China's Missile Defense System

Discussion in 'Chinese Defence Forum' started by Martian2, May 26, 2010.

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  1. Martian2
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    Martian2 SENIOR MEMBER

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    The following question is the converse of the implications of a "PLA missile defense system." What about the American missile defense system? The points raised apply equally to the PLA missile defense system.

    Should China worry about U.S. National Missile Defense (i.e. NMD)?

    1) Firstly, NMD doesn't work. There was a recent test failure (see Despite Failed Test, Missile Defense Program Must Continue | The Foundry: Conservative Policy News.).

    2) Secondly, there is no way of knowing whether the entire system will work during an actual war. There is no real confidence in the NMD system because you can't conduct a real test of hundreds of incoming MIRVed missiles that releases thousands of nuclear warheads.

    3) Thirdly, if you detonate a nuclear weapon high above the atmosphere, it will create an EMP to permit the penetration of follow-up attack missiles.

    4) Fourthly, China can use nuclear IRBMs to wipe out the American interceptor base in Alaska. Once the NMD missile base has been destroyed, the shield is gone.

    5) Fifthly, unless the American interceptors can destroy the incoming missiles in the boost or mid-course phase, no current technology can stop incoming nuclear warheads traveling at Mach 10.

    6) Sixthly, MIRVed ICBMs will overwhelm any realistic NMD. For example, twenty ICBMs with 10 MIRVs = 200 warheads. The defender is at a severe disadvantage. The attacker can always build more cheaper MIRVed ICBMs than the defender can build an interceptor rocket for each incoming warhead.

    7) Seventhly, China is building her own NMD. You have a shield. I have a shield. Now, we're even.
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    Martian2 SENIOR MEMBER

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    I think Boeing's Airborne Laser shows that laser-beam weapons against ballistic missiles are not practical.

    It took "two minutes to destroy" the ballistic missile. We have all seen the heat-shield tiles on the space shuttle as it comes in for reentry. An adversary merely has to add some heat-resistant tiles/materials to its ballistic missiles. Think about how many hours it would require for Boeing's Airborne Laser to burn through a space shuttle heat-tile. Laser beam weapons do not look viable.

    You can watch the video at the following link:



    "For the first time the U.S. military has shot down a ballistic missile with an airbourne laser beam. The experiment, conducted off the California coast, was to demonstrate the future of defence technology. From the moment the missile was launched, it took the jumbo-jet mounted laser, just two minutes to destroy. The revolutionary use of laser beams is seen as extremely attractive in missile defens More.. More..e, as it has the potential to attack multiple targets at the speed of light, and is far cheaper than current systems." [Quote is from LiveLeak.com]
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    Martian2 SENIOR MEMBER

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    An optimum solution would be a spinning ablative-armored missile with reasonable thickness. There are others who believe that "ablative coatings" may be an useful counter-measure.

    High Power Rocketry: Airborne ABM system test

    "There are some real problems here, however. Firstly, this missile was known in advance. With all of these tests, the warning time makes them somewhat unrealistic. A real test would have the missile launch window be months long, and the launch should take place without any warning. Further, this system only seems to work in the boost phase - an RV is already very heat resistant, and it would take a HUGE laser to damage one of them. Also, this was a liquid fueled missile. Most serious ballistic missiles will be solid fueled, and thus already very robust. The plane will have to be at least twice as close to a solid rocket booster to cause similar damage, if not closer. Remember that solid rocket motors are insulated to protect the airframe from the heat within. This insulation helps to some extent from the outside in. The best bet may be to weaken the airframe enough to cause a failure. However missiles can be made to spin rapidly, have ablative coatings, or as above some reflective coatings. Thinking back to the Sprint ABM rocket (as I do daily), it would take a building-sized, ground-based laser to even have a chance of catching it in the boost phase.

    It is a bad sign if your billion dollar ABM program can be defeated with a 1 inch layer of cork on a missile!

    With ballistic missiles, the odds are alway tipped towards the offensive weapons. Nothing can replicate the power of a nuclear ABM design, but for some reason this is no longer popular. The most advanced fissile cores are resistant to neutron flux, but the power of a W54 type warhead and hit to kill accuracy combined is enough to destroy any RV... One need not even consider the high power warheads that are in the 100 - 700 KT power range."
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    Martian2 SENIOR MEMBER

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    One countermeasure against an airborne laser is to make a laser-resistant missile (i.e. ablative coating or reflective surface) and/or to spin it and dissipate the heat energy.

    Another approach is to attack the airborne laser platform itself. The airborne laser is humongous and not stealthy. During operation, it emits a giant infrared signature. Using ground-to-air missiles like the S-300 or air-to-air missiles from attack fighters, the airborne laser is vulnerable to being shot down.

    Common sense also dictates that a rival state would build comparable and smaller airborne lasers of their own. By fielding more numerous smaller airborne lasers, the defender can lase the opponent's airborne laser.

