Boeing YAL-1
The Boeing YAL-1 Airborne Laser Testbed, (formerly Airborne Laser) weapons system is a megawatt-class chemical oxygen iodine laser
Chemical oxygen iodine laser
Chemical oxygen iodine laser, or COIL, is an infrared chemical laser. As the beam is infrared, it cannot be seen with the naked eye. It is capable of output power scaling up to megawatts in continuous mode...

 (COIL) mounted inside a modified Boeing 747-400F. It is primarily designed as a missile defense
Missile defense
Missile defense is a system, weapon, or technology involved in the detection, tracking, interception and destruction of attacking missiles. Originally conceived as a defence against nuclear-armed Intercontinental ballistic missiles , its application has broadened to include shorter-ranged...

 system to destroy tactical ballistic missile
Tactical ballistic missile
A tactical ballistic missile is a ballistic missile designed for short-range battlefield use. Typically, range is less than . Tactical ballistic missiles are usually mobile to ensure survivability and quick deployment, as well as carrying a variety of warheads to target enemy facilities, assembly...

s (TBMs), while in boost phase
Boost phase
The boost phase is the portion of the flight of a ballistic missile or space vehicle during which the booster and sustainer engines operate until it reaches peak velocity. This phase can take 3 to 4 minutes , the altitude at the end of this phase is 150–200 km, and the typical burn-out speed...

. The aircraft was designated YAL-1A in 2004 by the U.S. Department of Defense
United States Department of Defense
The United States Department of Defense is the U.S...


The YAL-1 with a low-power laser was test-fired in flight, at an airborne target in 2007. A high-energy laser was used to intercept a test target in January 2010, and the following month, successfully destroyed two test missiles.


The Airborne Laser Laboratory, a less-powerful prototype installed in a Boeing NKC-135A
Boeing NC-135
|-See also:- External links :...

, shot down several missiles in the 1980s.

The Airborne Laser program was initiated by the US Air Force
United States Air Force
The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...

 in 1996 with the awarding of a product definition risk reduction contract to Boeing's ABL team. In 2001, the program was transferred to the MDA and converted to an acquisition program.

The development of the system is being accomplished by a team of contractors. Boeing Defense, Space & Security provides the aircraft, the management team and the systems integration processes. Northrop Grumman
Northrop Grumman
Northrop Grumman Corporation is an American global aerospace and defense technology company formed by the 1994 purchase of Grumman by Northrop. The company was the fourth-largest defense contractor in the world as of 2010, and the largest builder of naval vessels. Northrop Grumman employs over...

 is supplying the COIL, and Lockheed Martin
Lockheed Martin
Lockheed Martin is an American global aerospace, defense, security, and advanced technology company with worldwide interests. It was formed by the merger of Lockheed Corporation with Martin Marietta in March 1995. It is headquartered in Bethesda, Maryland, in the Washington Metropolitan Area....

 is supplying the nose turret and the fire control system.

In 2001, a retired Air India
Air India
Air India is the flag carrier airline of India. It is part of the government of India owned Air India Limited . The airline operates a fleet of Airbus and Boeing aircraft serving Asia, Australia, Europe and North America. Its corporate office is located at the Air India Building at Nariman...

 747-200 was acquired by the Air Force, and trucked without its wings from the Mojave Airport
Mojave Spaceport
thumb|right|235px|A retired [[Boeing 767-200]] that flew for [[Ansett Australia]] being cut open for scrap at Mojave AirportThe Mojave Air and Space Port , also known as the Civilian Aerospace Test Center, is located in Mojave, California, at an elevation of...

 to Edwards Air Force Base
Edwards Air Force Base
Edwards Air Force Base is a United States Air Force base located on the border of Kern County, Los Angeles County, and San Bernardino County, California, in the Antelope Valley. It is southwest of the central business district of North Edwards, California and due east of Rosamond.It is named in...

 where the airframe was incorporated into the System Integration Laboratory (SIL) building at Edwards' Birk Flight Test Center, to be used to fit check and test the various components. The SIL was built primarily to test the COIL at a simulated operational altitude, and during that phase of the program, the laser was operated over 50 times, achieving lasing durations representative of actual operational engagements. These tests fully qualified the system so that it could be integrated into the actual aircraft. Following the completion of the tests, the laboratory is being dismantled, and the 747-200 fuselage is being removed.

