CIA's Predecessor To The SR-71 Blackbird Tested Electron Guns To Hide From Radars

[F-22Raptor]

The Central Intelligence Agency initiated the Oxcart program, which led to Lockheed's A-12 spy plane, the predecessor of the U.S. Air Force's SR-71 Blackbird, specifically because of concerns that the iconic U-2 Dragon Lady was becoming too vulnerable to Soviet and other hostile air defenses. The aircraft's primary advantages were in its ability to fly extremely high and fast, but it was apparent from the beginning of its development that those capabilities might not be enough to defend against existing and emerging threats at the time.

As a result, the A-12 itself featured then-state-of-the-art stealthy shaping together with radar-evading structures that made heavy use of composites and that were coated in radar-absorbing materials. The CIA undertook further efforts to explore more novel means of reducing the radar cross-section of the planes, including the development of a cesium-laced fuel additive intended to shield its rear aspect from radar waves using a concept called "plasma stealth," which you can read about in greater detail in this past War Zone feature. This same principle also led to the development of powerful electron guns that the A-12 could carry inside its fuselage to create similarly radar-absorbing fields in other directions, according to various declassified documents now available online via the CIA Records Search Tool, or CREST.


The CIA's search for a U-2 successor began in 1956 and in two years the Agency had determined the proposals from Lockheed and Convair represented the most viable designs. Stealthy features became the deciding factor.

"On 28 August 1959, Mr. Bissell [Dr. Richard Bissell] told me to come east for the 19th time in this competition," Clarence "Kelly" Johnson, the famous Lockheed engineer who for years ran the company's Advanced Development Programs (ADP) division, or Skunk Works, explained in a previously classified 1968 official internal history of the A-12. "He told me that we had won the competition, subject to our proof of low radar cross-section between that period and 1 January 1960."

Bissell was the CIA’s Special Assistant for Planning and Coordination and was in charge of the Oxcart program. He had threatened to cancel the entire project if the competing companies couldn't make significant progress in reducing the radar cross-sections of their designs. Ed Lovick, another Skunk Works engineer, who Johnson credits with coming up with the cesium fuel additive idea, says that development saved the A-12 in his own book, Radar Man: A Personal History of Stealth.

The A-12's engine nacelles and ducts also had chines on the outer edges and chined leading edges of the wings with saw-tooth-shaped baffles underneath the surface to further reduce the aircraft's radar returns. Curved wing extensions on the leading edges and canted rear vertical stabilizers, as well as spiked cones covering the inlets for the two huge Pratt and Whitney J58 engines, also helped deflect incoming radar waves.

Lockheed made good use of radar-absorbing composite materials in all of these areas, except for the spikes over the engine inlets. Literally on top of all of that was a layer of "iron paint," also referred to as "iron ball paint" because of the small iron balls mixed in, which also helped reduce the aircraft's radar signature. That paint's special blend, which Lockheed also used on the later SR-71, reportedly cost $400 per quart in the 1960s.

In spite of all of this, the CIA's fears about the potential vulnerability of manned reconnaissance aircraft persisted. The infamous Soviet shootdown of Gary Powers' U-2 on May 1, 1960, further fuel those concerns and ended spy plane flights over that country.

The introduction of new Soviet radars, particularly the P-14 Tall King, was also a major driving factor. The CIA, together with other U.S. Intelligence agencies and elements of the U.S. military, expended considerable effort in the 1950s and in the early 1960s, as the A-12 was still in development, gathering details about these radars through programs codenamed Melody and Palladium. Palladium involved a particularly complicated set of ruses to produce false radar returns and then observe the response from examples of these radars positioned in Cuba, allowing analysts to try to work out what radar operators were and weren't seeing on their screens, and thus how the A-12's own radar cross-section would fare against those sensors.

"In April 1963 we were directed to rebuild the aircraft chines to change the optimum radar cross-section at S-band to favor better performance against the 'Tall King,'" Johnson wrote in his 1968 history. "This was an expensive and (as it finally turned out to be) undesirable change."


Work on the cesium fuel additive, eventually known as A-50, offered one possible method of reducing the radar cross-section of the rear aspect of the aircraft. This was already a problematic area in the radar-evading work because of the jet's massive exhausts and the radar reflective plume from the J58s at full afterburner while flying at above Mach 3.

At its most basic, the general concept of plasma stealth involves using some means to create a cloud of ionized particles, or plasma, which is capable of absorbs electromagnetic radiation, such as radar waves, so they can't reflect back. Burning cesium in the super-heated exhaust stream would do just that at the back of the plane.