    A third approach is to take advantage of natural weather conditions. An attacker may want to wait for cloudy weather (i.e. inhibits laser) across the entire Northern Hemisphere or a severe solar storm (i.e. interferes with electronics).

    There is always the old EMP standby. Launch a nuclear-tipped Nike Hercules-class interceptor missile at an airborne laser. Detonate an EMP at the airborne laser plane and their sensors should be damaged. At a minimum, the atmospheric distortions caused by the thermonuclear blast will disrupt the sensors and targeting of the airborne laser.

    "Military systems must survive all aspects of the EMP, from the rapid spike of the early time events to the longer duration heave signal. One of the principal problems in assuring such survival is the lack of test data from actual high-altitude nuclear explosions. Only a few such experiments were carried out before the LTBT took effect, and at that time the theoretical understanding of the phenomenon of HEMP was relatively poor. No high-altitude tests have been conducted by the United States since 1963."

    Another idea is to build specialized missiles that are laser-resistant to attack airborne lasers. These specialized missiles are built with a small warhead to destroy only a large airborne laser airplane.

    It may also be possible to shoot down airborne lasers with ground-based or sea-based units of attacking lasers.

    In conclusion, airborne lasers are merely another weapon in the toolbox of a country. They are subject to the typical responses of countermeasures, platform attacks, disruptions, weather conditions, and convergent engineering (i.e. everyone knows that China has a laser development program).

    "China advancing laser weapons program
    Technology equals or surpasses U.S. capability
    Posted: November 22, 1999
    1:00 am Eastern

    By Jon E. Dougherty
    © 2010 WorldNetDaily.com

    Not only is the Chinese military advancing rapidly in the field of anti-satellite, anti-missile laser weapon technology, but its technology equals or surpasses U.S. laser weapons capabilities currently under development, informed sources have told WorldNetDaily.

    According to Mark Stokes, a military author specializing in Chinese weapons development, Beijing's efforts to harness laser weapons technology began in the 1960s, under a program called Project 640-3, sanctioned by Chairman Mao Zedong. The Chinese, he said, renamed the project the "863 Program" in 1979, after a Chinese researcher named Sun Wanlin convinced the Central Military Commission "to maintain the pace and even raise the priority of laser development" in 1979.

    Today, Beijing's effort to develop laser technology encompasses over "10,000 personnel -- including 3,000 engineers in 300 scientific research organizations -- with nearly 40 percent of China's laser research and development (R & D) devoted to military applications," Stokes wrote in an analytical paper provided to WorldNetDaily.

    China's "DEW (Directed Energy Weapons) research (is) part of a larger class of weapons known to the Chinese as 'new concept weapons' (xin gainian wuqi), which include high power lasers, high power microwaves, railguns, coil guns, (and) particle beam weapons," Stokes said. "The two most important organizations involved in R&D of DEW are the China Academy of Sciences and the Commission of Science, Technology and Industry for National Defense (COSTIND)."

    To underscore Beijing's fixation with laser weaponry, the Hong Kong Standard reported Nov. 15 that the Chinese have developed a laser-based anti-missile, anti-satellite system.

    "China's system shoots a laser beam that destroys the [guidance systems] and causes the projectile to fall harmlessly to the ground," the paper said.

    The report also noted that Beijing had "conducted tests of its new technology since August 1999," and said the system was 'similar to the laser defense system technology being developed by the U.S. Air Force.'"
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  5. Martian2
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    Martian2 SENIOR MEMBER

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    What does a laser-resistant missile look like?

    1) The casing may be built from expensive, but lightweight, titanium. "Layers of titanium and other metals" provide excellent heat-resistance.

    "HOT TILE - Example of a new type of heat-resistant tile, composed of layers of titanium and other metals, which might eventually replace tiles now on the space shuttles."

    2) Use "pyrolytic graphite or carbon composites." This makes sense. Diamonds are a form of carbon. Diamonds are heat resistant.

    "Laser hardened missile casing
    United States Patent 4686128

    A thermally protective covering for a structure includes a thermally ablating layer comprising a nonporous ablative material comprising pyrolytic graphite or carbon composites bonded to a rigid, nonporous insulating layer comprising composites having high strength fibers in an insulating matrix. The insulating layer is bonded to the casing of the structural element to be protected. More preferably, the thermally ablating layer comprises pyrolytic graphite and the rigid, nonporous insulating member comprises silica phenolic. The ablating layer is bonded to the insulating layer with a high temperature graphite cement having adhesive properties to at least 3000° K. In a preferred embodiment, means are provided for venting pyrolysis gas produced during exposure of the ablating layer to a high energy laser."

    3) Expand the use of proven materials, which are used to contain the high-temperatures near the rocket motor, to the rest of the missile.

