised collapse in the front centre of the building, consistent with the structural damage to the front of the building and the huge supply of air available.


2.11 Steel Column Temperatures of 800°C Needed: A Problem in the Argument of Bazant and Zhou



Jones: “Correct – the WTC Towers were designed to withstand forces caused by large commercial aircraft – we can agree on that. MIT’s Thomas Eagar also concurs “because the number of columns lost on the initial impact was not large and the loads were shifted to remaining columns in this highly redundant structure” (Eagar and Musso, 2001).”



Jones is stating here a widely circulated opinion: that the Towers were designed to withstand the impact of a commercial plane. But the CD theorists consistently overlook two factors here. Firstly that the designers had in mind an aircraft coming in to land at New York airport, at speeds of around 180 mph (according to the FEMA report, page 1:17). But the aircraft hit the towers at an average of nearly three times that speed. Given that the impact damage hinges on the kinetic energy of the projectile, which rises with the square of speed, the planes hit the Twin Towers with nearly nine times the impact anticipated. (Note that the NIST report - on page 6 - contradicts this argument by stating that the Towers were designed for a 600 mph impact. I would be pleased to hear from anyone who can settle this discrepancy one way or the other.) Secondly, design is an art not a science: the Titanic was designed not to sink; the space shuttle was designed not to explode on takeoff, and designed not to break up on re-entry. Etc.



Jones: “They do NOT explain how steel-column temperatures above 800oC were achieved near-simultaneously due to burning office materials. NIST notes that office materials in an area burn for about 15-20 minutes, then are consumed away (NIST, 2005, pp. 117, 179). This is evidently not long enough to raise steel column temperatures above 800oC as required in the Bazant & Zhou model, given the enormous heat sinks of the structures. And to have three buildings completely collapse due to this unlikely mechanism on the same day strains credulity.”



Jones is presenting perhaps the core issue that requires explanation: the high temperatures in all three fires. What the CD theorists consistently attempt to promote however is that the fires in the three buildings were standard ‘office fires’ which should not have led to collapse. This is simply not the case.



In the case of the Twin Towers the impact and presence of the planes ensures that the structural damage and ensuing fires were like nothing previously encountered. Some images are essential here to convey the magnitude of the situation.







These diagrams require that any serious thinker on this subject consider the impact of the planes: AA flight 11 crashed into north face of North tower (WTC1), between floors 94 and 98, at 470 mph, and UA 175 crashes into south face of the South Tower (WCT2), between floors 78 and 84, at 590 mph. One CD theorist compared these impacts to a ‘pencil going through a mosquito net,’ part, it seems, of a consistent attempt to downplay their importance. Here is a visualisation of the impact on WTC2:















Fig. 3 Frames from a visualisation of WTC2 impact (source: Debunking 911 Conpiracy Theories and Controlled Demolition Homepage)



As the FEMA report points out, UA 175 crashed into the WCT2 in a direction to make its passage towards the central core of the building much shorter. Here is a visualisation of the impact damage:





Fig. 4 Visualisation of impact damage on WCT 2 (source: Debunking 911 Conpiracy Theories and Controlled Demolition Homepage)



While no-one can verify the details of such a visualisation, it would be at the very least likely that a significant number of core columns would have been damaged by the impact alone, prior to any weakening by fire.



A passenger jet can crash and initiate intense fires, even, apparently, without its aviation fuel igniting, as in this example of an Air France accident:









Fig. 5 Air France Airbus 340 flight 358 crash (source: Debunking 911 Conpiracy Theories and Controlled Demolition Homepage, see also Air France Flight 358 - Wikipedia, the free encyclopedia)



One can see that the wings of the aircraft, where the fuel is kept, did not catch fire. The intense blaze and utter devastation of the fuselage was due only to friction on impact and combustibles within the fuselage. Notice the intense yellow-orange base of the fire behind the wing in the first picture: easily hot enough to melt aluminium at 650 degrees centigrade. If one now imagines this crash compressed into the impact zones in the Towers, plus around 10,000 gallons each of aviation fuel, then how can one conceive of the resulting conflagration as a mere ‘office fire?’



Returning to the impact of the planes, one can calculate their kinetic energy at the time of impact to be about 4.415 x 1009 Joules (equivalent 4 million one bar electric fires operating for one second). This energy alone is capable of melting four metric tonnes of steel, though of course no one would suggest that the kinetic energy of a plane would be converted 100% into heat and focussed on the steel. The energy would appear as a mixture of fracture energy, sound energy, heat energy and even a small amount of light. But the point seems to be lost on the CD theorists: that impact energy was substantial, and that a significant proportion would be converted to heat energy, never mind the combustibles on the plane and the aviation fuel.



To put it another way: how can one ignore 150 metric tonnes of aircraft impacting at speeds between 470 and 590 mph, when skidding off a runway at perhaps only 100 mph caused a complete conflagration in Air France 385? And when it received prompt attention from the airport fire brigade? (They were hampered by heavy rain which diluted the millions of gallons of foam deployed on the blaze, and it took 12 hours to put out.)



This is another key issue that the CD theorists ignore: the lack of fire abatement provision that would be normal in a conventional ‘office fire.’ The 9/11 Commission Report details the decision made early in the events that the fire department response would be rescue only and not fire fighting (p. 290-291). This decision was made on the grounds of the magnitude of the emergency at that point, and the imperative to rescue thousands of office workers. Also clear is that the fire department had no idea whether any water supply was still functional.



Summary

In the 17-minute period between 8:46 and 9:03 A.M. on September 11, New York City and the Port Authority of New York and New Jersey had mobilized the largest rescue operation in the city's history. Well over a thousand first responders had been deployed, an evacuation had begun, and the critical decision that the fire could not be fought had been made. (CR p.293, my italics)



This is a good point to raise a pet theory of mine (and it is only a theory): that the many tons of aluminium in the planes may have contributed to the fire and the high temperatures, by igniting. Normally, aluminium does not burn in air, due to the very tough layer of oxide that rapidly forms on its surface. However the Air France jet would have involved abnormal conditions in which the aluminium was effectively ground against concrete at 100 mph, bearing the weight of the plane. The friction involved was enormous, and sufficient to bring the plane to rest, and may have provided, along with an 100 mph oxygen supply, the conditions for the aluminium to burn. The impact conditions of the planes entering the Twin Towers was likewise far from normal, and even if only a few tons of the aluminium burned, it would have produced very high temperatures indeed and a large heat input to the conflagration. It will be interesting to see, when the Air France crash report is produced, whether it shows (a) that indeed little or no aviation fuel contributed to the fire, and (b) whether the aluminium of the hull burned rather than just melted.


2.12 Problems in the NIST Report: Inadequate Steel Temperatures and Tweaked Models



Jones: “However, I along with others challenge NIST’s collapse theory. NIST maintains that all three building collapses were fire-initiated despite the observations above, particularly the fact that fire endurance tests with actual models did not result in collapse. … I agree with these pointed objections, particularly that the “response of the whole frame” of each building should be considered, especially heat transport to the whole frame from localized fires, and that the “core columns cannot pull the exterior columns in via the floor.” (Lane and Lamont, 2005)”



From a scientific point of view these are some of the most difficult issues to deal with, but Jones misrepresents NIST here when he says “NIST maintains that all three building collapses were fire-initiated.” NIST is careful to point out that the collapse resulted from three factors, not the single factor of fire. The two additional factors, apart from fire were (1) structural damage due to impact, and (b) the damage to insulation caused by the impact. NIST say: “In the absence of structural and insulation damage, a conventional fire substantially similar to or less intense than the fires encountered on September 11, 2001, likely would not have led to the collapse of a WTC tower.” (NIST NCSTAR 1, p. 176) Jones may be right when he says that heat transport away from the fire zone may not have been considered, but the fact is that the conductivity of steel is not that good (as he points out himself elsewhere in his paper), and localised heating is very easy. One only has to look at a workman cutting through steel with an oxyacetylene torch to realise that heat transport away from the cutting area is poor.



Jones “The computerized models of the Towers in the NIST study, which incorporate many features of the buildings and the fires on 9-11-01, are less than convincing. … The NIST report makes for interesting reading. The less severe cases based on empirical data were discarded because they did not result in building collapse. But ‘one must save the hypothesis,’ so more severe cases were tried and the simulations tweaked, as we read in the NIST report: …”



Jones has an important point here, that computerised models, along with all the diagrams, sketches and visualisations presented in the official reports (and elsewhere), are open to challenge. But the term ‘tweaking’ is a rather leading one (though not as leading as the term ‘revisionist’ that Griffin uses). The point of adjusting the model’s parameters until the model shows collapse is to arrive at parameters consistent with the hypothesis. The parameters themselves are then open to scrutiny. As NIST says, quoted by Jones: “To the extent that the simulations deviated from the photographic evidence or eyewitness reports [e.g., complete collapse occurred], the investigators adjusted the input, but only within the range of physical reality. Thus, for instance,…the pulling forces on the perimeter columns by the sagging floors were adjusted... ” NIST is saying that the parameters are “within the range of physical reality,” so it is up to Jones to demonstrate that they are not, in which case the NIST hypothesis would look weak. But instead Jones mocks the modelling process itself by saying “How fun (perhaps) to tweak the model like that, until the building collapses -- until one gets the desired result.” This misrepresents the purpose of the modelling, which in reality is to arrive at parameters then open to scrutiny. But Jones merely puts forward some opinion regarding other fire models which failed to predict collapse, without any mention of whether those models included the two additional factors that are core to the NIST hypothesis: structural damage, and insulation damage.



Jones: “So how does the NIST team justify the WTC collapses, when actual models fail to collapse and there are zero examples of fire-caused high-rise collapses? Easy, NIST concocted computer-generated hypotheticals for very “severe” cases, called cases B and D (NIST, 2005, pp. 124-138). Of course, the details are rather hidden to us. And they omit consideration of the complete, rapid and symmetrical nature of the collapses.”



Jones persists here in ignoring what NIST are saying: that their models do predict collapse for a certain range of parameters (within the range of physical reality), and that the collapse was not due to fire alone, but due to fire + structural damage + insulation damage. It is true that NIST chose not to consider the dynamics of the structures once collapse was initiated, but they had no particular reason to do so.



Jones concludes this section by saying:



“What about the subsequent complete, rapid and symmetrical collapse of the buildings? What about the observed squibs? What about the antenna dropping first in the North Tower? What about the molten metal observed in the basement areas in large pools in both Towers and WTC 7 as well? Never mind all that: NIST did not discuss at all any data after the buildings were “poised for collapse.” Well, some of us want to look at ALL the data, without "black-box" computer simulations that are “adjusted,” perhaps to make them fit the desired outcome. An hypothesis which is non-refutable is non-scientific. On the other hand, Occam's razor suggests that the simplest explanation which addresses and satisfies ALL the evidence is most probably correct.”



In this paper we meet all of Jones’s objections made here. If Jones wants to really put forward a hypothesis that satisfies all the evidence, then that hypothesis (controlled demolition) needs to be spelled out in some detail to see if it can withstand the kind of scrutiny that the impact / fire hypothesis has been exposed to.


2.13 NIST's Failure to Show Visualizations



Jones may have a valid criticism here, but equally he may not. To ‘show’ visualisations is precisely what NIST have done in their report, by including numerous diagrams generated by the modelling software. Perhaps Jones would like access to the software itself plus the final database and its variants, in order to better understand the model. But I don’t know how common it is to make copies of proprietary software and datasets available on request. Certainly it is difficult, without substantial resources, to obtain such software, and to construct the datasets necessary for such visualisations. But the onus is on Jones, if he wants to show the validity of the CD theory, to attempt at least a basic model of the proposed demolition sequence, and to test it on available software.


2.14 Jones’s Summary



Jones concludes his case with this summary:



Jones: “Remarkably, the controlled demolition hypothesis accounts for all the available data rather easily. The core columns on lower floors are cut using explosives/incendiaries, near-simultaneously, along with cutting charges detonated up higher so that gravity acting on now-unsupported floors helps bring down the buildings quickly. The collapses are thus near-symmetrical, rapid and complete, with accompanying squibs -- really very standard stuff for demolition experts. Thermate (whose end product is molten iron) used on some of the steel columns readily accounts for the molten metal which then pooled beneath the rubble piles as well as the sulfidation observed in steel from both the WTC 7 and Towers rubble piles (points 1 and 2 above).



I believe this is a straightforward hypothesis, much more probable actually than the official hypothesis. It deserves scientific scrutiny, beyond that which I have been able to outline in this treatise.”



I have shown that the controlled demolition hypothesis does not account for the available data at all, and that this summary by Jones is absurd. If the core columns on lower floors had been cut, then the building would have been observed to have collapsed starting from that point, pancaking into the lower floors. It did not. If the speed of descent required cutting charges detonated higher up, then other buildings falling at the same speed would do so because of such charges. They do not. If the observed ‘squibs’ were due to controlled demolition, they would have just appeared prior to collapse, and would not involved prolonged expulsion of material. They did not. Thermate is just not ‘standard stuff’ for demolition experts: they never use it because its timings are uncontrollable, and its combustion products cannot cut steel columns. It is simply bad science for Jones to say: ‘The core columns on lower floors are cut using explosives/incendiaries, near-simultaneously’ (my italics) because the slow action of an incendiary like thermite makes any attempt at precise timings impossible.



Molten metal beneath the rubble may have a number of causes, the most likely of which is the mgh energy of the building. If only 0.1 % of its collapse energy (one thousandth) were converted to heat, then that would be sufficient to melt a metric tonne of steel.



In another of Jones’s concluding remarks he says: “The controlled-demolition hypothesis cannot be dismissed as "junk science" because it better satisfies tests of repeatability and parsimony. It ought to be seriously (scientifically) investigated and debated.” [my italics]



It is precisely because the events of 9/11 are not repeatable that makes the science around its investigation difficult. In real scientific terms the different hypotheses would have to be tested by flying similar aircraft into similar buildings: clearly impossible. But Jones’s appeal to ‘parsimony’ is instructive: it seems that he would like a simple explanation of the events instead of the complex impact-plus-fire-plus-insulation-damage ‘official’ hypothesis. We show here that controlled demolition is far from the parsimonious account that he believes, because when examined seriously it generates far more problems than it solves.

I will conclude this section with a brief summary of the argument put forward by Brent Blanchard against explosive demolition. As Blanchard is an expert on this topic, it is up Jones to defeat his simple but powerful points: (1) that the impact and subsequent fires would have set off or destroyed any pre-planted explosives, (2) that it would have been impossible for a team to plant the explosives between impact and collapse in the case where such explosives were not pre-planted, and (3) that seismic recordings show none of the tell-tale signatures of explosives leading up to the collapse of any of the buildings. I'll return to point 3 in section 3.3.


3 Additional Arguments for the CD Hypothesis



Jones in his online paper does not rehearse all the arguments put forward by CD theorists, so for completeness I list and address them here.



1. Timing of Tower collapses in reverse order of impact

2. Energy required to pulverise concrete and produce dust clouds greater than potential energy of buildings

3. Seismic recordings made by Columbia University consistent with controlled detonations

4. Sudden onset of collapse consistent with demolition

5. Core columns should have remained standing

6. Explosions in the sub-basement



There are of course many more, but some cut-off is required, as even the CD theorists point out. They call the more outlandish suggestions, e.g. that the Towers were brought down by missiles, a ‘poisoning of the well,’ perhaps suggesting even that there is a conspiracy to discredit the CD theory with totally implausible ideas. We are attempting to show however that even any sober variant of the CD theory faces difficulties far greater than the IF theory.


3.1 Timing of Tower collapses



Griffin cites a theory by Meyer that suggests that the fire in the South Tower had less fuel than in the North Tower and therefore went out earlier, despite having been initiated later. Those controlling the demolition (in this imagined scenario) were then forced to detonate their cutter-explosives at that point to bring the building down, and then waited until the fire in the North Tower went out until they brought that down. (NPH, p.18) But Griffin fails to put forward the NIST hypothesis, stated in Finding 58 (NIST NCSTAR 1-6, p.338):



“The time it took for each WTC tower to collapse was due primarily to the difference in structural damage, the time it took the fires to travel from the impact area across the floors and core to critical locations, and the time it took to weaken the core and exterior columns. WTC 2 had asymmetric structural damage to the core, including the severing of a corner core column, and WTC 1 had more symmetrical damage. The fires in WTC 2 reached the east side of the building more quickly, within 10 min to 20 min, than the 50 to 60 min it took the fires in WTC 1 to reach the south side.”



It is worth clarifying this a little: the difference in structural damage, and hence the subsequent sequence of events, was due to two factors: the much faster speed of the plane that hit WTC 2 compared to the plane that hit WTC 1, and the orientation of the plane to WTC 2, which meant that it (a) created a more asymmetrical impact zone, as confirmed in the tilting of the entire structure above, and (b) had a much shorter distance to travel in order to impact on the core structure of the building.



We note also that Mark Loizeaux had instinctively predicted that WTC 2 would collapse earlier, because it was hit lower down. His implication, clearly, is that the extra weight on the impact zone would cause structural supports to give way more quickly.


3.2 Energy Required to Pulverise Concrete



The CD theorists are drawing on two factors in arguing that the pulverisation of the concrete in the Towers could not have been the product of gravitational collapse. The first argument is intuitive: it just seems improbable, judging from the photos and videos of the early stage of collapse, especially before the collapse has reached any speed. The second factor is a calculation made by Jim Hoffman, and widely cited.



Before looking more closely at the calculations, I can point out again that it is a knowledge of demolition that provides the evidence here against the CD theory. Quite simply, in controlled demolition, the proportion of pulverisation accounted for by the explosives is negligible. To state again the first principle of explosive demolition: explosives initiate the collapse, gravity does the rest.



In Hoffman’s calculations on the energy required to produce the dust cloud he starts with an estimate of the dust cloud volumes from this photograph:





He proceeds to make estimates of the volume of this cloud, and the expansion of it as an entity, starting from the volume of the towers. Along the way, he has to make numerous other estimates, including the average particle size of the cloud and so on. He claims at each stage to make a conservative estimate, and concludes his calculations thus:



‘The amount of energy required to expand the North Tower's dust cloud was many times the entire potential energy of the tower's elevated mass due to gravity. The over 10-fold disparity between the most conservative estimate and the gravitational energy is not easily dismissed as reflecting uncertainties in quantitative assessments.’