The obvious problem was that the exhaust stream only pointed rearward. A-50 could not produce a similar ionized cloud toward the front aspect of the aircraft, which would be most exposed as the aircraft approached the target area at the beginning of its reconnaissance pass. This is also when the aircraft would be most vulnerable.

One option the CIA considered, codenamed Emerald, was to install devices elsewhere in the aircraft that would create "a seeded plasma electric arc," similar to the effect of adding cesium in the exhaust stream, but in other directions. Another idea, codenamed Kempster, was to install electron guns that would emit electrically-charged particles to produce a similar effect.


Westinghouse Research Laboratories, a division of the Westinghouse Electric Corporation, and General Electric subsequently got contracts to develop these electron guns. Westinghouse eventually took the lead in the Kempster program.

The Kempster program sought devices that would be small enough to fit inside the chines on either side of the A-12 near the wing fairings, where they could help conceal the radar reflections from the engine inlet spikes. The goal was to have the electron guns project cones of radar-absorbing particles that would extend out approximately 300 inches, or 25 feet, from the chine, according to one 1964 report.


Electron gun technology was already well established at the time and it was, and still is, used in an array of different commercial products, including televisions and monitors that use cathode ray tubes, and manufacturing processes. A typical electron gun design uses a hot cathode at one end of a container to create a stream of electrons that then pass by electrodes and anodes that focus them into a beam and accelerates them, respectively.

The generation of the electron beam takes place in a vacuum region, which then creates the challenge of how to get it out into the ambient environment. One established method involves simply placing a medium, typically a sheet of some kind of metal foil, also known as a "window," at one end that the electrons can pass through.

Westinghouse used this method to create what it referred to as windowed and window tube designs. The problem with this method is that the metal strips energy from the beam as it passes through, potentially reducing its power, and cannot be too thick or it will block the beam entirely. Unfortunately, keeping the metal barrier sufficiently thin makes it fragile. This might not necessarily be a major problem in an industrial or similar setting, where workers might be more readily able to replace the window quickly. A system intended to work reliably on an aircraft flying more than three times the speed of sound is a completely different matter.

The focus ultimately shifted from these windowed designs to another method that allows the beam to leave the gun through an open orifice at one end and uses vacuum pumps to remove gases, such as ambient air, from the internal sections. This type of pumped system is notably heavier and bulkier than a windowed design. Beyond the electron gun itself, the complete system also needs a substantial power source and cooling systems to prevent dangerous overheating.

Getting a pumped device to work within the weight and space constraints of the chines, an area of the aircraft that would also experience serious physical strains and high temperatures when the aircraft was flying at Mach 3, presented challenges for Westinghouse. The company initially bought an industrial example straight from W. C. Heraeus in Hanau, West Germany and modified it for the Kempster program.

This system worked well enough, but was far too big to fit inside the A-12's chines. Flight testing of the Heraeus gun on one of the aircraft, known as Article 126, required its installation in the aircraft's main payload bay, or Q bay, with the beam pointing straight down. Had this configuration become operational, it would have limited the space inside the bay for cameras or other equipment.

"In conclusion, the undersigned believes that, even if [redacted] is successful in [the] operation of its KEMPSTER A, there is little chance that it will ever be used operationally, because of the great weight, 250 lbs or more, per gun and potentially high-power requirements," according to a 1963 CIA progress note on the program. The CIA also redacted the name of the author of that brief report. It is not entirely clear from the available CIA sources what systems were developed as part of the Kempster A phase and how they differ from those pursued as part of a second line of effort known as Kempster B.

Regardless, after working with designs based on the Heraeus gun, Westinghouse subsequently developed its own compact pumped "C-Gun" design, which did fit -inside the chines. A basic control panel was installed in the cockpit to allow the pilot to turn the system on or off, or to set it to a cool down mode, as well as select whether to project the beams from the right, the left, or both electron guns.

At least two flight tests took place in 1964, with an A-12 known as Article 131 carrying the electron guns, according to CIA reports. "The KEMPSTER equipment shutters opened but power failure occurred," according to a cable about a test flight on Dec. 11, 1964. The system worked as intended during another test flight six days later, according to another cable, but all further details are redacted.



Westinghouse built at least four prototype C-Guns, enough to equip two aircraft at any one time, but there is no indication that these were ever employed operationally. A now-declassified internal CIA history of the U-2 and A-12 programs says "this project proved unsuccessful," but offers no further details.

One issue may have been that the electron guns produced x-ray radiation as a byproduct of their operation, both in flight and during pre-flight checkouts on the ground. With regards to the Heraeus gun, there were concerns that this could impact the film in the cameras in the Q-bay.