    "Thermoplastic para-polyphenylene sulfide, high temperature-resistant rocket motor cases
    United States Patent 5380570

    Para-polyphenylene sulfide, a non-composite, ultrahigh-temperature-resist, thermoplastic resin, is employed for the manufacture of interceptor motor cases. The thermoplastic resin, para-polyphenylene sulfide, has a combination of properties which are of particular interest in the fabrication of interceptor rocket motor cases. Para-polyphenylene sulfide in ribbonized forth is wound directly onto the required mandrel and then fused into a solid mass. The fused, solid mass has the properties which enables it to serve as both insulator and motor case material. The manufacture of a combination insulated motor case is achieved by the following method: The equipment, first, involves the fabrication of a breakout mandrel by one of several methods. The para-polyphenylene sulfide is ribbonized by extrusion and wound down on the breakout mandrel to the required thickness and fused into a solid mass by heating to its melt temperature of about 285° C. The breakout mandrel is removed to release the interceptor rocket motor case which functions as both insulator and interceptor rocket motor case material."

    4) Use new lightweight and heat-resistant Aerogel material in a layer within the missile casing.

    "JPL's newest version of Aerogel is 99.8 percent air and is a stiff foam made from silicon dioxide and sand. Its density is just 3 milligrams per cubic centimeter and it pressure thousands of times greater than its own mass. Its melting point is 2,200 degrees Fahrenheit (1,200 degrees Centigrade)."

    A laser-resistant missile may include a mixture of the aforementioned ideas. Heat resistance is important because the airborne laser only has a limited amount of chemical fuel for the laser. Instead of two minutes, if it requires 20 minutes, there may not be sufficient time or chemical fuel on the airplane to destroy the missile before warhead release.
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    Martian2 SENIOR MEMBER

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    There seems to be serious limitations to Boeing's Airborne Laser. The range is extremely limited at "200-250 km." It is not possible to fly an entire fleet of Airborne Lasers within 250 km of the launch sites in Russia or China to shoot down ICBMs in their boost phase. The Boeing 747 jumbo jet that houses the Airborne Laser is an easy target for a S-300 or HQ-9 missile.

    How Real Is The Threat Of Laser Weapons

    "What is the ALTB's potential? Although there is no exhaustive information on the February 12 tests, some conclusions can be drawn on the basis of available reports.

    The Boeing YAL-1 Airborne Laser (ABL) weapons system has three laser systems, namely, a Track Illuminator Laser (TILL) for illuminating the target and adjusting the parameters of the laser weapon's optical system, a Beacon Illuminator Laser (BILL) for reducing atmospheric aberration, and the six-module High-Energy Laser (HEL) weapon system.

    The YAL-1 can hit ballistic missiles during their boost phase and has a range of 200-250 km. The effective range is limited by the laser unit's power, the laser beam's atmospheric dissipation, atmospheric aberration affecting siting accuracy and the laser-beam gas breakdown effect which has not yet been eliminated. Moreover, an excessively powerful laser unit could overheat the fuselage and cause the plane to crash.

    These factors and the system's low rate of fire currently make it possible only to intercept individual missiles at short range. It appears that such systems will be unable to neutralize an all-out nuclear strike in the next 20-30 years.

    Speaking of a hypothetical Russian-U.S. conflict, airborne laser weapons would have to be deployed in Russian air space in order to be able to intercept Russian missiles in their boost phase and during the separation of their multiple independently targetable reentry vehicles (MIRVs). In fact, they would have only 3-5 minutes to accomplish this objective.

    However, even Russia's problem-ridden air-defense system would not allow a B-747 to roam free in national air space.

    Airborne laser weapons present a greater threat to strategic ballistic missile submarines which either patrol Russian territorial waters or international waters. However, there is one limitation. As the submarines spend most of their time underwater, laser-carrying aircraft could not quickly reach the optimal firing position necessary for a successful missile interception.

    Consequently, this project's current version threatens only countries such as Iran or North Korea which have a small territory and are therefore unable to deploy missile bases far from their borders."

    [​IMG]
    "At 8:44 p.m. PST Feb. 11, a short-range threat-representative ballistic missile was launched from an at-sea mobile launch platform. Within seconds, the Airborne Laser Testbed used onboard sensors to detect the boosting missile and used a low-energy laser to track the target.

    The Airborne Laser Testbed then fired a second low-energy laser to measure and compensate for atmospheric disturbance. Finally, the Airborne Laser Testbed fired its megawatt-class High Energy Laser, heating the boosting ballistic missile to critical structural failure. The entire engagement occurred within two minutes of the target missile launch, while its rocket motors were still thrusting.

    This was the first directed energy lethal intercept demonstration against a liquid-fuel boosting ballistic missile target from an airborne platform. The revolutionary use of directed energy is very attractive for missile defense, with the potential to attack multiple targets at the speed of light, at a range of hundreds of kilometers, and at a low cost per intercept attempt compared to current technologies.