This assessment that the dust cloud alone required ten times the North Tower’s gravitational energy (mgh energy) to produce is widely cited by the CD theorists, including Griffin, and is of course startling. But they do not point out that the mgh energy of the North Tower is alone equivalent to about 270 tonnes of high-explosive TNT, and for both towers together 540 tonnes. If Hoffman’s calculations are to be taken seriously, this requires a total of 5,400 tonnes of TNT or equivalent explosives, less the 540 mgh equivalent. Hoffman’s calculations would therefore require nearly 5,000 tonnes of high explosive to be packed into the two towers (5 kilotonnes of TNT equivalent). By way of comparison, the nuclear bomb dropped on Hiroshima is estimated at between 12 and 14 kilotonnes of TNT equivalent. Can Hoffman be serious?



As of August 2006, even Hoffman doesn’t seem to be serious, as he has now reached version four of his analysis, which is supposed to replace his previous versions, but which he chooses not to place on the internet (version four is at: The North Tower's Dust Cloud and has withdrawn all his estimates and calculations). There is no indication that his research has been submitted for publication and hence peer review by scientists competent to assess his estimates and calculations. All we can do at this stage is point out that his claim of the ten-fold disparity in energy requirements, as a conservative disparity, would require the conspirators to hide of the order of five thousand tonnes of TNT equivalent in the Twin Towers, an equivalent of more than a third of the Hiroshima bomb. It is more likely however that his train of assumptions is faulty, perhaps even his starting point in attempting to model the immense complexity of the dust cloud as the expansion of a discrete volume of gas.



As to the energy required to pulverise the rubble, the calculations are uniquely dependent on two estimates: the average size of the particles, and the strength of the material. The CD theorists rely on only the most general of guesses as to the first figure, and insist on using only the strength of concrete in their calculations. Given that a significant proportion of the dust would have been generated from plaster, with a much lower strength, their estimates must be regarded as unreliable. Technically, the production of rubble or powder from rock or aggregate is known as comminution, and the energy required depends on what is known as the Bond work index: this is highest for rock, less for concrete, and much smaller for plaster.


3.3 Seismic Recordings



Many CD theorists draw attention to seismic recordings as evidence of the CD theory. Griffin (for example), drawing on Hufschmid, cites seismic data from Columbia University to support the CD theory:



‘In each case, “the shocks increased during the first 5 seconds then dropped abruptly to a lower level for about 3 seconds, and then slowly tapered off.” This pattern, Hufschmid suggests, reflects the fact that the first explosives detonated were those near the tops of the towers, where the steel columns were the thinnest. The shocks get stronger as the detonation pattern, controlled by a computer programme worked its way down.’ (Griffin TNPH, p.19)



This is easily shown to be fallacious. Firstly, as the one of Columbia authors confirmed in a later email, their seismic data “are far too weak in signal-to-noise ratio and far too speculative in terms of signal source to be used as a means of contradicting the impact times …” (Commission, p.462) But the key mistake however, is the idea that any building is demolished by a progressive wave of explosions either working its way up or down a building.



Popular Mechanics gives a good account of why the seismic spikes do not support the CD theory: Debunking the 9/11 Myths: Special Report - Popular Mechanics.

Brent Blanchard devotes section 4 of his paper to the issue of seismic recordings on 9/11. Blanchard is Senior Editor of ImplosionWorld, a website which posts details of explosive demolitions, and also Director of Field Operations at Protec Documentation Services, Inc. Protec works in the field of vibration monitoring and structure inspection, a key service to both the construction and demolition industries. Vibration monitoring performed by independent experts has long been considered crucial for companies carrying out explosive demolition, because owners of nearby buildings are keen to sue if any cracks or other structural damage appears. The field seismographs used by Protec and others provide the key scientific evidence for disturbances that may have caused damage, and there were a number of such seismographs operated by Protec on 9/11 in the vicinity of Ground Zero, for monitoring construction sites. Blanchard tells us that data from these machines, and seismographs operated elsewhere, all confirm single vibration events recording the collapse. None of them record the tell-tale 'spikes' that would indicate explosive detonations prior to collapse. In his words:


This evidence makes a compelling argument against explosive demolition. The laws of physics dictate that any detonation powerful enough to defeat steel columns would have transferred excess energy through those same columns into the ground, and would certainly have been detected by at least one of the monitors that were sensitive enough to record the structural collapses. However, a detailed analysis of all available data reveals no presence of any unusual or abnormal vibration events.


3.4 Sudden Onset of Collapse ‘Consistent with Demolition’



This is one of the central myths of the CD theory. NIST show clear photographic evidence of the bowing of the exterior walls and collapse of interior floors in both Towers, with timings showing an acceleration of this bowing prior to the initiation of collapse. There was no sudden onset of collapse consistent with demolition. On the contrary the CD theory is unable to explain the bowing and other structural deformations prior to collapse. Eyewitness accounts from firemen also confirm a huge bulge in the south elevation of WTC 7 prior to collapse, the phenomenon more than any other that persuaded fire chiefs to withdraw their forces from danger.


3.5 Core Columns ‘Should Have Remained Standing’



Many CD theorists make the assertion that the ‘core columns should have remained standing’ during the collapse of the Towers, presenting the metaphor of records (as floors) sliding down the central spindle (as the building core). But they do not consider the NIST explanation which points out that the core columns were designed only to withstand compressive loads, whereas the outer columns were the ones designed to withstand all lateral loadings (principally winds up to hurricane speed). As each floor collapsed it would have created lateral forces on the core columns which were sufficient to either tear away the bolts or sever the columns themselves as they ‘peeled’ away from the centre. If the CD theorists insist that explosives were used to sever the core columns, then this commits them to a variant of the CD theory requiring explosives on every single floor, multiplying the tonnage of explosive required by a factor of around 100. It also commits them to a sequential detonation, which would travel down in the Towers and up in WTC 7, requiring technologies well beyond anything seen in industrial practice.


3.6 Explosions in the Sub-Basement



In an afterword in Jones’s paper he reports an eye-witness statement from William Rodriguez:



“My basis was, like I told the Commission, there was an explosion that came from under our feet, we were pushed upwards lightly by the effect, I was on basement level 1 and it sounded that it came from B2 and B3 level. Rapidly after that we heard the impact far away at the top.”



Jones takes this as evidence for the CD theory, firstly that explosions were heard or experienced at the ground or basement level, and secondly that subsequent sounds were heard, assumed to be the impact of the planes. The IF theory as elaborated by NIST accounts only for the ‘explosions’ at ground and basement levels: these were due to the fuel-air mix forced down shafts that had been opened up at the impact levels by the destructive impact of the planes. NIST report that not only a fuel-air mix was propelled down the shafts in the core of the building, but the force of these was sufficient to smash lift cages to the ground. People were killed and injured in these events, and windows were blown at the concourse level.


4 David Ray Griffin and the Dustin Mugford DVD



A DVD produced and directed by Dustin Mugford is distributed by 911revisited.com and is called ‘September 11 Revisited: Were Explosives Used to Bring down the Buildings?’ I regard the DVD as a good example of the kind of one-sided propaganda that pressure groups use to convey their beliefs. It is propaganda because it deploys the classical rhetorical techniques of loaded terminology and repetition of its message, and it is one-sided because it pretends, as do all the counter-orthodoxies, that there is only the official version and the counter-orthodoxy. They do not mention the groups I have referred to above, which, independently of any official or Federal account, set out to disprove the counter-orthodoxies, offering evidence that would make the arguments balanced.



The film opens with the repeated use of the word ‘explosive’ in such a way as to reinforce, in advance, the thesis put forward, that explosives brought down the WTC buildings. A range of eye-witnesses use the term in their accounts, but we have argued above (section 2.7) that no eye-witness has been played audio tapes of the signature ‘crack’ of demolition explosives and asked to estimate their similarity or otherwise to the reports they recall hearing on the day. Characteristic of the appeal of the entire counter-orthodoxy is the single phrase uttered by a reporter in one of the clips looking on as the destruction unfolded: ‘This defies belief’ (13:54 into the video). This is a natural response for the lay person, but the trained scientist should not then reach for the apparently easy explanation for it all: explosives.



At 18:53 into the video a reporter reminds us that Jones is putting his ideas forward as a hypothesis only, not as fact, and is calling for a fresh investigation to establish the truth. But David Ray Griffin, speaking next on the video, says: ‘The collapses of the Twin Towers and building number 7 had to have been examples of controlled demolition, brought about by thousands of explosives, placed throughout each of the buildings.’ Griffin, not a trained scientist, but a philosopher and theologian, has made the unforgivable error in science: to jump from a statement of hypothesis to a statement of fact. He is speaking from a podium marked ‘University of Wisconsin, Madison’ and delivers these lines with gravity and simplicity. A lay audience is inevitably impressed by his status as an academic, and the setting of the talk. They were given no chance to contemplate the possibility that the ‘thousands of explosives’ were merely a theory, based, as I have shown, on a complete misunderstanding of the science and practice of industrial explosive demolition. But Griffin, not prepared to wait for the further scientific investigation that Jones is calling for, has already made his mind up. He continues: ‘No foreign terrorist could have obtained the kind of access to the buildings this would have required.’



Griffin, untrained in science, and seemingly completely unaware of the actual nature of explosive demolition states the CD mantra: ‘The buildings collapsed straight down and at virtually freefall speed, as in controlled demolitions.’ We have seen that WTC2 certainly did not collapse ‘straight down’, and that the ‘virtually’ freefall speeds in controlled demolitions, are nothing to do with explosives, but are purely gravity powered.



Untrained in science, but well-versed in public speaking, Griffin smiles at the audience and says: ‘Try this: take a piece of concrete, and drop it a little over a thousand feet, and see if it pulverises into very fine dust. It won’t happen.’ But we have shown that the pulverisation of concrete in conventional explosive demolition has, again, nothing to do with explosives. It is gravity that reduces the buildings in controlled demolition to rubble and dust: the thousands of tons above the piece of concrete, acting something like a hydraulic press, are what smashes it. The mgh energy in each of the Towers, to repeat the point, was equivalent to 270 tons of TNT: no additional explosives were needed. Griffin also suggests that the very high temperatures in the basement rubble of the Towers ‘points to the existence of very powerful, precisely placed explosives.’ But explosives are incapable of heating up any significant quantity of metal, because their energies are dissipated in fractions of a second as shock waves. Their use in controlled demolition is to cut, not to pulverise or to heat or melt.



Griffin goes on to ridicule the official ‘pancake’ theory. He says, with a grin inviting the audience to share in the joke: ‘Now, even if this theory were remotely plausible, can you imagine it pancaking at freefall speed?’ Note that Griffin has moved on from ‘virtually’ freefall speed to straight freefall speed: bad science. As I have shown however, whatever the difficulty in imagining pancaking taking place at these high speeds, it is the practice of controlled demolition that proves Griffin completely wrong again. The speed of pancaking in conventional explosive demolition has nothing to do with the use of explosives: it purely gravity powered.



The Griffin section of the video concludes with the issue of the core columns and the idea that they should have remained standing even if the floors did pancake according to the official theory. He uses the analogy of records stacked up above a turntable moving down, but leaving the spindle intact. But, instead of considering the physics of a vertical column, designed for compressive not lateral loading, pulled away from the vertical by the collapsing floor members, and asking whether the estimated shear loads were sufficient to fracture them or to break the joints, Griffin resorts to another popular 9/11 myth: that the 9/11 Commission Report deny the very existence of the core columns. He says: ‘It avoided the problem, incredibly, by simply denying the existence of these columns. … This supposedly authoritative report said that the interior core of the buildings was a hollow steel shaft in which elevators and stairwells were grouped. Such a desperate lie is a sure sign of a cover-up.’



It would indeed be a ‘desperate lie’ if the final report actually denied the existence of the core columns. It is true, in fact, that the Commission Report includes this statement: ‘…These exterior walls bore most of the weight of the building. The interior core of the buildings was a hollow steel shaft, in which elevators and stairwells were grouped.’ But this statement is tucked away at the end of the document (on page 541 of 567) as part of a footnote to page 278. The purpose of the footnote was generally to direct the reader to the FEMA report which contained more details on the building. But the Commission Report never set out to give an account of the collapse of the buildings, as that task was completed in broad terms in the FEMA report, and in much more detail in the NIST report, both of which deal extensively with the core columns. The NIST report has this to say on the question of loading between the exterior columns and the core columns:



The dense array of columns along the building perimeter was to resist the lateral load due to hurricane-force winds, while also sharing the gravity loads about equally with the core columns. [NCSTAR 1, p.6]



So, how much of a desperate lie are the offending few lines tucked away in a footnote at the end of the Commission Report? It is clearly not accurate, as the gravity loads are shared equally across the two types of column (though the exterior columns bore all of the lateral weightings). But to the lay audience at Madison University Griffin’s account would suggest that the official reports as a whole had conspired to deny the importance of the core columns, or even their existence. Anyone who has read the FEMA and NIST reports with their focus on technical issues, and who can see from the Commission Report that it did not set out in any of its chapters to give an account of the mechanics of collapse, must conclude that it is Griffin who is perpetuating a lie.



What then of Griffin’s two books on the subject: The New Pearl Harbour (TNPH), and The 9/11 Commission Report (TNCR)? In both books Griffin repeats what I believe to be the bad science put forward by Jones and others, with no attempt to balance their claims with those by other technical experts, official or otherwise. And, as the TNCR title suggests, he repeats in it his absurd claim that the official reports omit the core columns (p.27). Here is an extract:



With regard to the more basic question – Why did the Twin Towers collapse at all? – the Commission implies an answer by saying that



the outside of each tower was covered by a frame of 14-inch-wide steel columns. … These exterior walls bore most of the weight of the building. The interior core of the buildings was a hollow steel shaft, in which elevators and stairwells were grouped. (541n1)



This implicit explanation, however, involves a complete falsification, because the core of each tower was composed not of a “hollow steel shaft” but of 47 massive steel columns, …



Griffin concludes the section by saying ‘The Commission avoids this embarrassing problem by simply denying the existence of those massive steel columns – therefore either demonstrating enormous ignorance or telling an enormous lie.’ Enormous lie? A paragraph buried in the footnotes at the end of the document which, true, is inaccurate, but by no stretch of the imagination can be an answer to the question: Why did the Twin Towers collapse at all? Why on earth should anyone believe that this document chooses to answer a very complex technical question by a remark buried in the footnotes, the purpose of which footnote is to refer the reader to the FEMA report? Why should anyone believe that the Commission are guilty of ‘either enormous ignorance or telling an enormous lie’ in connection with the Twin Towers collapse when the technicalities of this event are thoroughly dealt with in the FEMA and NIST reports, both of which deal extensively with the core columns?



I regret to say that I have found both of Griffin’s books to be on a par with the Dustin Mugford DVD: that is they are one-sided propaganda. It would take a book-length refutation to fully answer Griffin, but I believe that the discussion here shows him to be an unreliable thinker on such complex issues. I think it instructive however to ask the question why his methods of argument seem so persuasive to many. His approach seems to be to multiply accusations, without giving each point a careful and balanced discussion. A friend of mine suggests that this approach in argument is like a rope made from many threads: each thread on its own may be weak, but the rope as a whole is strong. Appealing as this image is, I cannot shake off the suspicion that, in argument, as opposed to making ropes, this method is alarmingly like mud-slinging.



I will give an example: Griffin states early on in TNCR that ‘One problem is that at least six of the nineteen men officially identified as the suicide hijackers reportedly showed up alive after 9/11’ (p.19) This is naturally intriguing, so I Googled the first name he cites: Waleed M. al-Shehri, and the first site I encountered was the Wikipedia entry for the hijacker. Wikipedia has this to say:



Waleed and Wail were both mistakenly reported to have been found alive and well, by the BBC later in 2001. They were initially reported in error by a Saudi newspaper editor as the sons of Ahmed Alshehri, a senior Saudi diplomat stationed in Bombay, India. On September 16, 2001, the diplomat Ahmed Alshehri denied that he was the father of the two hijackers. Wail claims he did attend Embry-Riddle Aeronautical University in Daytona Beach, Florida - but was the victim of mistaken identity, since he used that training to secure his current position with a Moroccan airline company. Saudi Arabia has confirmed his story, and suggested he was the victim of identity theft.



Why doesn’t Griffin mention the opinion of Wikipedia and the Saudi government, and allow the reader to decide? The muddle over the transliteration of Arabic names is endemic in the relationship between the US and the Islamic world, and is part of the wider cultural gap that allows for such misunderstandings to proliferate. Griffin goes on to say:



How can we believe that the Commission’s report was based on “exacting investigative work,” as we are told by Kean and Hamilton in the Preface, if the staff did not even learn, from sources such as the Associated Press, the Telegraph, and the BBC, that six of the men originally identified as hijackers were still alive?’ [TNCR p. 20].



But I would reply to Griffin: how can we believe your books when you don’t check up on anything, whether it is the science of demolition, or erroneous reports by the BBC?



It seems to me that Griffin is content to pick up on any accusation germane to his thesis, and bind it into his ‘rope’ without giving the reader any suggestion that evidence exists to the contrary. By moving breathlessly from one such accusation to another, he draws the reader along to his grand conclusion: to me it seems more like mud-slinging than a coherent argument. He also seems to revel in calling any official who changes their mind on any of the events of 9/11 ‘revisionists.’ This is an extraordinary word to use, deriving I believe from the Communist era, and intended to discredit through the emotional charge that the word carries. But good science is always open to revision, and the fact that an investigator changes their mind as new evidence emerges is a positive sign, not immediate proof of conspiracy.


5 Conclusions



Good science involves the slow development of theories based on careful checking and re-checking of data. Hence I am surprised that Professor Jones, trained in science, should be so hasty in his presentation, including the apparent unwillingness to properly investigate the science and practice of explosive demolition, and the even graver errors such as assertions that a large section of the Twin Towers was reduced to dust in mid-air, when video footage clearly shows the section he refers to falling as a whole (and fully conserving angular momentum.) I am not surprised however that David Ray Griffin, as a theologian and philosopher, should be utterly cavalier about scientific evidence in particular and other evidence in general. My studies of the Enlightenment philosophers showed that they collectively may have been inspired by the emerging discipline of physics, but completely failed to grasp its workings and real significance, and resented its emerging cultural prominence. From Hume onwards, philosophers have sought to reclaim what they had regarded as their birthright: the cultural status of philosophy as the ‘queen of sciences.’ Rorty represents the ultimate postmodern rejection of good science: Griffin merely ordinarily ignorant of it.



I leave the author of the Debunking 911 site the last word, sentiments I wholeheartedly agree with:



This is the kind of thing the "scholars" want us to pay millions more investigating. Personally, I could think of a few other pressing issues to spend millions on. Like research into the collapse of critical thinking skills in American and UK universities.