Boeing completed initial modifications to a new 747-400F off the production line in 2002, culminating in its first flight on July 18, 2002 from Boeing's Wichita, Kansas
Wichita, Kansas
Wichita is the largest city in the U.S. state of Kansas.As of the 2010 census, the city population was 382,368. Located in south-central Kansas on the Arkansas River, Wichita is the county seat of Sedgwick County and the principal city of the Wichita metropolitan area...

 facility. Ground testing of the COIL
Chemical oxygen iodine laser
Chemical oxygen iodine laser, or COIL, is an infrared chemical laser. As the beam is infrared, it cannot be seen with the naked eye. It is capable of output power scaling up to megawatts in continuous mode...

 resulted in its successful firing in 2004. The YAL-1 was assigned to the 417th Flight Test Squadron Airborne Laser Combined Test Force at Edwards AFB.


Besides the COIL, the system also includes two kilowatt-class Target Illuminator Lasers for target tracking. On March 15, 2007, the YAL-1 successfully fired this laser in flight, hitting its target. The target was an NC-135E
Boeing NC-135
|-See also:- External links :...

 Big Crow test aircraft that has been specially modified with a "signboard" target on its fuselage. The test validated the system's ability to track an airborne target and measure and compensate for atmospheric distortion.

The next phase in the test program involved the "surrogate high-energy laser" (SHEL), a stand-in for the COIL, and will demonstrate the transition from target illumination to simulated weapons firing. The COIL system was installed in the aircraft and undergoing ground testing by July 2008.

In an April 6, 2009 press conference, the Secretary of Defense Robert Gates recommended the cancellation of the planned second ABL aircraft and said that the program should return to a Research and Development effort. "The ABL program has significant affordability and technology problems and the program’s proposed operational role is highly questionable," Gates said in making the recommendation.

There was a test launch just off the coast of California on June 6, 2009. If successful the new Airborne Laser Aircraft could be ready for operation by 2013. On August 13, 2009 the first in-flight test of the YAL-1 culminated with a successful firing of the SHEL at an instrumented test missile.

The U.S. Missile Defense Agency (MDA) on August 18, 2009 successfully fired the high-energy laser aboard the aircraft in flight for the first time. The YAL-1 took off from Edwards Air Force Base and fired its high-energy laser while flying over the California High Desert. The laser was fired into an onboard calorimeter, which captured the beam and measured its power.

In January 2010, the high-energy laser was used in-flight, to intercept, although not destroy, a test Missile Alternative Range Target Instrument (MARTI) in the boost phase of flight. On February 11, 2010 in a test at Point Mugu Naval Air Warfare Center-Weapons Division Sea Range off the central California coast, the system successfully destroyed a liquid-fuel boosting ballistic missile. Less than an hour after that first missile had been destroyed, a second missile—a solid-fuel design—had, as announced by the MDA, been "successfully engaged", but not destroyed, and that all test criteria had been met. The MDA announcement also noted that ABL had destroyed an identical solid-fuel missile in flight eight days earlier. This test was the first time that a directed-energy system destroyed a ballistic missile in any phase of flight. It was later reported that the first February 11 engagement required 50% less dwell time than expected to destroy the missile, the second engagement on the solid-fuel missile, less than an hour later, had to be cut short before it could be destroyed because of a "beam misalignment" problem.

Recent developments

Secretary of Defense
United States Secretary of Defense
The Secretary of Defense is the head and chief executive officer of the Department of Defense of the United States of America. This position corresponds to what is generally known as a Defense Minister in other countries...

Robert Gates
Dr. Robert Michael Gates is a retired civil servant and university president who served as the 22nd United States Secretary of Defense from 2006 to 2011. Prior to this, Gates served for 26 years in the Central Intelligence Agency and the National Security Council, and under President George H. W....

 said that "I don't know anybody at the Department of Defense, Mr. Tiahrt, who thinks that this program should, or would, ever be operationally deployed. The reality is that you would need a laser something like 20 to 30 times more powerful than the chemical laser in the plane right now to be able to get any distance from the launch site to fire."

"So, right now the ABL would have to orbit inside the borders of Iran in order to be able to try and use its laser to shoot down that missile in the boost phase. And if you were to operationalize this you would be looking at 10 to 20 747s, at a billion and a half dollars apiece, and $100 million a year to operate. And there's nobody in uniform that I know who believes that this is a workable concept."

The Air Force has not requested any further funds for the Airborne Laser and Air Force Chief Schwartz has said that the system "does not reflect something that is operationally viable.” As of February 2011, the US has spent $5.2 billion on the project.



The heart of the system is the COIL, comprising six interconnected modules, each as large as an SUV turned on-end. Each module weighs about 6,500 pounds (3,000 kg). When fired, the laser produces enough energy in a five-second burst to power a typical American household for more than an hour.