    Less than one hour later, a second solid fuel short-range missile was launched from a ground location on San Nicolas Island, Calif., and the Airborne Laser Testbed successfully engaged the boosting target with its High Energy Laser, met all its test criteria, and terminated lasing prior to destroying the second target. The Airborne Laser Testbed destroyed a solid fuel missile, identical to the second target, in flight on February 3, 2010."
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  7. Martian2
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    Martian2 SENIOR MEMBER

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    https://www.strategypage.com/htmw/htecm/20100203.aspx

    1) China also has AESA radar technology (see http://www.defence.pk/forums/china-...52c-aegis-class-warships-ocean-dominance.html). It is only a matter of time (e.g. 5, 10, 15, or 20 years; take your pick) before China has roughly equivalent AESA radar on fighter planes.

    2) I don't know enough about radar. However, countermeasures may be designed against a microwave attack. A "Faraday cage" blocks electrical energy. There might be a similar analogue for microwave energy. An obvious countermeasure is radiation hardening of missile electronics.

    3) I don't know if a long-range microwave weapon is feasible. Looking at the electromagnetic spectrum (see picture below), microwave energy is extremely weak in comparison to visible light. We know that lasers aren't that great for shooting down missiles. The latest Boeing ABL (i.e. Airborne Laser) test required over two minutes to damage a ballistic missile. Furthermore, the ABL was using the chemical energy output available from a massive tank carried on a giant Boeing 747 airplane. The chemical energy output available to power a microwave/"electromagnetic beam" weapon from a fighter jet is extremely tiny in comparison.

    4) Microwave energy is a form of electromagnetic energy. It has the same shortcomings as a laser-based weapon. Microwave weapons are useless when it's foggy or rains (e.g. the water moisture absorbs the electromagnetic energy; it's like heating a cup of water in a microwave oven). You also have refraction problems. Also, as a countermeasure, scientists can probably design ablative armor tuned to the frequencies of microwave radiation to protect attack missiles.

    5) Another countermeasure is to place the sensitive electronics within a metamaterial that is invisible to microwave energy. China also possesses very advanced metamaterial technology.

    Metamaterial - Wikipedia, the free encyclopedia
    "In October 2006, a US-British team of scientists created a metamaterial which rendered an object invisible to microwave radiation. As the visible spectrum ..."

    Chinese scientists create metamaterial black hole
    "Oct 16, 2009 ... (PhysOrg.com) -- Two physicists in China have used metamaterials to create the first artificial electromagnetic black hole."

    In conclusion, an arms race is always exciting to watch.

    [​IMG]
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    Martian2 SENIOR MEMBER

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    You should expand my title to the "fog, rain, and atmosphere" guy. The directed AESA beam weapon sounds similar to a MASER (Microwave Amplification by Stimulated Emission of Radiation). The part that I'm uncertain about is whether the electromagnetic waves from the AESA radars are coherent or not. In any case, any electromagnetic weapon (e.g. laser, maser, or AESA-based) will have a very limited range at sea level because the thick atmosphere (e.g. air density) absorbs electromagnetic energy. I remember my college physics professor saying that if you fire a very powerful laser at sea level then the physics equations show that the energy will be dissipated by the atmosphere when it reaches the other end of the tennis court.

    Electromagnetic beam weapons face beam energy dissipation and focusing problems at sea-level due to the thick atmosphere and unpredictable fluctuations in atmospheric density. The two big problems are that the atmosphere will absorb the beam energy (e.g. similar to pumping a lot of heat energy into a giant heat-sink or iceberg) and distort the direction of the beam, which makes continuous targeting a nightmare (e.g. you've seen the shimmering atmospheric distortions with your naked eye when the heat rises from the ground in a hot desert). Also, every night, you see the stars twinkle. That is continuous atmospheric distortion.

    [​IMG]
    Giraffe in heat haze.

    The following article from Global Security examines the multitude of problems with all beam weapons. I think it may be premature to declare that AESA beam weapons have overcome the problems of maintaining targeting, energy output requirement, energy absorption and distortion by thick sea-level atmosphere, and my favorite "it could be foggy or rainy today." Scientists have been working on these problems for decades and I haven't really heard of good "conceptual" (e.g. new theoretical) methods to overcome these long-standing problems. I'm not saying that it can't be done, however what has changed in the last few years to allow them to overcome all of these physics problems that no one could solve for decades? The last paragraph (e.g. prior to "sources and resources") in the Global Security article informs us that scientists were still scratching their heads in 2007.

    Directed Energy Weapons

    "Directed Energy Weapons

    A Directed Energy Weapon is a system using directed-energy primarily as a direct means to damage or destroy enemy equipment, facilities, and personnel. Directed energy offers promise as a transformational “game changer” in military operations, able to augment and improve operational capabilities in many areas. Yet despite this potential, years of investment have not resulted in any operational systems with high energy laser capability. The lack of progress is a result of many factors from unexpected technological challenges to a lack of understanding of the costs and benefits of such systems. Ultimately, as a result of these circumstances, interest in such systems has declined over the years.