[See Debunking 9/11 Conspiracy Theories and Controlled Demolition - Squibs, bottom of page.]
 
. .
Good Science and 9-11 Demolition Theories




This paper is written to demonstrate that those who believe that the World Trade Centre was destroyed by controlled demolition, rather than the impact of the planes, are mistaken. While I sympathise with the overall aims of protesting against US and UK foreign policy, I don't believe that US officials took part in a conspiracy to murder thousands of their fellow-citizens. I believe that the truth is in fact more alarming: US and UK foreign policy is based on ignorance, not malice. But I don't believe in fighting ignorance with ignorance. However well-intentioned, the demolition theories will not achieve their goals because they are based on an ignorance of good science.






Good Science and 9-11 Demolition Theories










1 Introduction

1.1 Background

1.2 The Counter-Orthodoxies and Counter-Counter-Orthodoxies

1.3 Motivation

1.4 Jones&#8217;s Scientific Evidence and the Science and Practice of Demolition

1.5 Some Basic Concepts in Physics

1.6 What is Good Science?

2 Jones&#8217;s Evidence Refuted

2.1 Molten Metal: Flowing and in Pools

2.2 Observed Temperatures around 1000&#176;C and Sulfidation in WTC 7 Steel

2.3 Near-Symmetrical Collapse of WTC 7

2.4 No Previous Skyscraper Collapse Due to Fires

2.5 Squib-timing during the Collapse of WTC 7

2.6 Early Drop of North Tower Antenna

2.7 Eyewitness Accounts of Flashes and Loud Explosions

2.8 Ejection of Steel Beams and Debris-plumes from the Towers

2.9 Rapid Collapses and Conservation of Momentum and Energy

2.10 Controlled Demolition &#8220;Implosions&#8221; Require Skill

2.11 Steel Column Temperatures of 800&#176;C Needed: A Problem in the Argument of Bazant and Zhou

2.12 Problems in the NIST Report: Inadequate Steel Temperatures and Tweaked Models

2.13 NIST's Failure to Show Visualizations

2.14 Jones&#8217;s Summary

3 Additional Arguments for the CD Hypothesis

3.1 Timing of Tower collapses

3.2 Energy Required to Pulverise Concrete

3.3 Seismic Recordings

3.4 Sudden Onset of Collapse &#8216;Consistent with Demolition&#8217;

3.5 Core Columns &#8216;Should Have Remained Standing&#8217;

3.6 Explosions in the Sub-Basement

4 David Ray Griffin and the Dustin Mugford DVD

5 Conclusions






1 Introduction


1.1 Background



The events of 9/11 are widely recognised to be a defining factor in the early unfolding of world history in the 21st century. From this single audacious attack on the US, conflicts in Afghanistan and Iraq flow directly, along with terrorist attacks on Madrid, Bali, and London. Arguably the July 2006 war in Lebanon and the Gaza Strip, waged between Israel on the one side, and Hamas and Hezbollah on the other, is also shaped by the aftermath of 9/11. Domestic and foreign policies of most of the world&#8217;s nations have changed as a direct consequence of the attack.



Hence it is of great interest to many different groupings to ascertain the truth of the 9/11 attacks. Broadly speaking there exists the official line, generated by various US Government sponsored investigations, and the counter-orthodoxy, comprising a range of views. On the official side there are three key reports:



1. FEMA (Federal Emergency Management Agency)

2. NIST (National Institute of Science and Technology)

3. 9/11 Commission



Broadly speaking these reports agree that a group of 19 Muslim men, armed only with box-cutters (penknives), hijacked 4 domestic flights, three of which hit their intended targets, and one of which crashed in a field after passengers fought back. AA flight 11 crashed into the North Tower of the World Trade Centre (WTC); UA flight 175 crashed into the South Tower of the WTC; and flight 77 crashed into the Pentagon. The official theory holds that planes which hit the Twin Towers caused structural damage on impact, stripped away insulation from steel columns and severed water sprinklers; caused fires to rage; and eventually they collapsed causing widespread destruction to many other WTC buildings, and, later in the day, the complete collapse of building WTC 7.



Those adhering to the various counter-orthodoxies do not accept that 19 Muslim men, armed only with box-cutters, could achieve such destruction, and believe that the events were part of an official conspiracy. In this paper I will focus mainly on the claims that the Twin Towers and WTC 7 were destroyed by controlled demolition (as part of this conspiracy), rather than the result of the impact of the planes and the subsequent fires. My aim is to show that the scientific basis for these claims is weak or non-existent.



Mostly I will avoid using the loaded term &#8216;conspiracy theory&#8217; for the counter-orthodoxy, partly because the official account is also, of course, a conspiracy theory. Instead I will use the term &#8216;controlled-demolition-theory&#8217; or just &#8216;CD theory&#8217; for the counter-orthodoxy, and the term &#8216;impact-fire-theory&#8217; or just &#8216;IF theory&#8217; for the official account, where they deal with the collapse of the WTC buildings.


1.2 The Counter-Orthodoxies and Counter-Counter-Orthodoxies



But who are the groups or individuals challenging the official account? In this paper I focus on a single scientist, Steven Jones, whose work is widely cited by CD theorists, to support their wider challenge to the official line. Another key figure is philosopher and theologian David Ray Griffin, whose two books on the subject are amongst the most radical, and effectively accuse a range of US officials of mass murder. Whole organisations exist however to challenge the official account, including:



* 911Truth.org 911truth.org ::::: The 9/11 Truth Movement
* 9-11 Research 9-11 Research: An Independent Investigation of the 9-11-2001 Attack
* Reopen911.org ReOpen 911 - Welcome to 1984!
* 9-11 Visibility Project www.septembereleventh.org: 9-11 Visibility Project



The events of the day, and the technical details surrounding them are immensely complex, and the counter-orthodoxies have thrown up a wide variety of objections to the official line. I will focus mainly on the controlled-demolition theories, and in particular at the science behind them. What is interesting is that a range of individuals and groups are attacking the counter-orthodoxies, and presenting scientific arguments that refute them. I urge anyone who believes that the argument is merely between the official line and the counter-orthodoxies to look at the following sources which independently argue against the counter-orthodoxies:



* Debunking 911 Debunking 911 Conspiracy Theories and Controlled Demolition Homepage
* Representative Press WTC Pre-Collapse Bowing Debunks 9/11 "Controlled Demolition" Theory
* Snopes http://www.snopes.com/rumors/pentagon.htm
* Popular Mechanics Debunking the 9/11 Myths: Special Report - Popular Mechanics



There is also a crucial paper by Brent Blanchard on the Implosion World website at: http://www.implosionworld.com/Article-WTC&#37;20STUDY 8-06 w clarif as of 9-8-06 .pdf. This paper alone should end any credulity towards the demolition theory, though its points need more elaboration for a non-technical audience. The reason that I highlight this paper is because it is the only one to date written by an authority on controlled demolition, based on access to data not available to either the official account or the counter-orthodoxy. I consider this paper so important that I would recommend reading it before the rest of this text, or in parallel, as I shall make numerous references to it. In case the link to the Implosion World site should change or be down, I have made the paper available from my site here: Implosion World Paper.



I will draw on the scientific points of the above sites and papers where appropriate.



I want to add here that I think that the publication of books and the existence of websites all devoted to the counter-orthodoxies &#8211; which effectively accuse the US Government in general, and range of individuals in particular, of mass murder of fellow-US citizens &#8211; are a tribute to Western principles of democracy and freedom of expression. By the same token I am free, along with others, to publish works that challenge the counter-orthodoxies. I want to make it absolutely clear however that I do not support the US Government in its response to 9/11. I simply believe that the approach taken by those who accuse it of complicity in the attacks is misguided. I believe that these accusations will founder on a lack of evidence, and that the same energy could be used to work, using democratic principles, to show where Bush and his colleagues have really gone wrong. I believe this to be their blanket refusal to learn about Islamic culture, history, and tradition; in particular their failure to credit radical Islamic movements their valuable and popular socialist and welfare dimensions; and their attempt to impose Western values on Islamic countries by force.



If you doubt my anti-Bush credentials, please visit a site I created to honour the civilians of Afghanistan killed by US bombing in its subsequent campaign: The Twin Tragedy. I greatly regret not continuing work on this, but I believe that Professor Marc Herold, who supplied most of the statistics, has continued in his efforts to make known that fact that approximately the same number of innocent Afghan civilians died in the US-led invasion as did US civilians in 9/11.


1.3 Motivation



I have spent my academic life researching the intersections between art, science and religion, and have not been drawn up to this point to contemplate in any detail the events of 9/11. However two friends and colleagues have been deeply persuaded of the counter-orthodoxy, principally by Griffin, and to some extent Jones, so I emailed some initial comments objecting in general terms to what I saw, and still do, as a &#8216;conspiracy theory&#8217; of the worst kind. When I say &#8216;worst kind&#8217; I mean that the theory betrays the fundamental principles of what I hold good science to be. My first degree was a joint honours in Physics and Chemistry, and later on I completed an MSc in Software Engineering and have written hundreds of thousands of lines of code for big graphics programmes. Jointly these experiences have persuaded me that &#8216;Good Science&#8217; is a matter of slow and careful investigation of data, with the continual awareness that one&#8217;s own emotional commitment to one result or another tends to make it overwhelmingly tempting to jump to conclusions ahead of the due process. Debugging large software programmes is very similar to the detective work in crime investigations, only one is personally the &#8216;criminal&#8217; and even more likely to have an investment in one&#8217;s theories. Looking at the writings of those challenging the official line, I find little evidence of good science in this sense: it seems that the individuals promoting these ideas are already persuaded of their version of the &#8216;truth&#8217;. My interest in 9/11 is therefore partly personal &#8211; I am hoping to dissuade my friends of their adherence to the counter-orthodoxies &#8211; and partly that I believe in &#8216;Good Science&#8217; as the basis for much more than academic arguments over the interpretation of events. I believe in &#8216;Good Science&#8217; as fundamental to what we cherish, though often without naming them such, as &#8216;Enlightenment Values.&#8217;


1.4 Jones&#8217;s Scientific Evidence and the Science and Practice of Demolition



In Section Two I will focus on the scientific evidence put forward by Professor Steven Jones in his online paper at http://www.physics.byu.edu/research/energy/htm7.html entitled &#8220;Why Indeed Did the WTC Buildings Collapse?&#8221; He presents his evidence under 13 headings, though in fact some include additional points, and some are effectively subsumed under other headings. His evidence is meant to convince us that the Twin Towers and WTC 7 were brought down by controlled demolition, meaning the use of explosives triggered in a sequence similar to that used in legitimate explosive demolition. The bulk of this paper is devoted to Jones&#8217;s 13 headings, showing in detail why I think he is wrong on every count.



I believe, as a scientist, that Jones&#8217;s principal error is not to research the science and practice of explosive demolition. It is quite understandable when lay persons repeat the oft-cited 9/11 opinion: &#8216;it looked like controlled demolition.&#8217; A good example is Hollywood actor Charlie Sheene recounting his reaction to 9/11 in a TV interview: &#8216;I said, &#8220;call me insane, but did it sorta look like those buildings came down in a controlled demolition?&#8221;&#8217; (You can see this in a DVD distributed by one of the counter-orthodoxy groups, 911revisited.com at www.911revisited.com; I comment on the DVD in section Four of this paper.) But it is the job of a scientist not to be fooled by appearances: a scientist knows that fool&#8217;s gold isn&#8217;t gold and the leaf-moth isn&#8217;t a leaf. A physicist also knows well that much of physics is deeply counter-intuitive, for example that heavy bodies fall at the same speed as light ones, that the earth rotates, is round, etc.



I will now sketch an outline of the science and practice of explosive demolition, though the finer points will become apparent in the arguments to follow. First of all, the art of bringing a tall building down by the use of explosives is not a widely disseminated field of engineering, being rather the specialist domain of a few dozen top international companies, often family-run. Hence there are not many books on the subject, and the Internet now is more likely to point to Jones&#8217;s paper on the subject than any useful technical review.



However, the web site How Stuff Works (HowStuffWorks "Science Channel") has a short section on explosive demolition that is informative, and begins with this description:



The basic idea of explosive demolition is quite simple: If you remove the support structure of a building at a certain point, the section of the building above that point will fall down on the part of the building below that point. If this upper section is heavy enough, it will collide with the lower part with sufficient force to cause significant damage. The explosives are just the trigger for the demolition. It's gravity that brings the building down.



The key physics is elucidated here: that it is gravity which brings the building down. More than that, it is gravity that smashes concrete walls and floors into rubble, and it is gravity that is responsible for the sometimes vast clouds of dust and debris that billow out from the site. The explosives used have a marginal additional effect in converting the structure into rubble and dust: their job is to cut supports, often in a carefully timed sequence. Brent Blanchard puts it like this: 'Since their inception in the late 1800s, blasting engineers have understood that building implosions work best when the forces of gravity are maximised. This is why blasters always concentrate their efforts on the lowest floors of the structure. While smaller supplemental charges can be placed on upper floors to facilitate breakage and maximize control as the structure collapses, every implosion ever performed has followed the basic model of obliterating structural supports on the bottom few floors first, "to get the structure moving."'



Two types of explosive demolition are carried out: &#8216;toppling&#8217; and &#8216;implosion&#8217;. Toppling involves the placing of explosive charges to cut out the support structure on one side only of a building, causing the structure to rotate as it collapses, generally into an open lot where it can do no damage. Implosion involves the more symmetrical placing of charges in order to bring the building down symmetrically into its own &#8216;footprint&#8217;. It is the near-symmetrical collapse of the Twin Tower and WTC 7 that has drawn many lay observers to the belief that they were brought down by controlled explosive demolition &#8211; &#8216;implosions&#8217; that could only be achieved by very skilled operators. Unfortunately for the CD theorists the skilled operators &#8211; those in the business of carrying out implosions on contracts worth millions of dollars &#8211; don&#8217;t share this belief.


1.5 Some Basic Concepts in Physics



Readers can skip this for now, but I want to outline some very simple and fundamental concepts in physics needed to negotiate the scientific claims and counter-claims of the IF and CD theories. (I promise that this is very brief and easily accessible to the lay person.)



The first is that when an object is raised to a height, it gains what is known as gravitational potential energy. As Loizeaux says: &#8220;Every nail that was carried up in the pocket of some construction worker is potential energy that&#8217;s at our disposal, &#8230;&#8221; In terms of physics the potential energy is calculated by the formula



E = mgh



E is the energy, m is the mass (of the nail or any other object), g the acceleration due to gravity, and h the height that the object is raised. If m is in kilograms, g in metres per second per second, and h in metres, then E is measured in a unit called Joules. When the Loizeaux family demolish a building in an implosion they are liberating this stored potential energy as kinetic energy &#8211; the energy of movement. This energy is calculated by a different formula:



E = &#189; mv2



In this case the kinetic energy in Joules is equal to half the mass of the moving object times the velocity squared. When the collapsing building hits the ground the kinetic energy is converted into other forms, such as fracture energy (energy required to break, for example, concrete into rubble), sound energy, and heat energy. To give some pertinent examples, the gravitational potential energy (mgh) of one of the Twin Tower has been estimated at 1.139 x 1012 Joules. This is roughly 1 followed by 12 noughts or a billion times a billion Joules (an American trillion). To put that in perspective, it is roughly the same energy as 272 tons of TNT exploding, or enough to melt one thousand metric tonnes of steel. The impact of the faster of the two planes released kinetic energy (&#189; mv2) roughly equal to 4 x 1009 Joules, or four thousand million Joules. This is enough to melt approximately 4 metric tonnes of steel.



Of course, the energy released by the collapse of the Towers or the impacts of the plane did not go into melting tonnes of steel (though a small fraction may have). The point here is to understand the colossal energies involved in the WTC disaster, and how they are estimated in physics. Also vital to understand is the law of conservation of energy, which requires that all the energy that disappears in one form must appear in an other form or forms.



We will see that a key debate in the IF vs. CD theory is as to whether there was enough gravitation potential energy (mgh energy) in the buildings to account for the pulverisation of them into such fine dust and rubble. It is also helpful to be able to compare the mgh energy of the buildings to any proposed energy that the CD theorists believe to have come from explosives.



The additional scientific concept that needs to be introduced is more nebulous, but critical: it is complexity theory (also broadly called chaos theory). While pure physics (of the kind that Newton&#8217;s revolution in science introduced to the world) deals with very simple systems, the real world is not just a bit more complicated: it is orders of magnitude more complicated. Newton was able to make his stunning breakthrough in astronomy (in brief, the inverse square law of gravitation) because he focussed on two bodies at a time, i.e. the sun and any given planet, or a planet and its moon. It is well known in physics that the introduction even of a third body to the problem makes the mathematics almost intractable. If we scale up the problem to a natural event like the collapse of the Twin Towers, then we are dealing with a vast number of bodies interacting with each other. Chaos theory tells us a very sobering fact about a complex system like this: minute variations in the input factors for a complex system lead to wildly varying outcomes. This is why explosive demolition is part science, but also part art. Like all experts in real-world events, implosionists are masters of their total body of experience, constituting what influential writer Donald Schon has called &#8216;tacit knowledge.&#8217; When CD theorists cite as evidence that &#8216;no steel-framed building has ever collapsed before as a result of fire&#8217; they are ignoring complexity theory, which requires only that small differences in the original parameters result in a novel outcome. The question we shall explore is whether the impact of a passenger jet into a steel-framed building makes that &#8216;small&#8217; difference or not.


1.6 What is Good Science?



For me, good science is far more than accurate science. &#8216;Accurate representation&#8217; for philosopher Richard Rorty is &#8216;simply an automatic and empty compliment which we pay to those beliefs which are successful in helping us do what we want to do.&#8217; [Rorty, Richard, Philosophy and the Mirror of Nature, Princeton, New Jersey: Princeton University Press, 1979, p. 10] I find this quintessentially postmodern approach to science not just inadequate but actually painful: my love of science has been lifelong and born out of its extraordinary ability to penetrate the world of appearances and find laws whose predictive powers are the basis of our modern technological lifestyles. More than just &#8216;helping us do what we want to do&#8217; however, I believe that the birth of science with Newton and others was the genuine basis for the Enlightenment and the values that flowed from it and which are the basis of what is best in the modern world. Above all, science taught the great thinkers of the Enlightenment that there was a way beyond personal prejudice and superstition in the settling of the affairs of society, a way of settling dispute based on evidence. Difficult as this path is, there lies an even more important lesson from science: when the evidence is not available then we are obliged to say: we don&#8217;t know. Science is not often promoted as the discipline which teaches us what we don&#8217;t know, but for me that is the essence of good science. The Witchfinder General only allowed the possibility that the accused man or woman was a witch or was not. &#8216;We don&#8217;t know&#8217; was not an option, and the most absurd evidence was concocted to fill the vacuum.