This was, of course, a less pressing concern with regards to the chine-mounted C-guns, but there was still the matter of potentially dangerous x-ray exposure, especially to ground personnel during pre-flight checkouts. "Means were employed to assure safe conditions for all personnel concerned," according to a 1965 Westinghouse report.



As of October 1965, Westinghouse and General Electric were both still receiving funding from the CIA and National Reconnaissance Office for work on both Kempster A and Kempster B. The work on Kempster B was described at the time as a "theoretical study."


The CIA's U-2 and A-12 history, which the Agency first published in 1992, blames the U.S. Air Force's unwillingness to share electronic countermeasures technology with the Oxcart program as the reason for developing Kempster in the first place. The Air Force feared that A-12 operations would give the Soviets too much opportunity to analyze the countermeasures, according to the CIA.



The CIA did ultimately develop an electronic warfare package for the A-12 and that may well have sealed the fate of efforts to develop improved electron guns under Kempster B. It certainly appears to have offered sufficient protection, combined with the aircraft's speed and high altitude flight profile, that the Agency also does not appear to have ever employed the A-50 cesium fuel additive operationally, either.

The CIA did not even use A-50 during missions over North Vietnam in the 1960s where the threat of hostile fire was very real. On Oct. 30, 1967, CIA pilot Dennis Sullivan flew an A-12 on a mission over that country during which North Vietnamese air defenders fired at least six SA-2 Guidelinesurface to air missiles at his aircraft. Sullivan saw at least three of them detonate near him and contrails from the launches were also present in some of the pictures taken during the mission, according to an official CIA account of the sortie. The missiles came close enough to leave fragment lodged in the Oxcart's fuselage.

The CIA retired the A-12s in 1968. There's no evidence that the Air Force made any use of the work the CIA did under the Kempster program to help protect its SR-71s, which had begun flying missions in 1966, either. Those aircraft also utilized an advanced electronic warfare countermeasures suite, in addition to a stealthy shape and radar-absorbing features developed from those on the A-12, as their primary means of protecting themselves from enemy air defenses.


The basic concept of plasma stealth and using other particles to create radar wave-absorbing fields is said to have continued in both the United States in the Soviet Union for years after the Kempster program came to an end and the CIA retired the A-12s for good. As with the electron guns for the Oxcarts, information on most of these projects is limited. Most recently, the topic of plasma stealth did resurface in unconfirmed reports that the Russian 3M22 Zircon hypersonic cruise missile might use this principle, or something similar, to help conceal it from hostile radars.

Without knowing the exact reason why the CIA deemed Kempster to be a failure, it's hard to say whether or not electron guns could ever provide sufficiently useful radar-evading capabilities to outweigh their complexities compared to other stealth and electronic warfare technologies. Regardless, the project is definitely another interesting and little known piece of the A-12's history, which ties directly into the story of the SR-71, much of which is still unknown.


https://www.thedrive.com/the-war-zo...bird-tested-electron-guns-to-hide-from-radars


Makes you wonder about the classified technologies the US is working on today.

 

[Itachi]

Makes you wonder about the classified technologies the US is working on today.

Sure does

Is there a Chinese counter to this or have the been working on a similar program like the SR-72??

If not, then they have a lot of catch up to do.

 

[ابن_حیزون]

you seem to have forgotten Laser in your title

 

[Rafeh]

You do realize that this piece was written with a “perception engineering” intent for illiterate masses You could make an electron gun at home (using capacitors, voltage source, few wires). Olden day television sets, computer monitors were essentially electron guns with a screen. What classified about them. They were being manufactured even in not so developed countries.

The rest of the claims are just as meaningless. First I will give an analogy and then give a brief analysis related to this actual “secret technology described”.

Analogy: imagine you are in room and there is single open window. Some very loud noise (bandlimited) is coming into this room thorough that window. Can you place one or few speakers such that they will generate some counter soundwaves that will cancel this incoming noise completely. The answer is off course not. First incoming noise is distributed and reflected, diffracted etc. around the room changing its characteristics hence varies from point to point. To measure it exactly you need to distribute infinite number of point microphones and then have in general need nearly infinite “point speakers” also concurrently distributed in the room to cancel all this time and space varying noise completely. You can estimate and cancel this noise with finite number of “point microphones and speakers but only approximately. If this was possible even currently, there will be products in the market that will give a few speakers and you would have a room without a sound regardless of outside noise. The maker of such product would be a multi billionaire at least. Falsely claimed products exists but no real one, yet. In this example noise coming through window is analogous to incident radar wave and scattered noise from walls is akin to scattered field.