    Initially, the American projects were developed as separate entities, with a relatively loose interservice coordination. In 1978, however, the Department of Defense organized an Office of Directed Energy Technology to coordinate the development of beam weapons, and the Pentagon established the Particle Beam Technology Study Group, composed of 53 Defense Department and US scientific community personnel.

    Through fiscal year 1993, SDIO spent about $4.9 billion over 9 years of a planned $6.7 billion for directed energy research and development, or about $800 million less than the 1984 plan specified was needed over 6 years. SDIO said that this was nearly all of the national effort in high-power directed energy weapons. SDIO also said that this under funding becomes larger if it is recognized that stretched-out programs cost more than efficiently funded programs and that dollars spent in years following the planned years had been degraded by inflation. In the early years of SDI, the directed energy funding made up nearly a quarter of SDI’s total funding. Annual funding peaked at $827 million in fiscal year 1983 and subsequently decreased to $162 million in fiscal year 1993.

    A particle beam transmits a stream of high-energy atomic particles which can destroy or neutralize a target. The particles may have a positive or negative charge or may be neutral. In each case the particles are injected into some type of medium, normally an electron beam, and accelerated to near-light (relativistic) velocities. The medium, called a plasma when combined with the particles, can then be aimed at the desired target. For example, a negatively charged electron beam similar to those in a television picture tube can be fired through a gas or other source of positive atomic particles such as protons. These particles are swept along by the oppositely charged electron beam. Since the electron beam is relativistic, the positive particles are accelerated to relativistic velocities. The almost massless electrons can then be removed from the beam, leaving a stream of relatively heavy atomic particles.

    This stream of particles traveling at a relativistic velocity is a tremendous energy emission. Einstein's famous formula, E = mc2, shows the relationship between energy, mass, and the velocity of light. For example, it demonstrates why a very small object, such as an atomic particle, moving at a relativistic velocity will have a very high energy potential and why it will impart an enormous amount of energy to whatever it strikes.

    Particle beams are not a steady stream of energy but rather are a series of pulses. Like a bolt of lightning, each pulse is only a few millionths of a second long and discharges great quantities of energy which can have a variety of effects on a target, depending on the level of energy. For example, a beam of five seconds' duration with an energy of 25 megajoules would have the explosive equivalent of 50 pounds of TNT. Such an explosive force could have devastating effects on an intercontinental ballistic missile's (ICBM) reentry vehicle or its booster during the powered portion of flight. Additionally a selected target could be totally disintegrated, by making its molecular structure unstable through the enormous energy transfer. Similarly, a target could become super heated and vaporize. A beam with a lower energy level could pass through a target, such as an ICBM reentry vehicle, causing electrical and magnetic disruptions in its electronic 5components. The lethality and relativistic nature of beam weapons make them especially suitable for antiballistic missile (ABM) applications.

    A Neutral Particle Beam (NPB) weapon produces a beam of near-light-speed-neutral atomic particles by subjecting hydrogen or deuterium gas to an enormous electrical charge. The electrical charge produces negatively charged ions that are accelerated through a long vacuum tunnel by an electrical potential in the hundreds-of-megavolt range. At the end of the tunnel, electrons are stripped from the negative ions, forming the high-speed-neutral atomic particles that are the neutral particle beam. The NPB delivers its kinetic energy directly into the atomic and subatomic structure of the target, literally heating the target from deep within. Charged particle beams (CPB) can be produced in a similar fashion, but they are easily deflected by the earth’s magnetic field and their strong electrical charge causes the CPB to diffuse and break apart uncontrollably. Weapons-class NPBs require energies in the hundreds of millions of electron volts and beam powers in the tens of megawatts. Modern devices have not yet reached this level.

    In 1951, Charles Townes and co-workers discovered stimulated emission in ammonia, which led to the development of a maser (microwave amplification by stimulated emission). They were encouraged by AFOSR to extend the work to shorter wavelength all the way to the optical region. Ten years later, in 1961, Ted Maiman (Hughes Aircraft Company) announced the development of a laser (light amplification by stimulated emission). The use of lasers in numerous applications eventually led to more powerful devices.

    The long-cited advantages of high-energy lasers [HEL] include speed of light response, precision effects, limiting collateral damage, deep magazines, and low cost per kill. High-energy lasers have two characteristics that make them particularly valuable for effects-based application: they are extremely fast and extremely precise. The laser begins its attack within seconds of detecting its target and completes its destruction a few seconds later. This means the operator has time for multiple shots if needed to destroy the target or engage multiple targets.