Use against ICBMs vs TBMs

The ABL was designed for use against tactical ballistic missile
Tactical ballistic missile
A tactical ballistic missile is a ballistic missile designed for short-range battlefield use. Typically, range is less than . Tactical ballistic missiles are usually mobile to ensure survivability and quick deployment, as well as carrying a variety of warheads to target enemy facilities, assembly...

s (TBMs). These have a shorter range and fly more slowly than ICBMs. The MDA has recently suggested the ABL might be used against ICBMs during their boost phase. This could require much longer flights to get in position, and might not be possible without flying over hostile territory. Liquid-fueled ICBMs, which have thinner skins, and remain in boost phase longer than TBMs, might be easier to destroy.

If the ABL achieves its design goals, it could destroy liquid-fueled ICBMs up to 600 km away. Tougher solid-fueled ICBM destruction range would likely be limited to 300 km, too short to be useful in many scenarios, according to a 2003 report by the American Physical Society
American Physical Society
The American Physical Society is the world's second largest organization of physicists, behind the Deutsche Physikalische Gesellschaft. The Society publishes more than a dozen scientific journals, including the world renowned Physical Review and Physical Review Letters, and organizes more than 20...

 on National Missile Defense
National Missile Defense
National missile defense is a generic term for a type of missile defense intended to shield an entire country against incoming missiles, such as intercontinental ballistic missile or other ballistic missiles. Interception might be by anti-ballistic missiles or directed-energy weapons such as lasers...


Intercept sequence

The ABL system uses infrared sensors for initial missile detection. After initial detection, three low power tracking lasers calculate missile course, speed, aimpoint, and air turbulence. Air turbulence deflects and distorts the laser beam. The ABL adaptive optics
Adaptive optics
Adaptive optics is a technology used to improve the performance of optical systems by reducing the effect of wavefront distortions. It is used in astronomical telescopes and laser communication systems to remove the effects of atmospheric distortion, and in retinal imaging systems to reduce the...

 use the turbulence measurement to compensate for atmospheric errors. The main laser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...

, located in a turret on the aircraft nose, is fired for 3 to 5 seconds, causing the missile to break up in flight near the launch area. The ABL is not designed to intercept TBMs in the terminal, or descending, flight phase. Thus, the ABL must be within a few hundred kilometers of the missile launch point. All of this occurs in approximately 8 to 12 seconds.

Operational considerations

The ABL does not burn through or disintegrate its target. It heats the missile skin, weakening it, causing failure from high speed flight stress. The laser uses chemical fuel similar to rocket propellant to generate the high laser power. Current plans call for each 747 to carry enough laser fuel for about 20 shots, or perhaps as many as 40 low-power shots against fragile TBMs. The ABL aircraft must land to refuel the laser. Preliminary operational plans call for the ABL to be escorted by fighters and possibly electronic warfare
Electronic warfare
Electronic warfare refers to any action involving the use of the electromagnetic spectrum or directed energy to control the spectrum, attack an enemy, or impede enemy assaults via the spectrum. The purpose of electronic warfare is to deny the opponent the advantage of, and ensure friendly...

 aircraft. The ABL aircraft would likely orbit near potential launch sites (located in hostile countries) for long periods, flying a figure-eight pattern that allows the aircraft to keep the laser aimed toward the missiles. The aircraft can be refueled in flight, enabling it to stay aloft for long periods.

Use against other targets

In theory, the ABL could be used against hostile fighter aircraft, cruise missiles, or even low-earth-orbit satellites (see anti-satellite weapon
Anti-satellite weapon
Anti-satellite weapons are designed to incapacitate or destroy satellites for strategic military purposes. Currently, only the United States, the former Soviet Union, and the People's Republic of China are known to have developed these weapons. On September 13, 1985, the United States destroyed US...

). However, as they are not its intended target, the capability against them is unknown. The ABL infrared target acquisition system is designed to detect the hot exhaust of TBMs in boost phase. Satellites and other aircraft could have a much lower heat signature, making them more difficult to detect. An analysis by the Union of Concerned Scientists
Union of Concerned Scientists
The Union of Concerned Scientists is a nonprofit science advocacy group based in the United States. The UCS membership includes many private citizens in addition to professional scientists. James J...

 discusses potential ABL use against low earth orbit satellites.

Use against ground targets seems unlikely. Aside from the difficulty of acquiring and tracking a ground target, firing through the dense atmosphere would weaken the beam. Ground targets such as armored vehicles are not fragile enough to be damaged by a megawatt-class laser. Another program, the Advanced Tactical Laser
Advanced tactical laser
The Advanced Tactical Laser program is a US military program to mount a high energy laser weapon on an aircraft, initially the AC-130 gunship, for use against ground targets in urban or other areas where minimizing collateral damage is important. The laser will be a 100 kilowatt-class chemical...

, envisions air-to-ground use of a megawatt-class laser mounted on an aircraft better suited for low altitude flight.

See also

External links

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