For us to really know something in science we have to start with a simple system, isolate it from variables that enter from outside, and above all, be able to repeat the phenomenon under scrutiny. The WTC attack is as far removed from this as one can get. Only identical structures under identical impacts could form the basis for certain knowledge as to whether or not the impacts could cause the collapses. But when we examine both the wilder and the more sober adherents to the counter-orthodoxies and to the controlled demolition theory, we find a universal unwillingness to accept that &#8216;we don&#8217;t know&#8217; what happened. Not at least with the kind of certainty available to the phenomenon in controlled laboratory experiments.



The most common complaint from the counter orthodoxy is &#8216;I can&#8217;t believe that &#8230;&#8217; followed by a specific from the event. For example eye-witness accounts confirm that after impact on WTC 2 a blast blew out windows in the ground floor lobby and hurled people to the ground. The official account suggests that the kerosene-air mixture from the impact zone high up in the tower was forced down the lift shafts and other ducting by a fireball, causing the damage. Martin Sheene, speaking in the same TV interview, said: &#8216;I have a hard time believing that a fireball travelled down the elevator over 1100 feet and still had the explosive energy to destroy the lobby like it was described.&#8217; One can sympathise with this point of view, but good science goes beyond pub talk like this: it starts by not pre-judging. Instead it investigates.



I need to make another point on good science here: the question of publication in refereed journals. The CD theorists are largely drawing on unpublished scientific papers. There is of course good science that is refused publication, and there is of course bad science that does get published, but these are exceptions, and on the whole what publication means is that experts in the field have checked the assumptions, experimental procedures, calculations, and flow of the argument that make up the paper. Even the most polymathic of scientists find this difficult to do outside of their own discipline.


2 Jones&#8217;s Evidence Refuted



This section refers to Professor Steven Jones&#8217;s paper, widely available on the Internet, for example at: http://www.physics.byu.edu/research/energy/htm7.html. It is worth having this to hand in following the arguments in this section. I have used his thirteen section headings verbatim. Jones gives a summary of his argument at the beginning of his paper, but I will start with the detailed arguments in the sections that follow the summary.


2.1 Molten Metal: Flowing and in Pools



Eye-witness accounts of the presence of molten metal at high temperatures in the basement rubble of the Twin Towers and WTC7 have led Jones to speculate that the industrial compound thermite was responsible, and is hence evidence for the CD theory.



Jones: &#8220;I maintain that these observations are consistent with the use of high-temperature cutter-charges such as thermite, HMX or RDX or some combination thereof, routinely used to melt/cut/demolish steel.&#8221;



But thermite is an incendiary, a vastly different product to HMX and RDX which are military explosives like TNT that can be used in civilian demolition projects. Thermite is a slow-burning product in comparison, does not explode, and, as far as I can determine, is never used in demolition of buildings. It can be used to melt horizontal pieces of steel, because it produces molten iron at up to 2,500 degrees centigrade, which flows onto the target and melts it. It cannot be used to melt vertical structures, because the molten iron simply flows past the target. Thermite is used to quietly destroy military equipment such as artillery (by inserting it down an up-pointing barrel), but more regularly in construction, for example, to weld rails together.



Hence the CD theory is not supported by the quantities of molten metal, because thermite in its conventional form is useless in demolition: it is slow-burning, with unpredictable time to melt, and can only be used in direct contact with horizontal unclad steel beams / components. (The horizontal steel members in the Twin Towers were covered by at least 4 inches of concrete.) Prototype thermite cutter torches have been developed which could cut steel at any angle, but they work by producing as stream of high-velocity, high-temperature combustion products. Any iron produced by such a cutter would be dispersed as as droplets and would only in exceptional circumstances pool into any significant quantities of molten iron. It is more likely that a film of iron particles, mixed with aluminium oxide particles, would be deposited on nearby surfaces. However this is speculation on my part as I cannot find any reference to commercially available thermite cutter torches. If anyone can provide information on such devices I would be pleased to hear from them. Nano-thermites, mentioned by Jones, are also ruled out because they operate more like an explosive, and so would disperse iron particles as I suggest above. The thermite lance, a variant that uses a long iron tube with aluminium rods running through it, is ruled out as far as I can tell because it would require an operative.

HMX or RDX on the other hand, which can be used in demolition (though TNT seems to be more common), would not melt steel, because the high energy content of the material is released in very short timescales, designed, not to melt the target, but to fracture it.



Jones: &#8220;Observe the grayish-white plumes trailing upward from white "blobs" at the left-most extremities of the upper structure. (The lower structure is mostly obscured by dust.) It is possible that thermite cut through structural steel and that what we now observe is white-hot iron from the reaction adhering to the severed ends of the steel, with grayish-white aluminum oxide still streaming away from the reaction sites. The observations are consistent with the use of thermite or one of its variants.&#8221;



In the photograph provided there is only one white blob on the left-most extremity of the upper structure. Grayish white plumes seem to come from the whole structure, not the blob, and could be any kind of ash or powder. There is no significant resemblance either to the plumes emitted from the bag of thermite in Jones&#8217;s accompanying photo. Indeed the plumes in the WTC photo are indistinguishable from the billowing clouds of dust and debris around them.



More easily visible, and the subject of debate, is the stream of what looks like molten metal running from WTC 2 just below the impact zone.



Jones: &#8220;Who can deny that liquid, molten metal existed at the WTC disaster? The yellow color implies a molten-metal temperature of approximately 1000 oC, evidently above that which the dark-smoke hydrocarbon fires in the Towers could produce. If aluminum (e.g., from the plane) had melted, it would melt and flow away from the heat source at its melting point of about 650 oC and thus would not reach the yellow color observed for this molten metal. Thus, molten aluminum is already ruled out with high probability.&#8221;



To rule out aluminium so quickly is poor science, because we don&#8217;t know what the temperatures were in the impact zone, while we do know that many metric tonnes of aluminium constituting the plane were in the area just above the outflow of molten metal. Of course, the alternative hypothesis, that the molten metal was iron or steel, should be also considered carefully. The argument of Jones is that if the molten metal were steel, then it would support the CD theory. But the link between molten steel and controlled demolition is non-existent, as thermite is not used in controlled demolition. Hence Jones requires a variation on controlled demolition: controlled demolition plus the use gratuitous and incompetent use of thermite. We have to believe that the conspirators had researched controlled demolition so badly as to decide on the use of thermite. Now, Jones estimates that &#8220;Roughly 2,000 pounds of RDX-grade linear-shaped charges&#8221; would be sufficient to bring the building down, and such a quantity of explosive might conceivably have been hidden in each of the towers. But the quantity of thermite required to produce this stream of molten metal is much greater. 107 Kg of thermite is required to produce 54 Kg of molten iron, and the stream of molten metal flowing from the impact zone (if iron) has been estimated at thousands of kilograms. Even if the stream is only 1,000 kg of iron, then 2,000 kg, or two metric tonnes, of thermite would be required. But the CD hypothesis implies much more than this. For a start the thermite would have been distributed over the proposed target floor for initial collapse, so it would be very difficult for the molten iron products to pool in one place and pour out. Secondly, the CD hypothesis agrees that the floor(s) of impact of the plane could not have been exactly predicted, so every, say, 5 floors, another couple of metric tonnes of thermite would be required. (Jones: &#8216;&#8230; to make it appear that the planes somehow initiated the collapse; cutter-charges could have been pre-placed at numerous spots in the building, since one would not know exactly where the planes would enter.&#8217;) Even if only the top half of the building were so prepared, then we would anticipate 2 metric tonnes x 11 locations or 22 tonnes. If the mass of stream of molten metal were estimated at more like 10,000 kg of iron then the figure goes up to 220 tonnes of thermite. We have to believe (a) that the conspirators were ignorant enough to attempt to use thermite, and (b) could insinuate between 22 and 220 tonnes of thermite, plus charges, plus radio firing systems, into each tower.



If in addition, thermite is required by the CD hypothesis to account for the molten steel in the basement after collapse, then we have to add an addition two tonnes of thermite for every tonne of molten iron. The problem for the CD theory is in fact that no reliable estimates exist of the amount of molten metal, if any, in the basements.



To sum up, it is a tough job to for the CD hypothesis to account for the stream of molten metal as iron produced from thermite reaction because (a) the choice of thermite requires the conspirators to be incompetent, (b) pooling of the molten iron would require the odd concentration of thermite on a given floor in one location, and (c) the quantity needed (22-220 tonnes) would be hard to smuggle in and hide in the building. This quantity increases by two tonnes per every tonne of molten steel estimated to be in the basements.



The IF hypothesis suggests that the molten metal is aluminium (and other alloys used in plane construction), and that it pooled in that location because that is where the plane was. As Jones rightly point out however, the IF hypothesis would require the molten aluminium (and alloys) to attain temperatures several hundred degrees above melting point. The IF hypothesis also requires that the molten steel in the basement have been heated by a combination of fire and mgh energy, so much rests on estimates of those factors.



I want to add a hypothesis that may yet explain the high temperatures, and would need to be disproved by the CD theorists: that some of the aluminium in the planes was ignited on impact. I return to this issue later on.


2.2 Observed Temperatures around 1000&#176;C and Sulfidation in WTC 7 Steel



In Jones&#8217;s second section, he continues on the themes of high temperatures:



Jones: &#8220;combines aluminum/iron oxide (thermite) with barium nitrate (29%) and sulfur (typically 2% although more sulfur could be added). The thermate reaction proceeds rapidly and is much faster than thermite in degrading steel leading to structural failure. Thus, both the unusually high temperatures and the extraordinary observation of steel-sulfidation (Barnett, 2001) can be accounted for -- if the use of thermate is allowed in the discussion.&#8221;



I would suggest that the argument against thermite I presented above applies equally to thermate. Certainly, the sulfidation of steel is an additional argument in favour of thermate, but is mitigated against because of the difficulty of maintaining contact between thermate sulphur-rich molten-iron products and steel columns. Molten iron flows very fast, due to its high density, and would have only very short contact times with vertical steel members, which would have had to have their insulation previously stripped. We are left again with the issue of the thermite / thermate molten iron products perhaps pooling on an exposed horizontal steel member long enough to cause melting and sulfidation, unlikely because the horizontal members were covered in at least 4 inches of concrete.



Jones says: &#8220;While gypsum in the buildings is a source of sulfur, it is highly unlikely that this sulfur could find its way into the structural steel in such a way as to form a eutectic.&#8221; But why is this more unlikely than with thermate? Jones needs to present evidence that steel girders or columns, when exposed to burning thermate, result in sulfidation, and that the high temperatures and pressures of the collapse could not achieve sulfidation with the sulphur contained in gypsum (plaster). There are certainly interesting scientific questions here to which we don&#8217;t know the answers. But our ignorance is equal as to the two proposed processes, so at present we should marginally favour the theory that has a known source of sulphur: the gypsum.



You may like to look at the &#8216;Rethinking Thermite&#8217; pages on the Debunking 911 site for further arguments against Jones&#8217;s hypothesis (Thermite and Sulfer- Debunking 9/11 Conspiracy Theories and Controlled Demolition).

In Brent Blanchard's paper he devotes section 5 to the issue of thermite and molten metal. His team spoke directly to operators who cleared Ground Zero, and he concludes: 'To a man, they do not recall encountering molten structural steel beams, nor do they recall seeing any evidence of pre-cutting or explosive severance of beans at any point during debris removal activities.'


2.3 Near-Symmetrical Collapse of WTC 7



The collapse of WTC 7 building, which was not hit by planes is one of the more enduring mysteries of 9/11. The counter-orthodoxy argues that a 47 story steel-framed building with small falling debris damage and low-grade fires burning for only 7 hours should not have collapsed. Suspicions are also fuelled by the fact that NIST has yet to complete its report on the building. Jones draws attention to one of the features of its collapse:



Jones: &#8220;WTC 7 collapsed rapidly and nearly-straight-down symmetrically -- even though fires were randomly scattered in the building. WTC 7 fell about seven hours after the Towers collapsed, even though no major persistent fires were visible (considerable dark smoke was seen). &#8221;



I believe that the near-symmetry of the WTC 7 collapse is overstated in the CD theories. An aerial view of the site after collapse shows the north fa&#231;ade of the building neatly folded on top of the rubble, suggesting that the front of the building, which had received severe damage, collapsed ahead of the rear, which had no damage. As the front of the building fell, it pulled the rear down on top of the debris. It is also rather vague to say that &#8220;no major persistent fires were visible&#8221; &#8211; such a statement does not lead to quantifiable assessments of thermal heat production or temperatures. The photograph below shows the &#8216;considerable dark smoke&#8217; pouring from the building: is this not due to a major fire?





I am indebted to the Debunking 911 site for this image, and recommend reading the entire page devoted to this issue: Debunking 9/11 Conspiracy Theories and Controlled Demolition - World Trade Center 7, Building 7. The face of the building (WTC 7 is the pink-coloured one) from which smoke is pouring is the south face damaged by debris falling from WTC 1. (I recommend watching the video of WTC 7 burning, available on the same webpage.)



But in any case why should we accept from Jones that &#8220;no major persistent fires were visible&#8221; even if this has become the mantra of the counter-orthodoxy? Wouldn&#8217;t the eye-witness testimony of experienced New York firefighters count for more?



Captain Chris Boyle (Engine 94) with 18 years of service with the FDNY gave this interview:

Firehouse: Did that chief give an assignment to go to building 7?

Boyle: He gave out an assignment. I didn&#8217;t know exactly what it was, but he told the chief that we were heading down to the site.

&#8230; We went one block north over to Greenwich and then headed south. There was an engine company there, right at the corner. It was right underneath building 7 and it was still burning at the time. They had a hose in operation, but you could tell there was no pressure. It was barely making it across the street. Building 6 was fully involved and it was hitting the sidewalk across the street. I told the guys to wait up.

A little north of Vesey I said, we&#8217;ll go down, let&#8217;s see what&#8217;s going on. A couple of the other officers and I were going to see what was going on. We were told to go to Greenwich and Vesey and see what&#8217;s going on. So we go there and on the north and east side of 7 it didn&#8217;t look like there was any damage at all, but then you looked on the south side of 7 there had to be a hole 20 stories tall in the building, with fire on several floors. Debris was falling down on the building and it didn&#8217;t look good.

But they had a hoseline operating. Like I said, it was hitting the sidewalk across the street, but eventually they pulled back too. Then we received an order from Fellini, we&#8217;re going to make a move on 7. That was the first time really my stomach tightened up because the building didn&#8217;t look good. I was figuring probably the standpipe systems were shot. There was no hydrant pressure. I wasn&#8217;t really keen on the idea. Then this other officer I&#8217;m standing next to said, that building doesn&#8217;t look straight. So I&#8217;m standing there. I&#8217;m looking at the building. It didn&#8217;t look right, but, well, we&#8217;ll go in, we&#8217;ll see.

So we gathered up rollups and most of us had masks at that time. We headed toward 7. And just around we were about a hundred yards away and Butch Brandies came running up. He said forget it, nobody&#8217;s going into 7, there&#8217;s creaking, there are noises coming out of there, so we just stopped. And probably about 10 minutes after that, Visconti, he was on West Street, and I guess he had another report of further damage either in some basements and things like that, so Visconti said nobody goes into 7, so that was the final thing and that was abandoned.

Firehouse: When you looked at the south side, how close were you to the base of that side?

Boyle: I was standing right next to the building, probably right next to it.

Firehouse: When you had fire on the 20 floors, was it in one window or many?

Boyle: There was a huge gaping hole and it was scattered throughout there. It was a huge hole. I would say it was probably about a third of it, right in the middle of it. And so after Visconti came down and said nobody goes in 7, we said all right, we&#8217;ll head back to the command post. We lost touch with him. I never saw him again that day.

Firehouse.com's 9-11 Coverage: News 9/9/02 - WTC: This Is Their Story



Here is an extract from the testimony of Deputy Chief Peter Hayden, who had 33 years service in Division 1 to his credit:



Firehouse: Other people tell me that there were a lot of firefighters in the street who were visible, and they put out traffic cones to mark them off?



Hayden: Yeah. There was enough there and we were marking off. There were a lot of damaged apparatus there that were covered. We tried to get searches in those areas. By now, this is going on into the afternoon, and we were concerned about additional collapse, not only of the Marriott, because there was a good portion of the Marriott still standing, but also we were pretty sure that 7 World Trade Center would collapse. Early on, we saw a bulge in the southwest corner between floors 10 and 13, and we had put a transit on that and we were pretty sure she was going to collapse. You actually could see there was a visible bulge, it ran up about three floors. It came down about 5 o&#8217;clock in the afternoon, but by about 2 o&#8217;clock in the afternoon we realized this thing was going to collapse.



Firehouse: Was there heavy fire in there right away?



Hayden: No, not right away, and that&#8217;s probably why it stood for so long because it took a while for that fire to develop. It was a heavy body of fire in there and then we didn&#8217;t make any attempt to fight it. That was just one of those wars we were just going to lose. We were concerned about the collapse of a 47-story building there. We were worried about additional collapse there of what was remaining standing of the towers and the Marriott, so we started pulling the people back after a couple of hours of surface removal and searches along the surface of the debris. We started to pull guys back because we were concerned for their safety.



Firehouse.com's 9-11 Coverage: News 9/9/02 - WTC: This Is Their Story



I believe that the testimony of experienced fireman ought to give most sober-minded people very serious doubt about the CD hypothesis, in particular the account of the sagging of the building prior to collapse, the assertion by Hayden that it was a heavy fire, and the testimony regarding lack of water pressure to fight the blaze.



Boyle&#8217;s report suggested that the debris caused a huge gash of twenty storeys in that face, which would allow for the flow of air to the fires simply unprecedented in fires in similar buildings.



All the evidence suggests that WTC 7 was unique in the history of fire-fighting because (a) structural damage was extensive, (b) vast openings in the south face allowing unimpeded airflow, (c) water mains had been severed by the collapse of the Towers, and hence almost no water was available to the Fire Service, and (d) the Fire Service had anyway made the eminently reasonable policy decision that their priority was to save lives not buildings, so it burned for 7 hours virtually unattended. Also, the bulging of the building prior to collapse is also prime evidence against the CD theory, because controlled demolition never produces such bulges.