    Lasers can be built as either continuous wave (CW) or pulsed devices. CW laser effects are generally described in terms of power density on target in W/m2; pulsed laser effects are described in terms of energy density on target in J/m. For the space-earth geometry multimegawatt power is required for a CW weapons laser and hundreds to thousands of joules of energy per pulse is required for a pulsed weapons laser (depends on pulse length and pulse repetition frequency).

    The laser beam delivers its energy to a relatively small spot on the target—typically a few inches in diameter. The incident intensity is sufficient to melt steel. Typical melt-through times for missile bodies are about 10 seconds. But if the heated area is under stress from aerodynamic or static pressure loads, catastrophic failure can occur more quickly. The beam can attack specific aim points on a missile that are known to be vulnerable; for example, pressurized fuel tanks or aerodynamic control surfaces. The laser weapon design, therefore, must include the ability to "see" and identify specific aim points, to put the beam on that aim point and hold it for a few seconds, and finally, to determine when the desired effect on the target has been achieved.

    There are four fundamental approaches to high- and medium-power laser energy: chemical lasers, solid-state lasers, fiber lasers, and free electron lasers.

    * Chemical lasers can achieve continuous wave output with power reaching to multi-megawatt levels. Examples of chemical lasers include the chemical oxygen iodine laser (COIL), the hydrogen fluoride (HF) laser, and the deuterium fluoride (DF) laser. There is also a DF-CO 2 (deuterium fluoride-carbon dioxide) laser.
    * Diode-pumped solid-state (DPSS) lasers operate by pumping a solid gain medium (for example, a ruby or a neodymium-doped YAG crystal) with a laser diode.
    * Combining the outputs of many fiber lasers (100 to 10,000) is a possible way to achieve a highly efficient HEL. Fiber-laser technology continues to advance. At 1 ??m, 200 W amplifiers are available commercially, and > 500 W has been demonstrated in the lab.
    * Free-electron lasers (FELs) are unique lasers in that they do not use bound molecular or atomic states for the lasing medium. FELs use a relativistic electron beam (e-beam) as the lasing medium. Generating the e-beam energy requires the creation of an e-beam (typically in a vacuum) and an e-beam accelerator. This accelerated e-beam is then injected into a periodic, transverse magnetic field (undulator). By synchronizing the e-beam/electromagnetic field wavelengths, an amplified electromagnetic output wave is created.

    Years of major investment in chemical lasers produced megawatt-class systems that could have a wide range of applications. However, size, weight, and logistics issues limit them to integration on large platforms, such as the 747 used for the ABL program, or fixed ground applications such as the Ground-Based Laser for Space Control. As a consequence, interest in these systems and expectations of progress has significantly decreased.

    The laser weapon delivery system is a complicated one, consisting of many elements grouped as subsystems. Two parts to the system involve equipment used in the operation of the laser weapon: (1) beam generation or laser source; and (2) supporting technologies such as acquisition, pointing, and tracking (including fast beam-slewing equipment, adaptive optics, and reflective mirrors). To develop an effective laser system two other important areas have to be considered: (1) beam-target interaction/lethality science and validation; and (2) modeling and simulation including theoretical calculations and/or computer models.

    Key issues that have an impact on all initiatives include pointing and tracking accuracy, beam control, and beam propagation in a battlefield environment or during poor weather conditions
    . In the case of laser weapons, lethality effects against a variety of targets must also be clearly understood.

    Pointing and tracking accuracy is the ability to point the laser beam to the desired aimpoint and to maintain that aimpoint on the target. To achieve the status of a precision-aimed weapon, laser weapon systems will require pointing and tracking accuracies in the 10 to 100 nanoradian range for systems in low earth orbit.

    Beam control refers to forming and shaping the beam. Depending on the nature of the specific laser, beam control can include initial processing of the beam to shape it and eliminate unwanted off-axis energy, or can include wavefront shaping and/or phase control. For visible and near-infrared lasers, the frequencies under study for use at long range, optics in the four to 20 meter diameter should suffice for a system in low earth orbit.

    Beam propagation describes the effects on the beam after it leaves the HEL output aperture and travels through the battlefield environment to the target. Optical stability of the platform and beam interactions with the atmosphere, both molecules and aerosol particles, primarily determine the laser beam quality at the target. Beam quality is a measure of how effective the HEL is in putting its light into a desired spot size on the target.

    Atmospheric and propagation effects on HEL performance requires expanded efforts to measure and understand low-altitude, “thick-air” atmospheric effects. Primary concerns include the effects of atmospheric turbulence and aerosol scattering on the HEL beam. Nonlinear propagation effects such as thermal blooming can also have important effects for many applications. Technical remedies are available to deal with atmospheric turbulence, but much more understanding is needed, as is the ability to predict and measure atmospheric turbulence. Non-linear propagation effects require detailed analyses and experiments. They also require beam control concepts to ameliorate the negative effects. No such analyses or experiments exist for multi-pulse systems.