Same way, to cancel a scattered electromagnetic wave from a complex structure such as SR-71 you need to measure/estimate this scattered field first since due to complex multi-path scattering etc. it is impossible to predict it beforehand. Not to mention this scattered field has changed many of its characteristics relative to incident radar wave due to highly nonlinear and random interaction with the atmosphere, aircraft’s internal and external structures etc. That’s makes it even harder to estimate it that too in real time. May be in near future using appropriate surrogate models along with A.I. but certainly was not possible in the past.

I am assuming that you are planning to cancel all of it off course locally and nothing escapes to form the far field that can lead to aircraft detection. You would need to measure/estimate this extremely complex scattered field in Realtime too, then using a vast number of EM wave generators actively cancel this scattered field. This would be partially and hardly achieved in future sixth generation aircrafts. It was NOT possible even remotely in the past. Roughly it is akin to canceling acoustic sound waves in a given volume, such as a in a room

In the “article above” what they are saying is that since an electron beam radiates a time/frequency varying field, since modern television of that time, made in US, japan, china and everywhere else are already using this “unclassified technology” why not put some version of this widely available technology on SR-71 to see whether some of the scattered field gets cancelled or not. US had to do this experimentally since otherwise to do it theoretically they would need to solve very complex partial differential equations just to calculate interaction of scattered field with the electron beams. That was not possible at that time even using best computers available. Plus as I said, measuring/estimating the complex scattered field in real time and actively canceling it is way above even the current technology and we will need at least 7 to 10 years to get there.

So using essentially a version of modified television cathode rays of the time and testing their effects on scattered field and fine tuning them is “NOT that beyond the rest of the world technology”, even at that time. It was accessible to everyone around the world who had an aircraft and a modest industry. Plus For the people in the field such ideas are NOT that novel. We all get them all the time.

About plasma, well there are plenty of soviet and even world war 2 era research exists that essentially details how EM waves interact with plasma. For simplicity plasma is modeled usually as a multi-layered dielectric with parameters depending on electron density, plasma thickness, profile etc. Only recently we have fairly accurate models both analytical and computational. However, still covering, generating and maintaining required plasma profile, along with other host of difficult problems, it is still not very viable option (only partially viable). US experimented with it in the past but so did any moderately industrialized country.

Also use of ferromagnetic based Radar absorbing was even known to Nazi Germany. Even F-22 used them half a century later (find out yourself by researching on google to verify).

Calling it highly futuristic classified technology is just unethical and seems just wrong. Academic research in every country including US and the rest of the world is mostly several years ahead of its actual industrial applications. We can always read and understand where the country will be in next 10 years by just reading such research. Nothing that magical is being made “under highly classified secrete labs”. If that was the case, such magical technology would have already existed. Other countries have and can develop similar stuff what one can do, if they are determined enough. You don’t have to believe it, off course. You can believe magical technologies are being developed by US in “secrete labs”. World has now grown much more mature. Such claims don’t work anymore. Other countries are increasingly catching up and have already caught up with the most advanced. Developing countries like Pakistan may need work ahead but others more developed have reached a stage where they can safeguard themselves by matching technology by technology. Easy accessibility of advanced research in every country has led to demystification of science and technology.

An increasingly large number of informed people no longer believe in such “secrete decades ahead than the rest of the world” nonsense.


The titanium manufacturing and fabrication technology to make SR-71 was stolen from Soviets (google it, its even in the SR-71 documentary) and to make stealth aircraft, the research of the father of stealth technology namely the russian scientist Petr Ufimtsev was stolen by the official technology stealing department of america at that time called "the foreign technology department". His Russian book titled in english "Method of Edge Waves in the Physical Theory of Diffraction" was also machine translated and made available to US scientists. The Russian science and technology was then copied and applied later to Lockheed F-117 Nighthawk.

Now a days NSA does the technology theft for US, though probably the infamous "foreign technology department" still exits. You can read about it from the account given by Lockheed stealth designer himself in the forward of the book "Theory of Edge Diffraction in Electromagnetics" second edition where He shamelessly admits all that. The book is again by same russian namely Petr Ufimtsev. Forward is written by american stealth designer.

This was just to inform such people who want to live in real world and are not mentally slaves of other humans. We are all humans and eventually can reach wherever we want to be depending on the degree of our inner freedom. We can understand what others can. May be now as a country we are messed up, but we will get there in time. Even US has to pass through our phase.

Truth shines and outshines everything else for those who have eyes. The truth is we all have our severe limitation when competing with the rest of the world. Everyone is free to believe their own fabricated reality. Real reality is however independent of "perception engineering".

Realize: Truth is always a constant. You can’t add anything to it nor take away anything from it. In all sense of the way it remains eternally pure.