In this section Jones also wants to argue that the fine rubble produced in the WTC 7 collapse is evidence of explosives:



Jones: By contrast, concrete floors in the Twin Towers and WTC 7 were pulverized to dust -- as is common in controlled demolitions using explosives.



But we have already pointed out that concrete floors, if they are pulverised to dust in controlled demolition, are pulverised due to gravity, not explosives. This is a core mistake repeated by Jones and other CD theorists.

Brent Blanchard deals with WTC 7 in section 7 of his paper. He refutes the claim that the owner of WTC 7 had any role in its collapse, and also says: 'Any detonation of explosives within WTC 7 would have been detected by multiple seismographs monitoring ground vibration in the general area. No such telltale "spike" or vibratory anomaly was detected by any recording instrument.' I will return to the issue of seismic data in section 3.3.


2.4 No Previous Skyscraper Collapse Due to Fires



This is one of the leading arguments in favour of the CD hypothesis, and the counter argument states that no previous skyscraper had been hit by an airliner. In the case of WTC7 the counter argument goes that it (a) it suffered severe structural damage from falling debris, and (b) fires raged for 7 hours in it, with no significant fire-abatement effort. In the differing cases of the towers and building 7, the IF theory has to show that structural damage (including insulation displacement) plus fire is an adequate account. Hence the CD theorists must present evidence to show that the IF account is inadequate, by denying the magnitude of both the structural damage, and the intensity of the fires. Too much of the argument either way on this issue is mere opinion, so the best science here is to return to issues that have a clearer empirical basis.


2.5 Squib-timing during the Collapse of WTC 7



For many CD theorists, the ejection of puffs of smoke and other debris during collapse is a sure sign of the use of explosives.



Jones: &#8220;Horizontal puffs of smoke and debris are observed emerging from WTC-7 on upper floors, in regular sequence, just as the building starts to collapse. (The reader may wish to view the close-up video clip again.) The upper floors have evidently not moved relative to one another yet, from what one can observe from the videos. In addition, the timing between the puffs is less than 0.2 seconds so air-expulsion due to collapsing floors (see Chertoff, 2005) is evidently excluded. Free-fall time for a floor to fall down to the next floor is significantly longer than 0.2 seconds: the equation for free fall, y = &#189; gt2, yields a little over 0.6 seconds, as this is near the initiation of the collapse.&#8221;



Jones is referring to videos of WTC 7 collapse which show dark markings on the right of the top of the building, as in the 2nd image below. They are nothing like as regular in sequence as he proposes, and he uses video footage which focuses in just on the top right instead of the whole building. In the two frames below it is clear that dark markings appear erratically over the building, and in no sequence that could possibly suggest controlled demolition.





Descent initiated


In descent: note the appearance of small dark patches across the building.





The Debunking 911 site devotes a page to this at Debunking 9/11 Conspiracy Theories and Controlled Demolition - Squibs where it is suggested that the specific locations of the dark markings Jones refers to is in fact due to impact damage on that corner of the building:





I am grateful to the Debunking 911 site for this image, and the suggestion that we are looking at damaged panels flapping about, rather than at &#8216;squibs.&#8217; The photograph of the damage to WTC 7 so high on the building also helps us understand the extent of the damage to the whole of the south fa&#231;ade, which we do not apparently have other photographic records of.



In the video the upper ten or so storeys are moving downwards as one, so air-expulsion originating from within these floors is ruled out, but not because of the timings Jones cites. Instead, it is obvious that if there was air-expulsion of debris and fine dust would be generated by the pancaking taking place far below, rather than within these levels. The &#8216;puffs&#8217;, travelling up the ten or so storeys visible in the video could not come from the upper storeys, but could come from pressure build up below expelling material up a shaft or stairwell, and out horizontally where there were open corridors or other relatively unimpeded flow ways, or, more simply, as Debunking 911 says, causing previously damaged panels to flap about. It would be impossible to put the timing constraints that Jones suggests on these &#8216;squibs&#8217; because one would need a precise hydrodynamic model of the overpressures working their way through the collapsing structure.



Jones: &#8220;However, the presence of such &#8220;squibs&#8221; proceeding up the side of the building is common when pre-positioned explosives are used, as can be observed at ImplosionWorld.com The same site shows that rapid timing between explosive squibs is also common.&#8221;



Jones is right to say that &#8220;rapid timing between explosive squibs is also common&#8221; (often down to microseconds) but he fails to notice the much bigger timing issue in controlled demolition. Any detonations on upper floors are designed, not to bring the building down, or accelerate its progress, but to &#8216;teach&#8217; the building how to collapse, once it starts descending. As such, the explosions on upper floors take place in the fractions of seconds prior to the main descent of the building, not during it.



Jones also appears to believe that such &#8216;squibs&#8217; running up a building are common, as if it confirms for him that demolition proceeds by progressively cutting away floors in a progressive upward fashion. This is simply not true, necessary, or possible in conventional explosive demolition. Jones would also need to account for the overall pattern of dark patches appearing across the building as it descended, which he ignores.



Jones: &#8220;Thus, squibs as observed during the collapse of WTC 7 going up the side of the building in rapid sequence provide additional significant evidence for the use of pre-placed explosives.&#8221;



Even by using the term &#8216;squib&#8217; Jones has pre-judged the hypothesis, because &#8216;squib&#8217; means firework or explosive. The puffs of smoke are however no evidence of controlled demolition, because controlled demolition simply does not require explosive charges to go off at this point, and in such a sequence. The timing and sequence can, however, be explained by the ejection of debris in the crumple zone at the base of the building, and the huge build-up of pressure forcing the material upwards through shafts (or new cavities emerging during collapse) and being forced out as the material progressively shoots upwards. Alternatively the &#8216;squibs&#8217; are merely damaged panels flapping about, perhaps moving due to pneumatic pressures from pancaking.



The supposed existence of &#8216;squibs&#8217; in the Twin Towers is also cited as evidence for the CD theory, but, as Debunking 911points out on its squib page, the ejecta generally increase in intensity over time, as one would expect from pneumatic effects. Explosives are defined by the fact of the incredibly short time in which their blast wave spreads, quite unlike the spurts in the Twin Tower videos.



Returning to WTC 7, Popular Mechanics interviewed a NIST official and reported as follows:



NIST's Sunder tells PM. "On about a third of the face to the center and to the bottom--approximately 10 stories--about 25 percent of the depth of the building was scooped out." NIST also discovered previously undocumented damage to WTC 7's upper stories and its southwest corner.



NIST investigators believe a combination of intense fire and severe structural damage contributed to the collapse, though assigning the exact proportion requires more research. But NIST's analysis suggests the fall of WTC 7 was an example of "progressive collapse," a process in which the failure of parts of a structure ultimately creates strains that cause the entire building to come down. Videos of the fall of WTC 7 show cracks, or "kinks," in the building's facade just before the two penthouses disappeared into the structure, one after the other. The entire building fell in on itself, with the slumping east side of the structure pulling down the west side in a diagonal collapse.



According to NIST, there was one primary reason for the building's failure: In an unusual design, the columns near the visible kinks were carrying exceptionally large loads, roughly 2000 sq. ft. of floor area for each floor. "What our preliminary analysis has shown is that if you take out just one column on one of the lower floors," Sunder notes, "it could cause a vertical progression of collapse so that the entire section comes down."



There are two other possible contributing factors still under investigation: First, trusses on the fifth and seventh floors were designed to transfer loads from one set of columns to another. With columns on the south face apparently damaged, high stresses would likely have been communicated to columns on the building's other faces, thereby exceeding their load-bearing capacities.



Second, a fifth-floor fire burned for up to 7 hours. "There was no firefighting in WTC 7," Sunder says. Investigators believe the fire was fed by tanks of diesel fuel that many tenants used to run emergency generators. Most tanks throughout the building were fairly small, but a generator on the fifth floor was connected to a large tank in the basement via a pressurized line. Says Sunder: "Our current working hypothesis is that this pressurized line was supplying fuel [to the fire] for a long period of time."



This text is available at: Debunking the 9/11 Myths: Special Report - Popular Mechanics. Note that we are, as of August 2006, still awaiting the NIST report on WTC 7: it may well throw up new data.

Brent Blanchard devotes section 3 of his paper to refuting the claim that plumes indicate explosives, pointing out that it is air-expulsion that causes the visible sitings of plumes etc.


2.6 Early Drop of North Tower Antenna



I am particularly puzzled why Jones thinks that the &#8216;early&#8217; drop of the North Tower antenna points to controlled demolition:



Jones: &#8220;The building stood for more than an hour and a half. Videos of the north tower's collapse appear to show that its television antenna began to drop a fraction of a second before the rest of the building. The observations suggest that the building's steel core somehow gave way first&#8230; (Glanz and Lipton, 2002; emphasis added)

But how? What caused the 47 enormous steel core columns of this building which supported the antenna to evidently give way nearly simultaneously, if not cutter charges?&#8221;



Jones commits, not so much an error of science here, as an error in logic. The IF theory requires the &#8216;47 enormous steel core columns&#8217; of the building to give way first, due to structural damage and fire. The CD theory requires that cutter charges do the job. But the early drop of the North Tower antenna is consistent with either theory. Therefore Jones cannot claim that this phenomenon supports only the CD theory. It is also not clear why he wants to call it an &#8216;anomaly&#8217; other than perhaps to discredit the IF theory by stealth.



When records from east and west vantage points were viewed, it was apparent that the building section above the impact area tilted to the south as the building collapsed. (NIST, 2005)



Jones: However, we find no quantitative analysis in the report which shows that this tilting of the building section was sufficient to account for the large apparent drop of the antenna as seen from the north, or that this building-section-tilting occurred before the apparent antenna drop. Furthermore, the FEMA investigators also reviewed "videotape recordings of the collapse taken from various angles" yet came to the sense that "collapse began with one or more failures in the central core area of the building." (FEMA, 2002) Quantitative analysis needs to be done and shown to resolve the issue.



All that Jones is doing in this statement is to re-iterate the challenge to the IF theory to account for the collapse of the central columns. The early descent of the antenna lends no additional support to the CD theory whatsoever, though at the same time it does not contradict it. Put more simply: it is a red herring.


2.7 Eyewitness Accounts of Flashes and Loud Explosions



The CD theorists draw a lot on eyewitness testimony from non-experts.



Jones: &#8216;Multiple loud explosions in rapid sequence were heard and reported by numerous observers in and near the WTC Towers, consistent with explosive demolition. Firemen and others described flashes and explosions in upper floors near where the plane entered, and in lower floors of WTC 2 just prior to its collapse, far below the region where the plane had struck the tower (Dwyer, 2005). For instance, at the start of the collapse of the South Tower a Fox News anchor reported: &#8220;There is an explosion at the base of the building&#8230; white smoke from the bottom&#8230; something happened at the base of the building! Then another explosion.&#8221; (De Grand Pre, 2002, emphasis added.)&#8217;



When Jones says that &#8216;explosions&#8217; were heard, he is, like with the word &#8216;squib,&#8217; using language that implies a pre-judgement. A more neutral and scientific term would be &#8216;loud report&#8217; possibly consistent with explosions. To say that these reports were &#8216;multiple loud explosions consistent with explosive demolition&#8217; (my italics) is to further lead the reader. But has Jones taken the trouble to play the interviewees audio tapes of controlled demolition to see how closely the reports resemble the detonation of typical explosives used in demolition? Such explosives detonate with a signature &#8216;crack&#8217; quite different to the loud reports that can be generated from a host of other phenomenon. Aviation fuel, spilling through the building and building up pockets of fuel-air mixtures in confined spaces, would detonate as a stray spark reached them from the fires above. It is known that floors collapsed prior to the main descent of the buildings: the sounds of steel buckling and breaking, and of concrete smashing onto lower floors, would all emit loud reports. Many other objects and devices commonly found in skyscrapers would explode when exposed to fires of up to an hour and a half: has Jones made any study of this in connection with conventional fires?



The issue of loud reports issuing from ground or lower floors is in fact inconsistent with the CD theory. This is because the building collapsed from the top, not the bottom, and hence the CD theory itself would rule out the placing of charges at the lower floors. The CD theory of the twin towers collapse has to be a theory of top-down demolition. This is recognised by 911 Review (which promotes the CD theory) in a webpage called &#8220;DISTRACTION: 'Explosions in the Towers' Basements Preceded Collapses'&#8221; The pages states:



The idea that powerful explosions in the Towers' basements initiated the collapses is not supported by credible evidence, but is contradicted by large bodies of evidence. We note:



&#183; The conclusions that seismic spikes preceded the collapses is based on flawed analysis.

&#183; The body photographic and video evidence contradicts the idea that large explosions in the Towers' bases precipitated the collapses.

&#183; The testimonies of emergency responders do not include descriptions of large-scale explosions low in the towers preceding the descent of the dust clouds. (9-11 Review: DISTRACTION: 'Explosions in the Towers' Basements Preceded Collapses')



Brent Blanchard devotes section 4 of his paper to refuting the claim that eye-witness heard the sound of explosives. He says: 'Simply put, there are countless causes of sharp, loud noices that have no relation to explosives. The only scientifically legitimate way to ascertain if explosives were used is to cross reference the fundamental characteristics of an explosive detonation with independed ground vibration data recorded near Ground Zero on 9/11.' I&#8217;ll return to the issue of seismic spikes, and why these eliminate the possibility of explosives, in section 3.3.


2.8 Ejection of Steel Beams and Debris-plumes from the Towers



Jones: &#8220;The horizontal ejection of structural steel members for hundreds of feet and the pulverization of concrete to flour-like powder, observed clearly in the collapses of the WTC towers, provide further evidence for the use of explosives &#8211; as well-explained in Twin Towers Demolition. (See also, Griffin, 2004, chapter 2.) The observed plumes or "squibs" are far below the pulverization region and therefore deserving of particular attention. They appear much like the plumes observed in ImplosionWorld.com (e.g., the controlled demolition of the Southwark Towers).&#8221;



The CD hypothesis is somewhat self-contradictory here, in that much is made of the collapse of the towers into a small area as evidence of &#8216;skilled&#8217; controlled demolition. On the other hand the &#8216;horizontal ejection of steel members&#8217; which spread the debris well beyond the footprint of the building is also cited as evidence of CD. But careful observation of controlled demolition shows that much material is ejected horizontally at the point of pancaking, i.e. in the crumple zone. This ejection is not caused by explosion but by the huge pneumatic overpressures of the descending building. The Towers, unusually, had a crumple zone very high up, making the horizontal ejection of material uniquely visible. While explosives could have caused this, so could the pneumatic pressure of descent of the upper floors. In WTC 1 there were between 12 and 18 stories collapsing onto the impact area between floors 94 and 98, while in WTC 2 there were between 26 and 32 stories collapsing onto the impact area between floors 78 and 84. If one views the base of a 12-18 story building or a 26-32 story building being demolition in a traditional bottom-up demolition, vast amounts of debris are ejected at this point. (To put it in perspective the tallest building ever demolished by controlled explosions is 25 storeys.)



The issue of pulverisation is also crucially misunderstood. By far of the bulk of pulverisation that takes places in a controlled demolition is not due to explosives, but due to the free-fall descent of the building.



The plumes referred to by Jones (called &#8216;mysterious&#8217; in the caption he provides next to the photo illustrating them) could be caused by explosives. Equally the enormous pneumatic overpressures caused by the collapse above them (involving a greater mass at this point in the descent than in any controlled demolition in history) could easily have forced material ahead of them to blow out of any weakest route made possible by the combination of vertical shafts and horizontal corridors.



All of the observed phenomenon, as Jones points out, could be the result of explosions. But equally, all of them are consistent with gravity-powered collapse, once begun. It is also important to note that much of the dust produced would have been from plaster, a material that disintegrates far easier than concrete. The NIST findings confirm that gypsum (the main ingredient of plaster) was widely found in the debris.


2.9 Rapid Collapses and Conservation of Momentum and Energy



Jones: &#8220;How do the upper floors fall so quickly, then, and still conserve momentum and energy in the collapsing buildings? The contradiction is ignored by FEMA, NIST and 9-11 Commission reports where conservation of energy and momentum and the fall-times were not analyzed. The paradox is easily resolved by the explosive demolition hypothesis, whereby explosives quickly remove lower-floor material including steel support columns and allow near free-fall-speed collapses (Harris, 2000).&#8221;



To many people the apparent collapse of the buildings at &#8216;near free-fall-speed&#8217; is one of the most compelling arguments in favour of the CD theory. However it is also the most easily dealt with on scientific grounds. The fact is that the near free-fall-speed of collapse of buildings in controlled demolition is entirely due to gravity, and not to explosives. The question of course remains, how come that buildings, impeded by their intact lower floors, collapse so fast? (Though of course, this is not a question with any direct relevance to 9/11.) Put this way, the question conveys the essential fact of controlled demolition: that the only floors effectively &#8216;removed&#8217; from the building are the lowest. (Further charges are placed in the building if and only if it is necessary to guide its fall in a certain way, for example to collapse a building into its footprint.) In a 20-story building, for example, the bottom floor or floors is extensively rigged with explosive, to remove its load-bearing capability. The remaining 18-odd storeys pancake into the region of the destroyed floor, one at a time, raising exactly the same question as to how is it that this process can take place so quickly? The same question applies to conventional demolition, and to the Tower buildings. The difference is that the pancaking occurs high in the Twin Towers (&#8216;top-down pancaking&#8217;), and at the base of WTC 7 (&#8216;bottom-up pancaking&#8217;). In the usual bottom-up process each floor impedes the process of collapse through its structural rigidity, just as much as one would expect in the top-down processes in the Towers. Although no text-book account is available which might give a simple answer to the issue of the speed of gravitational collapse of buildings, one might draw on the analogy of a hydraulic press compressing, say, a car body shell. The car body shell may seem strong enough to withstand everyday loadings, but, when it takes the hit of a high-powered press, it collapses with astonishing speed. 18 storeys of a big building, moving even rather sedately as they would at the onset of collapse, probably outstrip the forces of even the biggest hydraulic press ever built.



It seems that all the proponents of the CD theory state the case, like Jones above, along the lines: &#8220;The paradox is easily resolved by the explosive demolition hypothesis, whereby explosives quickly remove lower-floor material including steel support columns and allow near free-fall-speed collapses.&#8221; This is simply unscientific; not corresponding to the reality of how controlled demolition is carried out. Returning to our example of the collapse of a 20-story building, there is simply no need to explode each floor, and such explosions are certainly not the explanation of why buildings fall so fast in controlled demolition. All the calculations produced by the CD theorists, designed to prove their theory, are based on the wrong premise, that explosions accelerate the descent. They don&#8217;t: it is purely gravity that does it.