    Lethality defines the total energy and/or fluence level required to defeat specific targets. The laser energy must couple efficiently to the target, and it must exceed a failure threshold that is both rate dependent and target-specific. Laser output power and beam quality are two key factors for determining whether an HEL has sufficient fluence to negate a specific target.

    By 2007 the focus was on solid state lasers with the promise of providing for smaller, lighter systems with deep magazines. However, the current goal for solid state laser development would provide a power level more than an order of magnitude lower than current chemical lasers. While beam quality and other factors can compensate for some of the difference in power level, there is currently little investment in those aspects. Further, these cannot make up the delta in power of chemical vs. solid state lasers. The near-term projection for solid state lasers is a power level closer to two orders of magnitude below that of chemical lasers.

    Sources and Resources

    Directed Energy/Space-Based Laser: Ballistic Missile Defense Organization (BMDO) The Directed Energy (DE) program continues the process of integrating high power chemical laser components and technologies developed over the past 10 years specifically for the ballistic missile defense boost phase intercept mission.

    High Energy Laser Systems Test Facility The High Energy Laser Systems Test Facility (HELSTF) is located at White Sands Missile Range, New Mexico. HELSTF has been managed by the U.S. Army Space and Strategic Defense Command (USASSDC) since October 1990. HELSTF is designated as the Department of Defense (DoD) National Test Facility for high energy laser test and evaluation. HELSTF is the home of the Mid Infrared Advanced Chemical Laser (MIRACL), the United States' most powerful laser.

    SEALITE Beam Director (SLBD) The SEALITE Beam Director (SLBD) is mounted on top of Test Cell 1. It consists of a large aperture (1.8 meter) gimbaled telescope and optics to point the MIRACL or other laser beam onto a target. The high power clear aperture is 1.5 meters. The remaining 0.3 meters is normally reserved for a tracker using the outer annulus of the primary mirror. The system is extremely agile and capable of high rotation and acceleration rates"
    Last edited: May 27, 2010
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  9. gambit
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    gambit PROFESSIONAL

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    :lol: The Chinese fanboys are nervous at the progress the American NMD program has made.
  10. Martian2
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    Martian2 SENIOR MEMBER

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    China: Missile defense system test successful - USATODAY.com

    "China: Missile defense system test successful

    Posted 1/11/2010 8:08 PM

    BEIJING (AP) — China announced that its military intercepted a missile in mid-flight Monday in a test of new technology that comes amid heightened tensions over Taiwan and increased willingness by the Asian giant to show off its advanced military capabilities.

    The official Xinhua News Agency reported late Monday that "ground-based midcourse missile interception technology" was tested within Chinese territory.

    "The test has achieved the expected objective," the three-sentence report said. "The test is defensive in nature and is not targeted at any country."

    Monday's report follows repeated complaints in recent days by Beijing over the sale by the U.S. of weaponry to Taiwan, including PAC-3 air defense missiles. These sales are driven by threats from China to use force to bring the island under its control, backed up by an estimated 1,300 Chinese ballistic missiles positioned along the Taiwan Strait.

    Communist-ruled China split with Taiwan amid civil war in 1949 and continues to regard the self-governing democracy as part of its territory. Beijing has warned of a disruption in ties with Washington if the sale goes ahead, but has not said what specific actions it would take.

    In Washington, the U.S. Defense Department said it had no notice before the Chinese test but that the United States does not consider it related to U.S. arms sales to Taiwan.

    "We did not receive prior notification of the launch," Maj. Maureen Schumann, a Pentagon spokeswoman, said. "We detected two geographically separated missile launch events with an exo-atmospheric collision also being observed by space-based sensors. We are requesting information from China regarding the purpose for conducting this interception as well as China's intentions and plans to pursue future types of intercepts."

    China's military is in the middle of a major technology upgrade, spurred on by double-digit annual percentage increases in defense spending. Missile technology is considered one of the People's Liberation Army's particular strengths, allowing it to narrow the gap with the U.S. and other militaries that wield stronger conventional forces.

    Xinhua did not further identify the system tested, although China is believed to be pursuing a number of programs developed from anti-aircraft systems aimed at shooting down stealth aircraft and downing or disabling cruise missiles and precision-guided weapons.

    Such programs are shrouded in secrecy, but military analysts say China appears to have augmented its air defenses with homemade technologies adapted from Russian and other foreign weaponry. China purchased a large number of Russian surface-to-air missiles during the 1990s and has since pressed ahead with its own HQ-9 interceptor, along with a more advanced missile system with an extended range.

    Foreign media reports in 2006 said Beijing had tested a surface-to-air missile in the country's remote northwest with capabilities similar to the American Patriot interceptor system. According to South Korea's Dong-A Ilbo newspaper, the test involved the detection and downing of both a reconnaissance drone and an incoming ballistic missile by an interceptor, adding that it appeared to mark the official launch of China's indigenous interceptor unit.