Jones: &#8220;We observe that approximately 30 upper floors begin to rotate as a block, to the south and east. They begin to topple over, not fall straight down. The torque due to gravity on this block is enormous, as is its angular momentum. But then &#8211; and this I&#8217;m still puzzling over &#8211; this block turned mostly to powder in mid-air! How can we understand this strange behavior, without explosives?&#8221;



Jones seems to believe that a 30-story section of the building was &#8220;turned mostly to powder in mid-air,&#8221; through the use of explosives. He ignores the fact that large sections of the building, such as this, did fall, and were responsible for destroying or partly destroying other WTC buildings. Although considerable disintegration of the 30-story block was inevitable as it impacted on the rest of the South Tower, the bulk of the pulverisation would have been on impact on the WTC complex. Here is a photo of a large chunk of WTC 2 falling onto WTC 3, which was almost totally destroyed by debris falling from the Towers. This fragment shows a different orientation to the section described by Jones, which suggests that angular momentum was conserved.







The next photo shows the destruction wreaked on WTC 3 by debris falling from WTC 2.





This photo was taken after the collapse of WTC2 and before the collapse of WTC1, half an hour later. It must surely lay to rest the idea that the Towers were blasted to bits in mid-air. Only large chunks of falling debris, as shown in the previous photo, could cause this kind of destruction.



But anyway, to truly explode a 30 story building in mid-air would be an astonishing feat of pyrotechnics, and would also beg the question: why bother? But if Jones is serious, the estimate of the amount of explosives required, in metric tonnes, would be staggering, plus the almost insurmountable feat of triggering them at this point in the collapse. Jones, in section 1, estimates &#8220;Roughly 2,000 pounds of RDX-grade linear-shaped charges&#8221; would be sufficient to bring the building down (note: around one metric tonne). He says: &#8220;The estimate is based on the amount of explosives used in controlled demolitions in the past and the size of the buildings.&#8221; He doesn&#8217;t point out however that this quantity of explosives merely cuts the building up for descent, and that it is gravity that does the work of pulverising. The amount of RDX would go up by factors of hundreds to achieve what Jones imagines for the top 30 storeys, and of course is multiplied again if the CD theory demands that explosives account for all the pulverisation. Even if hundreds or thousands of tonnes of RDX could be insinuated into the building without anyone noticing, the question again would be: what on earth for?



It is worth showing some pictures here that show how parts of the North Tower took much longer than free-fall speeds to collapse:







This shard or &#8216;spire&#8217; of the North Tower remained standing some 15s after the main collapse


In this photo it begins to collapse


In this photo vertical columns can be seen breaking away, demonstrating how, once collapse began, the steel columns peeled away from the structure.



The Debunking 911 site devotes a page to demonstrating that the buildings did not fall at free-fall speeds, and is worth looking at: Debunking 9/11 Conspiracy Theories and Controlled Demolition - Free Fall.


2.10 Controlled Demolition &#8220;Implosions&#8221; Require Skill



The photos above show that Jones is exaggerating &#8216;straight-down and complete collapses&#8217;:



Jones: &#8220;The occurrence of nearly symmetrical, straight-down and complete collapses of the WTC 7 and the Towers is particularly upsetting to the &#8220;official&#8221; theory that random fires plus damage caused all these collapses. Even with high-level cutting charges, achieving such results requires a great deal of pre-planning and expertise.&#8221;



This image sequence should destroy the myth that the Towers collapsed symmetrically or straight-down:







1


2


3





4


5


6



In frame 2 of the video sequence we can see a large chunk of WTC 2 falling down to its left. In frame 3 a much larger part of the building, most likely the 30-story section above the impact zone, clearly rotating away from the building, reaching &#8211; I would estimate &#8211; something like one-third of the Tower height away from the Tower. In the video it is clearly visible rotating away from the building, fully conserving its angular momentum. One has to ask why Jones ignores clear evidence like this, going back to the claims he makes in the previous section that this large chunk turned to powder in mid air. From the video it is clear that this section of the building is rotating as a relatively intact unit until we can no longer see its further progress, due to the dust cloud.



Jones is highlighting a common perception, that the &#8220;nearly symmetrical, straight-down and complete collapses of the WTC 7 and the Towers&#8221; is the strongest evidence for controlled demolition. The Twin Towers present a very different case to the WTC 7 building, and their collapse is the most indelibly printed on the public imagination. However, they are most easily dealt with. Their collapse is like no controlled demolition ever carried out in the world. This is because they collapsed in a top-down fashion. Jones inadvertently confirms this when he quotes Harris: &#8220;Generally speaking, blasters will explode the major support columns on the lower floors first and then a few upper stories,&#8221; and Mark Loizeaux, president of Controlled Demolition, Inc: &#8220;If I were to bring the towers down, I would put explosives in the basement to get the weight of the building to help collapse the structure.&#8221; But it is absolutely clear from the way that the twin towers collapsed that there was no collapse from the lower floors or basement of the building: collapse began at the impacted floors and proceeded top-down.



Jones makes no acknowledgement of this fact, confusing the issue further by stating:



&#8220;Just right &#8211; &#8220;explosives in the basement&#8221; agrees with eyewitness reports of pre-collapse explosions down low in the buildings (point 7 above). Also, this would be the way to effectively sever the support columns, consistent with both the apparent initial drop of the communication tower (WTC Tower 1) and the &#8220;kink&#8221; in the middle of WTC 7 as its collapse began.&#8221;



This is patently absurd. Jones imagines that explosive detonations were carried out low in the Tower buildings, severing the support columns, which then somehow &#8216;slid&#8217; through the building while the outer structure remained in place, but achieving the initial drop of the North Tower antenna. He imagines that severed columns in the base of the building would somehow cause a collapse at floors 80 to 90 with no movement of the building in between. Any examination of the videos of collapse in conventional demolition show that once the lower columns are severed, collapse begins at the bottom of the building.



The fact is that the Twin Towers began their collapse at the levels where the planes impacted, and that the unique top-down collapse, never seen before in the entire history of the demolition of tall buildings, ensured that they fell (very) approximately within their footprint, rather than toppling. In fact the spread of debris was far greater than would be acceptable in any implosion, but then, no building of this height has ever been demolished by explosives (a building like this would be dismantled). If Jones requires a controlled demolition theory, then the explosives would have to have severed columns at the level of aeroplane impact, not at the ground level.



The WTC 7 building is a different case, which does resemble controlled demolition, in some aspects only, in particular that it follows a conventional bottom-up collapse. But the CD theory never recognises the following facts:



1. No building ever suffered both impact damage and fire on the scale of WTC 7, allowing unimpeded air supply not possible to fires in the absence of structural damage

2. No building ever burned for 7 hours with such a complete absence of fire-abatement effort, made impossible by the severing of water mains, and the extraordinary demands on the city&#8217;s fire department.



The initial &#8216;kink&#8217; that Jones refers to is consistent with a localised collapse in the front centre of the building, consistent with the structural damage to the front of the building and the huge supply of air available.


2.11 Steel Column Temperatures of 800&#176;C Needed: A Problem in the Argument of Bazant and Zhou



Jones: &#8220;Correct &#8211; the WTC Towers were designed to withstand forces caused by large commercial aircraft &#8211; we can agree on that. MIT&#8217;s Thomas Eagar also concurs &#8220;because the number of columns lost on the initial impact was not large and the loads were shifted to remaining columns in this highly redundant structure&#8221; (Eagar and Musso, 2001).&#8221;



Jones is stating here a widely circulated opinion: that the Towers were designed to withstand the impact of a commercial plane. But the CD theorists consistently overlook two factors here. Firstly that the designers had in mind an aircraft coming in to land at New York airport, at speeds of around 180 mph (according to the FEMA report, page 1:17). But the aircraft hit the towers at an average of nearly three times that speed. Given that the impact damage hinges on the kinetic energy of the projectile, which rises with the square of speed, the planes hit the Twin Towers with nearly nine times the impact anticipated. (Note that the NIST report - on page 6 - contradicts this argument by stating that the Towers were designed for a 600 mph impact. I would be pleased to hear from anyone who can settle this discrepancy one way or the other.) Secondly, design is an art not a science: the Titanic was designed not to sink; the space shuttle was designed not to explode on takeoff, and designed not to break up on re-entry. Etc.



Jones: &#8220;They do NOT explain how steel-column temperatures above 800oC were achieved near-simultaneously due to burning office materials. NIST notes that office materials in an area burn for about 15-20 minutes, then are consumed away (NIST, 2005, pp. 117, 179). This is evidently not long enough to raise steel column temperatures above 800oC as required in the Bazant & Zhou model, given the enormous heat sinks of the structures. And to have three buildings completely collapse due to this unlikely mechanism on the same day strains credulity.&#8221;



Jones is presenting perhaps the core issue that requires explanation: the high temperatures in all three fires. What the CD theorists consistently attempt to promote however is that the fires in the three buildings were standard &#8216;office fires&#8217; which should not have led to collapse. This is simply not the case.



In the case of the Twin Towers the impact and presence of the planes ensures that the structural damage and ensuing fires were like nothing previously encountered. Some images are essential here to convey the magnitude of the situation.







These diagrams require that any serious thinker on this subject consider the impact of the planes: AA flight 11 crashed into north face of North tower (WTC1), between floors 94 and 98, at 470 mph, and UA 175 crashes into south face of the South Tower (WCT2), between floors 78 and 84, at 590 mph. One CD theorist compared these impacts to a &#8216;pencil going through a mosquito net,&#8217; part, it seems, of a consistent attempt to downplay their importance. Here is a visualisation of the impact on WTC2:















Fig. 3 Frames from a visualisation of WTC2 impact (source: Debunking 911 Conpiracy Theories and Controlled Demolition Homepage)



As the FEMA report points out, UA 175 crashed into the WCT2 in a direction to make its passage towards the central core of the building much shorter. Here is a visualisation of the impact damage:





Fig. 4 Visualisation of impact damage on WCT 2 (source: Debunking 911 Conpiracy Theories and Controlled Demolition Homepage)



While no-one can verify the details of such a visualisation, it would be at the very least likely that a significant number of core columns would have been damaged by the impact alone, prior to any weakening by fire.



A passenger jet can crash and initiate intense fires, even, apparently, without its aviation fuel igniting, as in this example of an Air France accident:









Fig. 5 Air France Airbus 340 flight 358 crash (source: Debunking 911 Conpiracy Theories and Controlled Demolition Homepage, see also Air France Flight 358 - Wikipedia, the free encyclopedia)



One can see that the wings of the aircraft, where the fuel is kept, did not catch fire. The intense blaze and utter devastation of the fuselage was due only to friction on impact and combustibles within the fuselage. Notice the intense yellow-orange base of the fire behind the wing in the first picture: easily hot enough to melt aluminium at 650 degrees centigrade. If one now imagines this crash compressed into the impact zones in the Towers, plus around 10,000 gallons each of aviation fuel, then how can one conceive of the resulting conflagration as a mere &#8216;office fire?&#8217;



Returning to the impact of the planes, one can calculate their kinetic energy at the time of impact to be about 4.415 x 1009 Joules (equivalent 4 million one bar electric fires operating for one second). This energy alone is capable of melting four metric tonnes of steel, though of course no one would suggest that the kinetic energy of a plane would be converted 100% into heat and focussed on the steel. The energy would appear as a mixture of fracture energy, sound energy, heat energy and even a small amount of light. But the point seems to be lost on the CD theorists: that impact energy was substantial, and that a significant proportion would be converted to heat energy, never mind the combustibles on the plane and the aviation fuel.



To put it another way: how can one ignore 150 metric tonnes of aircraft impacting at speeds between 470 and 590 mph, when skidding off a runway at perhaps only 100 mph caused a complete conflagration in Air France 385? And when it received prompt attention from the airport fire brigade? (They were hampered by heavy rain which diluted the millions of gallons of foam deployed on the blaze, and it took 12 hours to put out.)



This is another key issue that the CD theorists ignore: the lack of fire abatement provision that would be normal in a conventional &#8216;office fire.&#8217; The 9/11 Commission Report details the decision made early in the events that the fire department response would be rescue only and not fire fighting (p. 290-291). This decision was made on the grounds of the magnitude of the emergency at that point, and the imperative to rescue thousands of office workers. Also clear is that the fire department had no idea whether any water supply was still functional.



Summary

In the 17-minute period between 8:46 and 9:03 A.M. on September 11, New York City and the Port Authority of New York and New Jersey had mobilized the largest rescue operation in the city's history. Well over a thousand first responders had been deployed, an evacuation had begun, and the critical decision that the fire could not be fought had been made. (CR p.293, my italics)



This is a good point to raise a pet theory of mine (and it is only a theory): that the many tons of aluminium in the planes may have contributed to the fire and the high temperatures, by igniting. Normally, aluminium does not burn in air, due to the very tough layer of oxide that rapidly forms on its surface. However the Air France jet would have involved abnormal conditions in which the aluminium was effectively ground against concrete at 100 mph, bearing the weight of the plane. The friction involved was enormous, and sufficient to bring the plane to rest, and may have provided, along with an 100 mph oxygen supply, the conditions for the aluminium to burn. The impact conditions of the planes entering the Twin Towers was likewise far from normal, and even if only a few tons of the aluminium burned, it would have produced very high temperatures indeed and a large heat input to the conflagration. It will be interesting to see, when the Air France crash report is produced, whether it shows (a) that indeed little or no aviation fuel contributed to the fire, and (b) whether the aluminium of the hull burned rather than just melted.


2.12 Problems in the NIST Report: Inadequate Steel Temperatures and Tweaked Models



Jones: &#8220;However, I along with others challenge NIST&#8217;s collapse theory. NIST maintains that all three building collapses were fire-initiated despite the observations above, particularly the fact that fire endurance tests with actual models did not result in collapse. &#8230; I agree with these pointed objections, particularly that the &#8220;response of the whole frame&#8221; of each building should be considered, especially heat transport to the whole frame from localized fires, and that the &#8220;core columns cannot pull the exterior columns in via the floor.&#8221; (Lane and Lamont, 2005)&#8221;



From a scientific point of view these are some of the most difficult issues to deal with, but Jones misrepresents NIST here when he says &#8220;NIST maintains that all three building collapses were fire-initiated.&#8221; NIST is careful to point out that the collapse resulted from three factors, not the single factor of fire. The two additional factors, apart from fire were (1) structural damage due to impact, and (b) the damage to insulation caused by the impact. NIST say: &#8220;In the absence of structural and insulation damage, a conventional fire substantially similar to or less intense than the fires encountered on September 11, 2001, likely would not have led to the collapse of a WTC tower.&#8221; (NIST NCSTAR 1, p. 176) Jones may be right when he says that heat transport away from the fire zone may not have been considered, but the fact is that the conductivity of steel is not that good (as he points out himself elsewhere in his paper), and localised heating is very easy. One only has to look at a workman cutting through steel with an oxyacetylene torch to realise that heat transport away from the cutting area is poor.



Jones &#8220;The computerized models of the Towers in the NIST study, which incorporate many features of the buildings and the fires on 9-11-01, are less than convincing. &#8230; The NIST report makes for interesting reading. The less severe cases based on empirical data were discarded because they did not result in building collapse. But &#8216;one must save the hypothesis,&#8217; so more severe cases were tried and the simulations tweaked, as we read in the NIST report: &#8230;&#8221;



Jones has an important point here, that computerised models, along with all the diagrams, sketches and visualisations presented in the official reports (and elsewhere), are open to challenge. But the term &#8216;tweaking&#8217; is a rather leading one (though not as leading as the term &#8216;revisionist&#8217; that Griffin uses). The point of adjusting the model&#8217;s parameters until the model shows collapse is to arrive at parameters consistent with the hypothesis. The parameters themselves are then open to scrutiny. As NIST says, quoted by Jones: &#8220;To the extent that the simulations deviated from the photographic evidence or eyewitness reports [e.g., complete collapse occurred], the investigators adjusted the input, but only within the range of physical reality. Thus, for instance,&#8230;the pulling forces on the perimeter columns by the sagging floors were adjusted... &#8221; NIST is saying that the parameters are &#8220;within the range of physical reality,&#8221; so it is up to Jones to demonstrate that they are not, in which case the NIST hypothesis would look weak. But instead Jones mocks the modelling process itself by saying &#8220;How fun (perhaps) to tweak the model like that, until the building collapses -- until one gets the desired result.&#8221; This misrepresents the purpose of the modelling, which in reality is to arrive at parameters then open to scrutiny. But Jones merely puts forward some opinion regarding other fire models which failed to predict collapse, without any mention of whether those models included the two additional factors that are core to the NIST hypothesis: structural damage, and insulation damage.



Jones: &#8220;So how does the NIST team justify the WTC collapses, when actual models fail to collapse and there are zero examples of fire-caused high-rise collapses? Easy, NIST concocted computer-generated hypotheticals for very &#8220;severe&#8221; cases, called cases B and D (NIST, 2005, pp. 124-138). Of course, the details are rather hidden to us. And they omit consideration of the complete, rapid and symmetrical nature of the collapses.&#8221;



Jones persists here in ignoring what NIST are saying: that their models do predict collapse for a certain range of parameters (within the range of physical reality), and that the collapse was not due to fire alone, but due to fire + structural damage + insulation damage. It is true that NIST chose not to consider the dynamics of the structures once collapse was initiated, but they had no particular reason to do so.



Jones concludes this section by saying:



&#8220;What about the subsequent complete, rapid and symmetrical collapse of the buildings? What about the observed squibs? What about the antenna dropping first in the North Tower? What about the molten metal observed in the basement areas in large pools in both Towers and WTC 7 as well? Never mind all that: NIST did not discuss at all any data after the buildings were &#8220;poised for collapse.&#8221; Well, some of us want to look at ALL the data, without "black-box" computer simulations that are &#8220;adjusted,&#8221; perhaps to make them fit the desired outcome. An hypothesis which is non-refutable is non-scientific. On the other hand, Occam's razor suggests that the simplest explanation which addresses and satisfies ALL the evidence is most probably correct.&#8221;



In this paper we meet all of Jones&#8217;s objections made here. If Jones wants to really put forward a hypothesis that satisfies all the evidence, then that hypothesis (controlled demolition) needs to be spelled out in some detail to see if it can withstand the kind of scrutiny that the impact / fire hypothesis has been exposed to.


2.13 NIST's Failure to Show Visualizations



Jones may have a valid criticism here, but equally he may not. To &#8216;show&#8217; visualisations is precisely what NIST have done in their report, by including numerous diagrams generated by the modelling software. Perhaps Jones would like access to the software itself plus the final database and its variants, in order to better understand the model. But I don&#8217;t know how common it is to make copies of proprietary software and datasets available on request. Certainly it is difficult, without substantial resources, to obtain such software, and to construct the datasets necessary for such visualisations. But the onus is on Jones, if he wants to show the validity of the CD theory, to attempt at least a basic model of the proposed demolition sequence, and to test it on available software.


2.14 Jones&#8217;s Summary



Jones concludes his case with this summary:



Jones: &#8220;Remarkably, the controlled demolition hypothesis accounts for all the available data rather easily. The core columns on lower floors are cut using explosives/incendiaries, near-simultaneously, along with cutting charges detonated up higher so that gravity acting on now-unsupported floors helps bring down the buildings quickly. The collapses are thus near-symmetrical, rapid and complete, with accompanying squibs -- really very standard stuff for demolition experts. Thermate (whose end product is molten iron) used on some of the steel columns readily accounts for the molten metal which then pooled beneath the rubble piles as well as the sulfidation observed in steel from both the WTC 7 and Towers rubble piles (points 1 and 2 above).



I believe this is a straightforward hypothesis, much more probable actually than the official hypothesis. It deserves scientific scrutiny, beyond that which I have been able to outline in this treatise.&#8221;



I have shown that the controlled demolition hypothesis does not account for the available data at all, and that this summary by Jones is absurd. If the core columns on lower floors had been cut, then the building would have been observed to have collapsed starting from that point, pancaking into the lower floors. It did not. If the speed of descent required cutting charges detonated higher up, then other buildings falling at the same speed would do so because of such charges. They do not. If the observed &#8216;squibs&#8217; were due to controlled demolition, they would have just appeared prior to collapse, and would not involved prolonged expulsion of material. They did not. Thermate is just not &#8216;standard stuff&#8217; for demolition experts: they never use it because its timings are uncontrollable, and its combustion products cannot cut steel columns. It is simply bad science for Jones to say: &#8216;The core columns on lower floors are cut using explosives/incendiaries, near-simultaneously&#8217; (my italics) because the slow action of an incendiary like thermite makes any attempt at precise timings impossible.



Molten metal beneath the rubble may have a number of causes, the most likely of which is the mgh energy of the building. If only 0.1 % of its collapse energy (one thousandth) were converted to heat, then that would be sufficient to melt a metric tonne of steel.



In another of Jones&#8217;s concluding remarks he says: &#8220;The controlled-demolition hypothesis cannot be dismissed as "junk science" because it better satisfies tests of repeatability and parsimony. It ought to be seriously (scientifically) investigated and debated.&#8221; [my italics]



It is precisely because the events of 9/11 are not repeatable that makes the science around its investigation difficult. In real scientific terms the different hypotheses would have to be tested by flying similar aircraft into similar buildings: clearly impossible. But Jones&#8217;s appeal to &#8216;parsimony&#8217; is instructive: it seems that he would like a simple explanation of the events instead of the complex impact-plus-fire-plus-insulation-damage &#8216;official&#8217; hypothesis. We show here that controlled demolition is far from the parsimonious account that he believes, because when examined seriously it generates far more problems than it solves.

I will conclude this section with a brief summary of the argument put forward by Brent Blanchard against explosive demolition. As Blanchard is an expert on this topic, it is up Jones to defeat his simple but powerful points: (1) that the impact and subsequent fires would have set off or destroyed any pre-planted explosives, (2) that it would have been impossible for a team to plant the explosives between impact and collapse in the case where such explosives were not pre-planted, and (3) that seismic recordings show none of the tell-tale signatures of explosives leading up to the collapse of any of the buildings. I'll return to point 3 in section 3.3.


3 Additional Arguments for the CD Hypothesis



Jones in his online paper does not rehearse all the arguments put forward by CD theorists, so for completeness I list and address them here.



1. Timing of Tower collapses in reverse order of impact

2. Energy required to pulverise concrete and produce dust clouds greater than potential energy of buildings

3. Seismic recordings made by Columbia University consistent with controlled detonations

4. Sudden onset of collapse consistent with demolition

5. Core columns should have remained standing

6. Explosions in the sub-basement



There are of course many more, but some cut-off is required, as even the CD theorists point out. They call the more outlandish suggestions, e.g. that the Towers were brought down by missiles, a &#8216;poisoning of the well,&#8217; perhaps suggesting even that there is a conspiracy to discredit the CD theory with totally implausible ideas. We are attempting to show however that even any sober variant of the CD theory faces difficulties far greater than the IF theory.


3.1 Timing of Tower collapses



Griffin cites a theory by Meyer that suggests that the fire in the South Tower had less fuel than in the North Tower and therefore went out earlier, despite having been initiated later. Those controlling the demolition (in this imagined scenario) were then forced to detonate their cutter-explosives at that point to bring the building down, and then waited until the fire in the North Tower went out until they brought that down. (NPH, p.18) But Griffin fails to put forward the NIST hypothesis, stated in Finding 58 (NIST NCSTAR 1-6, p.338):



&#8220;The time it took for each WTC tower to collapse was due primarily to the difference in structural damage, the time it took the fires to travel from the impact area across the floors and core to critical locations, and the time it took to weaken the core and exterior columns. WTC 2 had asymmetric structural damage to the core, including the severing of a corner core column, and WTC 1 had more symmetrical damage. The fires in WTC 2 reached the east side of the building more quickly, within 10 min to 20 min, than the 50 to 60 min it took the fires in WTC 1 to reach the south side.&#8221;



It is worth clarifying this a little: the difference in structural damage, and hence the subsequent sequence of events, was due to two factors: the much faster speed of the plane that hit WTC 2 compared to the plane that hit WTC 1, and the orientation of the plane to WTC 2, which meant that it (a) created a more asymmetrical impact zone, as confirmed in the tilting of the entire structure above, and (b) had a much shorter distance to travel in order to impact on the core structure of the building.



We note also that Mark Loizeaux had instinctively predicted that WTC 2 would collapse earlier, because it was hit lower down. His implication, clearly, is that the extra weight on the impact zone would cause structural supports to give way more quickly.


3.2 Energy Required to Pulverise Concrete



The CD theorists are drawing on two factors in arguing that the pulverisation of the concrete in the Towers could not have been the product of gravitational collapse. The first argument is intuitive: it just seems improbable, judging from the photos and videos of the early stage of collapse, especially before the collapse has reached any speed. The second factor is a calculation made by Jim Hoffman, and widely cited.



Before looking more closely at the calculations, I can point out again that it is a knowledge of demolition that provides the evidence here against the CD theory. Quite simply, in controlled demolition, the proportion of pulverisation accounted for by the explosives is negligible. To state again the first principle of explosive demolition: explosives initiate the collapse, gravity does the rest.



In Hoffman&#8217;s calculations on the energy required to produce the dust cloud he starts with an estimate of the dust cloud volumes from this photograph:





He proceeds to make estimates of the volume of this cloud, and the expansion of it as an entity, starting from the volume of the towers. Along the way, he has to make numerous other estimates, including the average particle size of the cloud and so on. He claims at each stage to make a conservative estimate, and concludes his calculations thus:



&#8216;The amount of energy required to expand the North Tower's dust cloud was many times the entire potential energy of the tower's elevated mass due to gravity. The over 10-fold disparity between the most conservative estimate and the gravitational energy is not easily dismissed as reflecting uncertainties in quantitative assessments.&#8217;



This assessment that the dust cloud alone required ten times the North Tower&#8217;s gravitational energy (mgh energy) to produce is widely cited by the CD theorists, including Griffin, and is of course startling. But they do not point out that the mgh energy of the North Tower is alone equivalent to about 270 tonnes of high-explosive TNT, and for both towers together 540 tonnes. If Hoffman&#8217;s calculations are to be taken seriously, this requires a total of 5,400 tonnes of TNT or equivalent explosives, less the 540 mgh equivalent. Hoffman&#8217;s calculations would therefore require nearly 5,000 tonnes of high explosive to be packed into the two towers (5 kilotonnes of TNT equivalent). By way of comparison, the nuclear bomb dropped on Hiroshima is estimated at between 12 and 14 kilotonnes of TNT equivalent. Can Hoffman be serious?



As of August 2006, even Hoffman doesn&#8217;t seem to be serious, as he has now reached version four of his analysis, which is supposed to replace his previous versions, but which he chooses not to place on the internet (version four is at: The North Tower's Dust Cloud and has withdrawn all his estimates and calculations). There is no indication that his research has been submitted for publication and hence peer review by scientists competent to assess his estimates and calculations. All we can do at this stage is point out that his claim of the ten-fold disparity in energy requirements, as a conservative disparity, would require the conspirators to hide of the order of five thousand tonnes of TNT equivalent in the Twin Towers, an equivalent of more than a third of the Hiroshima bomb. It is more likely however that his train of assumptions is faulty, perhaps even his starting point in attempting to model the immense complexity of the dust cloud as the expansion of a discrete volume of gas.



As to the energy required to pulverise the rubble, the calculations are uniquely dependent on two estimates: the average size of the particles, and the strength of the material. The CD theorists rely on only the most general of guesses as to the first figure, and insist on using only the strength of concrete in their calculations. Given that a significant proportion of the dust would have been generated from plaster, with a much lower strength, their estimates must be regarded as unreliable. Technically, the production of rubble or powder from rock or aggregate is known as comminution, and the energy required depends on what is known as the Bond work index: this is highest for rock, less for concrete, and much smaller for plaster.


3.3 Seismic Recordings



Many CD theorists draw attention to seismic recordings as evidence of the CD theory. Griffin (for example), drawing on Hufschmid, cites seismic data from Columbia University to support the CD theory:



&#8216;In each case, &#8220;the shocks increased during the first 5 seconds then dropped abruptly to a lower level for about 3 seconds, and then slowly tapered off.&#8221; This pattern, Hufschmid suggests, reflects the fact that the first explosives detonated were those near the tops of the towers, where the steel columns were the thinnest. The shocks get stronger as the detonation pattern, controlled by a computer programme worked its way down.&#8217; (Griffin TNPH, p.19)



This is easily shown to be fallacious. Firstly, as the one of Columbia authors confirmed in a later email, their seismic data &#8220;are far too weak in signal-to-noise ratio and far too speculative in terms of signal source to be used as a means of contradicting the impact times &#8230;&#8221; (Commission, p.462) But the key mistake however, is the idea that any building is demolished by a progressive wave of explosions either working its way up or down a building.



Popular Mechanics gives a good account of why the seismic spikes do not support the CD theory: Debunking the 9/11 Myths: Special Report - Popular Mechanics.

Brent Blanchard devotes section 4 of his paper to the issue of seismic recordings on 9/11. Blanchard is Senior Editor of ImplosionWorld, a website which posts details of explosive demolitions, and also Director of Field Operations at Protec Documentation Services, Inc. Protec works in the field of vibration monitoring and structure inspection, a key service to both the construction and demolition industries. Vibration monitoring performed by independent experts has long been considered crucial for companies carrying out explosive demolition, because owners of nearby buildings are keen to sue if any cracks or other structural damage appears. The field seismographs used by Protec and others provide the key scientific evidence for disturbances that may have caused damage, and there were a number of such seismographs operated by Protec on 9/11 in the vicinity of Ground Zero, for monitoring construction sites. Blanchard tells us that data from these machines, and seismographs operated elsewhere, all confirm single vibration events recording the collapse. None of them record the tell-tale 'spikes' that would indicate explosive detonations prior to collapse. In his words:


This evidence makes a compelling argument against explosive demolition. The laws of physics dictate that any detonation powerful enough to defeat steel columns would have transferred excess energy through those same columns into the ground, and would certainly have been detected by at least one of the monitors that were sensitive enough to record the structural collapses. However, a detailed analysis of all available data reveals no presence of any unusual or abnormal vibration events.


3.4 Sudden Onset of Collapse &#8216;Consistent with Demolition&#8217;



This is one of the central myths of the CD theory. NIST show clear photographic evidence of the bowing of the exterior walls and collapse of interior floors in both Towers, with timings showing an acceleration of this bowing prior to the initiation of collapse. There was no sudden onset of collapse consistent with demolition. On the contrary the CD theory is unable to explain the bowing and other structural deformations prior to collapse. Eyewitness accounts from firemen also confirm a huge bulge in the south elevation of WTC 7 prior to collapse, the phenomenon more than any other that persuaded fire chiefs to withdraw their forces from danger.


3.5 Core Columns &#8216;Should Have Remained Standing&#8217;



Many CD theorists make the assertion that the &#8216;core columns should have remained standing&#8217; during the collapse of the Towers, presenting the metaphor of records (as floors) sliding down the central spindle (as the building core). But they do not consider the NIST explanation which points out that the core columns were designed only to withstand compressive loads, whereas the outer columns were the ones designed to withstand all lateral loadings (principally winds up to hurricane speed). As each floor collapsed it would have created lateral forces on the core columns which were sufficient to either tear away the bolts or sever the columns themselves as they &#8216;peeled&#8217; away from the centre. If the CD theorists insist that explosives were used to sever the core columns, then this commits them to a variant of the CD theory requiring explosives on every single floor, multiplying the tonnage of explosive required by a factor of around 100. It also commits them to a sequential detonation, which would travel down in the Towers and up in WTC 7, requiring technologies well beyond anything seen in industrial practice.


3.6 Explosions in the Sub-Basement



In an afterword in Jones&#8217;s paper he reports an eye-witness statement from William Rodriguez:



&#8220;My basis was, like I told the Commission, there was an explosion that came from under our feet, we were pushed upwards lightly by the effect, I was on basement level 1 and it sounded that it came from B2 and B3 level. Rapidly after that we heard the impact far away at the top.&#8221;



Jones takes this as evidence for the CD theory, firstly that explosions were heard or experienced at the ground or basement level, and secondly that subsequent sounds were heard, assumed to be the impact of the planes. The IF theory as elaborated by NIST accounts only for the &#8216;explosions&#8217; at ground and basement levels: these were due to the fuel-air mix forced down shafts that had been opened up at the impact levels by the destructive impact of the planes. NIST report that not only a fuel-air mix was propelled down the shafts in the core of the building, but the force of these was sufficient to smash lift cages to the ground. People were killed and injured in these events, and windows were blown at the concourse level.


4 David Ray Griffin and the Dustin Mugford DVD



A DVD produced and directed by Dustin Mugford is distributed by 911revisited.com and is called &#8216;September 11 Revisited: Were Explosives Used to Bring down the Buildings?&#8217; I regard the DVD as a good example of the kind of one-sided propaganda that pressure groups use to convey their beliefs. It is propaganda because it deploys the classical rhetorical techniques of loaded terminology and repetition of its message, and it is one-sided because it pretends, as do all the counter-orthodoxies, that there is only the official version and the counter-orthodoxy. They do not mention the groups I have referred to above, which, independently of any official or Federal account, set out to disprove the counter-orthodoxies, offering evidence that would make the arguments balanced.



The film opens with the repeated use of the word &#8216;explosive&#8217; in such a way as to reinforce, in advance, the thesis put forward, that explosives brought down the WTC buildings. A range of eye-witnesses use the term in their accounts, but we have argued above (section 2.7) that no eye-witness has been played audio tapes of the signature &#8216;crack&#8217; of demolition explosives and asked to estimate their similarity or otherwise to the reports they recall hearing on the day. Characteristic of the appeal of the entire counter-orthodoxy is the single phrase uttered by a reporter in one of the clips looking on as the destruction unfolded: &#8216;This defies belief&#8217; (13:54 into the video). This is a natural response for the lay person, but the trained scientist should not then reach for the apparently easy explanation for it all: explosives.



At 18:53 into the video a reporter reminds us that Jones is putting his ideas forward as a hypothesis only, not as fact, and is calling for a fresh investigation to establish the truth. But David Ray Griffin, speaking next on the video, says: &#8216;The collapses of the Twin Towers and building number 7 had to have been examples of controlled demolition, brought about by thousands of explosives, placed throughout each of the buildings.&#8217; Griffin, not a trained scientist, but a philosopher and theologian, has made the unforgivable error in science: to jump from a statement of hypothesis to a statement of fact. He is speaking from a podium marked &#8216;University of Wisconsin, Madison&#8217; and delivers these lines with gravity and simplicity. A lay audience is inevitably impressed by his status as an academic, and the setting of the talk. They were given no chance to contemplate the possibility that the &#8216;thousands of explosives&#8217; were merely a theory, based, as I have shown, on a complete misunderstanding of the science and practice of industrial explosive demolition. But Griffin, not prepared to wait for the further scientific investigation that Jones is calling for, has already made his mind up. He continues: &#8216;No foreign terrorist could have obtained the kind of access to the buildings this would have required.&#8217;



Griffin, untrained in science, and seemingly completely unaware of the actual nature of explosive demolition states the CD mantra: &#8216;The buildings collapsed straight down and at virtually freefall speed, as in controlled demolitions.&#8217; We have seen that WTC2 certainly did not collapse &#8216;straight down&#8217;, and that the &#8216;virtually&#8217; freefall speeds in controlled demolitions, are nothing to do with explosives, but are purely gravity powered.



Untrained in science, but well-versed in public speaking, Griffin smiles at the audience and says: &#8216;Try this: take a piece of concrete, and drop it a little over a thousand feet, and see if it pulverises into very fine dust. It won&#8217;t happen.&#8217; But we have shown that the pulverisation of concrete in conventional explosive demolition has, again, nothing to do with explosives. It is gravity that reduces the buildings in controlled demolition to rubble and dust: the thousands of tons above the piece of concrete, acting something like a hydraulic press, are what smashes it. The mgh energy in each of the Towers, to repeat the point, was equivalent to 270 tons of TNT: no additional explosives were needed. Griffin also suggests that the very high temperatures in the basement rubble of the Towers &#8216;points to the existence of very powerful, precisely placed explosives.&#8217; But explosives are incapable of heating up any significant quantity of metal, because their energies are dissipated in fractions of a second as shock waves. Their use in controlled demolition is to cut, not to pulverise or to heat or melt.



Griffin goes on to ridicule the official &#8216;pancake&#8217; theory. He says, with a grin inviting the audience to share in the joke: &#8216;Now, even if this theory were remotely plausible, can you imagine it pancaking at freefall speed?&#8217; Note that Griffin has moved on from &#8216;virtually&#8217; freefall speed to straight freefall speed: bad science. As I have shown however, whatever the difficulty in imagining pancaking taking place at these high speeds, it is the practice of controlled demolition that proves Griffin completely wrong again. The speed of pancaking in conventional explosive demolition has nothing to do with the use of explosives: it purely gravity powered.