    "There is an obvious concern in Beijing that they need an effective anti-ballistic missile defense in some form," said Hans Kristensen, an expert on the Chinese military with the Federation of American Scientists.

    Staging a successful test "shows that their technology is maturing," Kristensen said.

    The 2009 Pentagon report on China's military says the air force received eight battalions of upgraded Russian SA-20 PMU-2 surface-to-air missiles since 2006, with another eight on order. The missiles have a range of 125 miles (200 kilometers) and reportedly provide limited ballistic and cruise missile defense capabilities.

    Such interceptor missiles are believed to be deployed near major cities and strategic sites such as the massive Three Gorges Dam, but they could also be used to protect China's own ballistic missile batteries that would themselves become targets in any regional conflict.

    Such interceptors would be of relatively little use against U.S. cruise missiles, although they could be effective against ballistic missiles deployed by Russia or India, China's massive neighbor to the south with which it has a growing military rivalry and lingering territorial disputes.

    Monday's report continues a growing trend of greater transparency over China's new military technologies typified by last year's striking Oct. 1 military parade marking the 60th anniversary of the founding of the communist state. Large numbers of missiles were displayed in the show, including ICBMs, together with tanks, amphibious craft and latest-generation jet fighters.

    China's anti-ship cruise and ballistic missiles — capable of striking U.S. Navy aircraft carrier battle groups and bases in the Pacific — have drawn the most attention from analysts in recent months.

    Military displays and announcements of successful tests help build public pride in the military's rising capabilities and bolster support for rising defense spending that increased by almost 15% last year to $71 billion. The figure is thought by many analysts to represent only a portion of total defense spending, although it still amounts to only a fraction of the U.S. military budget.

    Meanwhile, showing off such capabilities also helps put adversaries on notice, Kristensen said.

    "It's the new Chinese way to signal that they are now able to do these things," he said.

    Copyright 2010 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed."
    Last edited: May 27, 2010
  11. Martian2
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    Martian2 SENIOR MEMBER

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    The United States is not that far ahead of China in NMD (i.e. national missile defense) technology.

    Air Force: Test missile misses its Pacific target | World news | guardian.co.uk

    "Air Force: Test missile misses its Pacific target

    AP foreign, Monday February 1 2010

    VANDENBERG AIR FORCE BASE, Calif. (AP) — The Air Force says a missile-intercept test failed when a long-range missile launched from California missed a target missile launched from a Pacific island because of radar problems.

    A statement posted on the Vandenberg Air Force Base Web site says the target missile was launched from the Kwajalein Atoll in the Marshall Islands on Sunday at about 3:40 p.m. and the long-range interceptor missile was launched from California's central coast shortly after.

    The statement says both missiles launched and flew without trouble but the system's sea-based X-band radar did not perform as expected and the interceptor missed its target.

    The statement says officials from the Missile Defense Agency that conducted the test will conduct an extensive investigation to determine the cause of the failure."
    Last edited: May 27, 2010
  12. applesauce
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    so then can you make a argument that the NMD are very effective to the point where its cheaper to defend against MIRV'ed missiles than to makes more missiles?
  13. Jazzbot
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    :blink::blink::blink::blink:
  14. Speeder 2
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    Speeder 2 FULL MEMBER

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    Gee, martian 2, are you writing a thesis? :lol:

    Good stuff! :tup:
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  15. gambit
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    gambit PROFESSIONAL

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    What is happening here is deceit. Simple as that. The National Missile Defense program is not static. It will continue to test and to have failures and make progress. The deceit is that a 'snapshot' in time of the program is taken and is presented as if the program has reached its technical limits.

    To quote MIT's Bill Delaney...

    MIT Lincoln Laboratory: News: William Delaney and Eric Evans appointed to the Defense Science Board
    ...When he was asked about the feasibility of an NMD-like program...

    All the items Delaney listed are, in a manner of speaking, against 'known' threats. The characteristics of these threats are constant and predictable as they are defined by nature itself. A ballistic missile is a manmade threat but even so, this threat's characteristics are also defined and governed by nature's laws and therefore it can be countered.

    For example...

    If a MIRV-ed bus is targeting multiple ground points, then assuming we have a functional area defense system like the Patriot or THAAD or the Aegis Ballistic Missile Defense System, each ground defense station can attempt terminal phase intercept as designed. But if a MIRV-ed bus is used against a single target, then there is a motion control issue. The bus would be in a ballistic trajectory and all releases would be in that trajectory but at different points. Each release must be sufficiently far apart -- timed interval -- that the warheads do not interfere or even destroy each other. It is to the absurd that an attacker would send thousands or hundreds of warheads against a single target. Ten MIRVs is more realistic but even that is highly speculative. That mean that as long as the defense is able to distinguish several MIRVs in a descent, the defense will be able to launch several interceptors.
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