The Griffin section of the video concludes with the issue of the core columns and the idea that they should have remained standing even if the floors did pancake according to the official theory. He uses the analogy of records stacked up above a turntable moving down, but leaving the spindle intact. But, instead of considering the physics of a vertical column, designed for compressive not lateral loading, pulled away from the vertical by the collapsing floor members, and asking whether the estimated shear loads were sufficient to fracture them or to break the joints, Griffin resorts to another popular 9/11 myth: that the 9/11 Commission Report deny the very existence of the core columns. He says: &#8216;It avoided the problem, incredibly, by simply denying the existence of these columns. &#8230; This supposedly authoritative report said that the interior core of the buildings was a hollow steel shaft in which elevators and stairwells were grouped. Such a desperate lie is a sure sign of a cover-up.&#8217;



It would indeed be a &#8216;desperate lie&#8217; if the final report actually denied the existence of the core columns. It is true, in fact, that the Commission Report includes this statement: &#8216;&#8230;These exterior walls bore most of the weight of the building. The interior core of the buildings was a hollow steel shaft, in which elevators and stairwells were grouped.&#8217; But this statement is tucked away at the end of the document (on page 541 of 567) as part of a footnote to page 278. The purpose of the footnote was generally to direct the reader to the FEMA report which contained more details on the building. But the Commission Report never set out to give an account of the collapse of the buildings, as that task was completed in broad terms in the FEMA report, and in much more detail in the NIST report, both of which deal extensively with the core columns. The NIST report has this to say on the question of loading between the exterior columns and the core columns:



The dense array of columns along the building perimeter was to resist the lateral load due to hurricane-force winds, while also sharing the gravity loads about equally with the core columns. [NCSTAR 1, p.6]



So, how much of a desperate lie are the offending few lines tucked away in a footnote at the end of the Commission Report? It is clearly not accurate, as the gravity loads are shared equally across the two types of column (though the exterior columns bore all of the lateral weightings). But to the lay audience at Madison University Griffin&#8217;s account would suggest that the official reports as a whole had conspired to deny the importance of the core columns, or even their existence. Anyone who has read the FEMA and NIST reports with their focus on technical issues, and who can see from the Commission Report that it did not set out in any of its chapters to give an account of the mechanics of collapse, must conclude that it is Griffin who is perpetuating a lie.



What then of Griffin&#8217;s two books on the subject: The New Pearl Harbour (TNPH), and The 9/11 Commission Report (TNCR)? In both books Griffin repeats what I believe to be the bad science put forward by Jones and others, with no attempt to balance their claims with those by other technical experts, official or otherwise. And, as the TNCR title suggests, he repeats in it his absurd claim that the official reports omit the core columns (p.27). Here is an extract:



With regard to the more basic question &#8211; Why did the Twin Towers collapse at all? &#8211; the Commission implies an answer by saying that



the outside of each tower was covered by a frame of 14-inch-wide steel columns. &#8230; These exterior walls bore most of the weight of the building. The interior core of the buildings was a hollow steel shaft, in which elevators and stairwells were grouped. (541n1)



This implicit explanation, however, involves a complete falsification, because the core of each tower was composed not of a &#8220;hollow steel shaft&#8221; but of 47 massive steel columns, &#8230;



Griffin concludes the section by saying &#8216;The Commission avoids this embarrassing problem by simply denying the existence of those massive steel columns &#8211; therefore either demonstrating enormous ignorance or telling an enormous lie.&#8217; Enormous lie? A paragraph buried in the footnotes at the end of the document which, true, is inaccurate, but by no stretch of the imagination can be an answer to the question: Why did the Twin Towers collapse at all? Why on earth should anyone believe that this document chooses to answer a very complex technical question by a remark buried in the footnotes, the purpose of which footnote is to refer the reader to the FEMA report? Why should anyone believe that the Commission are guilty of &#8216;either enormous ignorance or telling an enormous lie&#8217; in connection with the Twin Towers collapse when the technicalities of this event are thoroughly dealt with in the FEMA and NIST reports, both of which deal extensively with the core columns?



I regret to say that I have found both of Griffin&#8217;s books to be on a par with the Dustin Mugford DVD: that is they are one-sided propaganda. It would take a book-length refutation to fully answer Griffin, but I believe that the discussion here shows him to be an unreliable thinker on such complex issues. I think it instructive however to ask the question why his methods of argument seem so persuasive to many. His approach seems to be to multiply accusations, without giving each point a careful and balanced discussion. A friend of mine suggests that this approach in argument is like a rope made from many threads: each thread on its own may be weak, but the rope as a whole is strong. Appealing as this image is, I cannot shake off the suspicion that, in argument, as opposed to making ropes, this method is alarmingly like mud-slinging.



I will give an example: Griffin states early on in TNCR that &#8216;One problem is that at least six of the nineteen men officially identified as the suicide hijackers reportedly showed up alive after 9/11&#8217; (p.19) This is naturally intriguing, so I Googled the first name he cites: Waleed M. al-Shehri, and the first site I encountered was the Wikipedia entry for the hijacker. Wikipedia has this to say:



Waleed and Wail were both mistakenly reported to have been found alive and well, by the BBC later in 2001. They were initially reported in error by a Saudi newspaper editor as the sons of Ahmed Alshehri, a senior Saudi diplomat stationed in Bombay, India. On September 16, 2001, the diplomat Ahmed Alshehri denied that he was the father of the two hijackers. Wail claims he did attend Embry-Riddle Aeronautical University in Daytona Beach, Florida - but was the victim of mistaken identity, since he used that training to secure his current position with a Moroccan airline company. Saudi Arabia has confirmed his story, and suggested he was the victim of identity theft.



Why doesn&#8217;t Griffin mention the opinion of Wikipedia and the Saudi government, and allow the reader to decide? The muddle over the transliteration of Arabic names is endemic in the relationship between the US and the Islamic world, and is part of the wider cultural gap that allows for such misunderstandings to proliferate. Griffin goes on to say:



How can we believe that the Commission&#8217;s report was based on &#8220;exacting investigative work,&#8221; as we are told by Kean and Hamilton in the Preface, if the staff did not even learn, from sources such as the Associated Press, the Telegraph, and the BBC, that six of the men originally identified as hijackers were still alive?&#8217; [TNCR p. 20].



But I would reply to Griffin: how can we believe your books when you don&#8217;t check up on anything, whether it is the science of demolition, or erroneous reports by the BBC?



It seems to me that Griffin is content to pick up on any accusation germane to his thesis, and bind it into his &#8216;rope&#8217; without giving the reader any suggestion that evidence exists to the contrary. By moving breathlessly from one such accusation to another, he draws the reader along to his grand conclusion: to me it seems more like mud-slinging than a coherent argument. He also seems to revel in calling any official who changes their mind on any of the events of 9/11 &#8216;revisionists.&#8217; This is an extraordinary word to use, deriving I believe from the Communist era, and intended to discredit through the emotional charge that the word carries. But good science is always open to revision, and the fact that an investigator changes their mind as new evidence emerges is a positive sign, not immediate proof of conspiracy.


5 Conclusions



Good science involves the slow development of theories based on careful checking and re-checking of data. Hence I am surprised that Professor Jones, trained in science, should be so hasty in his presentation, including the apparent unwillingness to properly investigate the science and practice of explosive demolition, and the even graver errors such as assertions that a large section of the Twin Towers was reduced to dust in mid-air, when video footage clearly shows the section he refers to falling as a whole (and fully conserving angular momentum.) I am not surprised however that David Ray Griffin, as a theologian and philosopher, should be utterly cavalier about scientific evidence in particular and other evidence in general. My studies of the Enlightenment philosophers showed that they collectively may have been inspired by the emerging discipline of physics, but completely failed to grasp its workings and real significance, and resented its emerging cultural prominence. From Hume onwards, philosophers have sought to reclaim what they had regarded as their birthright: the cultural status of philosophy as the &#8216;queen of sciences.&#8217; Rorty represents the ultimate postmodern rejection of good science: Griffin merely ordinarily ignorant of it.



I leave the author of the Debunking 911 site the last word, sentiments I wholeheartedly agree with:



This is the kind of thing the "scholars" want us to pay millions more investigating. Personally, I could think of a few other pressing issues to spend millions on. Like research into the collapse of critical thinking skills in American and UK universities.
 
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Why don't you start by answering Dabong's question about how many hijackers are still alive.

Can you answer it? I lost track of this story a while ago. There were suggestions of some of them turning up alive elsewhere though.

I think physics and mathematics can prove anything Keysor. There's a lot of unknowns in what happened on 911. Some inconsistencies do exist, but even if one could prove or disprove 911, it would not affect the war on terror's path one bit..perhaps it shouldn't anyway..Bin Laden has sworn to destroy America (the real one, not the fat one with a cloth on his head in some of the videos). So, one can't really blame them for going after him..unless one wants to open up a new can of worms suggesting Bin Laden still works for the CIA..but then one will never know such things. So it's all fruitless.
 
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Can you answer it? I lost track of this story a while ago. There were suggestions of some of them turning up alive elsewhere though.

I think physics and mathematics can prove anything Keysor. There's a lot of unknowns in what happened on 911. Some inconsistencies do exist, but even if one could prove or disprove 911, it would not affect the war on terror's path one bit..perhaps it shouldn't anyway..Bin Laden has sworn to destroy America (the real one, not the fat one with a cloth on his head in some of the videos). So, one can't really blame them for going after him..unless one wants to open up a new can of worms suggesting Bin Laden still works for the CIA..but then one will never know such things. So it's all fruitless.

I am sure there are inconsistencies even in the most Open/shut cases. And as was mentioned in the Alexander Cockburn article there is a whole industry which looks into finding these inconsistencies and making them look bigger than they are. Meanwhile whilst a bunch of cretins are looking into false crap the REAL conspiracies are pushed into the background. The Governments are getting away with more serious crap whilst heroes who spout crap about 9-11 are deflecting everyones attention.

I loathe these stupidities. Unfortunately it is easy to push this nonsense onto certain elements who "want to believe "

On and Physics and mathematics I would say this. It has purity which cannot be twisted. 2+2 will always be 4
 
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This one is from BBC. Please tell me what you think of this. Also...please note that FBI Director Mullen even admits the identity of the hijackers was thrown into doubt way back in 2001.

BBC NEWS | World | Middle East | Hijack 'suspects' alive and well

Hijack 'suspects' alive and well
Waleed Al Shehri
A man called Waleed Al Shehri says he left the US a year ago

Another of the men named by the FBI as a hijacker in the suicide attacks on Washington and New York has turned up alive and well.

The identities of four of the 19 suspects accused of having carried out the attacks are now in doubt.

Saudi Arabian pilot Waleed Al Shehri was one of five men that the FBI said had deliberately crashed American Airlines flight 11 into the World Trade Centre on 11 September.

His photograph was released, and has since appeared in newspapers and on television around the world.

Hijacking suspects
Flight 175: Marwan Al-Shehhi, Fayez Ahmed, Mohald Alshehri, Hamza Alghamdi and Ahmed Alghamdi
Flight 11: Waleed M Alshehri, Wail Alshehri, Mohamed Atta, Abdulaziz Alomari and Satam Al Suqami
Flight 77: Khalid Al-Midhar, Majed Moqed, Nawaq Alhamzi, Salem Alhamzi and Hani Hanjour
Flight 93: Ahmed Alhaznawi, Ahmed Alnami, Ziad Jarrahi and Saeed Alghamdi
Now he is protesting his innocence from Casablanca, Morocco.

He told journalists there that he had nothing to do with the attacks on New York and Washington, and had been in Morocco when they happened. He has contacted both the Saudi and American authorities, according to Saudi press reports.

He acknowledges that he attended flight training school at Daytona Beach in the United States, and is indeed the same Waleed Al Shehri to whom the FBI has been referring.

But, he says, he left the United States in September last year, became a pilot with Saudi Arabian airlines and is currently on a further training course in Morocco.

Mistaken identity

Abdulaziz Al Omari, another of the Flight 11 hijack suspects, has also been quoted in Arab news reports.

Abdelaziz Al Omari
Abdelaziz Al Omari 'lost his passport in Denver'
He says he is an engineer with Saudi Telecoms, and that he lost his passport while studying in Denver.

Another man with exactly the same name surfaced on the pages of the English-language Arab News.

The second Abdulaziz Al Omari is a pilot for Saudi Arabian Airlines, the report says.

Meanwhile, Asharq Al Awsat newspaper, a London-based Arabic daily, says it has interviewed Saeed Alghamdi.

Khalid Al-Midhar
Khalid Al-Midhar may also be alive

He was listed by the FBI as a hijacker in the United flight that crashed in Pennsylvania.

And there are suggestions that another suspect, Khalid Al Midhar, may also be alive.

FBI Director Robert Mueller acknowledged on Thursday that the identity of several of the suicide hijackers is in doubt.
 
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And one from the telegraph....of course.....STOLEN IDENTITIES....why not?...it fits the official story....but did they recant the story of the 19 hijackers and tell the world that the story isn't exactly like that anymore? They still refer to them as the 19 Saudi hijackers. So if these guys are alive...who did it then? And how do they know that THOSE guys are Saudi? And why don't they tell us who they are if they know?

Revealed: the men with stolen identities - Telegraph
Revealed: the men with stolen identities


By David Harrison
Last Updated: 2:03AM BST 23 Sep 2001

THEIR names were flashed around the world as suicide hijackers who carried out the attacks on America. But yesterday four innocent men told how their identities had been stolen by Osama bin Laden's teams to cover their tracks.

The men - all from Saudi Arabia - spoke of their shock at being mistakenly named by the FBI as suicide terrorists. None of the four was in the United States on September 11 and all are alive in their home country.

The Telegraph obtained the first interviews with the men since they learnt that they were on the FBI's list of hijackers who died in the crashes in New York, Washington and Pennsylvania.

All four said that they were "outraged" to be identified as terrorists. One has never been to America and another is a Saudi Airlines pilot who was on a training course in Tunisia at the time of the attacks.

Saudi Airlines said it was considering legal action against the FBI for seriously damaging its reputation and that of its pilots. The FBI released the list of 19 suicide terrorists three days after the attacks.

The statement said that the 19 "have been identified as hijackers aboard the four airliners". Photographs and personal details were published around the world with an appeal for "information about these individuals, even though they are presumed dead".

The Saudi Airlines pilot, Saeed Al-Ghamdi, 25, and Abdulaziz Al-Omari, an engineer from Riyadh, are furious that the hijackers' "personal details" - including name, place, date of birth and occupation - matched their own.

Mr Al-Ghamdi was named as a terrorist on the United Airlines flight that crashed in Pennsylvania - a plane said by some experts to have been heading for the White House.

He first knew that he was on the FBI's list when he was told by a colleague. Speaking from Tunisia, he said: "I was completely shocked. For the past 10 months I have been based in Tunis with 22 other pilots learning to fly an Airbus 320. The FBI provided no evidence of my presumed involvement in the attacks.

"You cannot imagine what it is like to be described as a terrorist - and a dead man - when you are innocent and alive." The airline was angry too. Officials brought Mr Al-Ghamdi back to Saudi Arabia last week for a 10-day holiday to avoid arrest or interrogation.

An official said: "We are consulting lawyers about what action to take to protect the reputation of our pilots." Mr Al-Ghamdi faced further embarrassment when CNN, the American television network, flashed a photograph of him around the world, naming him as a hijack suspect.

The FBI had published his personal details but with a photograph of somebody else, presumably a hijacker who had "stolen" his identity. CNN, however, showed a picture of the real Mr Al-Ghamdi.

He said that CNN had probably got the picture from the Flight Safety flying school he attended in Florida. CNN has since broadcast a clarification saying that the photograph may not be that of the accused.

Mr Al-Omari, who was accused of hijacking the American Airlines plane that smashed into the the World Trade Centre's north tower, said that he was at his desk at the Saudi telecommunications authority in Riyadh when the attacks took place.

He said: "I couldn't believe it when the FBI put me on their list. They gave my name and my date of birth, but I am not a suicide bomber. I am here. I am alive. I have no idea how to fly a plane. I had nothing to do with this."

Mr Al-Omari said his passport was stolen when his apartment in Denver, Colorado, was burgled in 1995. He had been studying engineering at Denver University since 1993. He was given a new passport in Riyadh on December 31, 1995 and returned to America to resume his studies in January 1996. After graduating last year he returned to Riyadh to join the electricity authority and later moved to the telecommunications authority.

The other two men accused of being terrorists are Salem Al-Hamzi and Ahmed Al-Nami. Mr Al-Hamzi is 26 and had just returned to work at a petrochemical complex in the industrial eastern city of Yanbou after a holiday in Saudi Arabia when the hijackers struck. He was accused of hijacking the American Airlines Flight 77 that hit the Pentagon.


He said: "I have never been to the United States and have not been out of Saudi Arabia in the past two years." The FBI described him as 21 and said that his possible residences were Fort Lee or Wayne, both in New Jersey.


Mr Al-Nami, 33, from Riyadh, an administrative supervisor with Saudi Arabian Airlines, said that he was in Riyadh when the terrorists struck.

He said: "I'm still alive, as you can see. I was shocked to see my name mentioned by the American Justice Department. I had never even heard of Pennsylvania where the plane I was supposed to have hijacked."

He had never lost his passport and found it "very worrying" that his identity appeared to have been "stolen" and published by the FBI without any checks. The FBI had said his "possible residence" was Delray Beach in Florida.

Last night the FBI admitted that there was some doubt about the identities of some of the suspects. A spokesman said: "The identification process has been complicated by the fact that many Arabic family names are similar. It is also possible that the hijackers used false identities."


The spokesman declined to say whether the FBI would apologise but added: "If we have made mistakes then obviously that would be regrettable but this is a big and complicated investigation."

When the list was published Robert Mueller, the FBI director, said that it was "fairly confident" that the names were not aliases.
 
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Zyxius, If these articles are to be believed, then why have no media groups updated the information? They're all from 2001. If they are still walking around, why are these guys not international celebrities for having survived head on crashes into buildings?

The western media alone does not carry stories, so why haven't Arab media updated the information also? Are the Arabs all complicit in this conspiracy also?
 
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The alleged hijackers are still alive. They have been on TV, they have been in the news...I dont know what else you want. BBC and Telegraph are two mainstream western media sources and they have reported these truths. You seem to be suggesting that they should be on every day in order for it to be believable. Why keep raising the bar? Its the truth...what more do you want?!
 
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