What’s Next for Airborne Laser?

April 1, 2010

On the night of Feb. 11, off the coast of Southern California, the Missile Defense Agency scored a major achievement by destroying a liquid-fueled ballistic missile target in flight. The important part was that it did so using a laser weapon carried onboard a Boeing 747-400 aircraft.

This milestone event constituted the first publicly announced test success for the Airborne Laser (ABL). However, the success was actually the second of its kind within an eight-day period. On Feb. 3, the ABL aircraft was used to destroy a solid-fueled missile during its boost phase. This test was not announced until ABL was successfully used against the liquid-fueled (Scud-type) target a little more than a week later.

The Boeing-led ABL team won the contract for the multibillion-dollar program nearly 14 years ago. February’s test success was the key event toward which the program had been building for years.

However, the successes probably came years too late for a program that was once a top missile defense priority. When the Obama Administration handed Congress its defense budget for Fiscal 2011, Pentagon officials announced that the Airborne Laser would be shifted out of MDA, which has managed the program since 2002. ABL will be given to the director of defense research and engineering for use as a directed energy test bed.

The Airborne Laser prototype platform, a modified Boeing 747, on the flight line. (MDA photo)

That move appears to be the final signal that ABL will never see operational use.

MDA officials are now pondering the future of what is now termed the Airborne Laser Test Bed (ALTB). “Subsequent experiments are in the planning stages pending data analysis from last week’s experiment,” said an MDA spokesman. “There is only a notional schedule with notional objectives at this time.”

The prototype platform used in the two February tests is a modified 747 cargo aircraft that measures approximately 231 feet long with a wingspan of 211 feet. The megawatt-class chemical oxygen iodine laser that gives the ABL its knockout punch comprises six modules carried in the rear of the aircraft. Each module is the size of a large sport utility vehicle.

The aircraft uses six infrared sensors to spot the exhaust from a boosting missile. Once the missile is detected, a lower power, kilowatt-class solid-state laser called the Track Illuminator tracks it and determines an aim point.

A second kilowatt-class solid-state laser, the Beacon Illuminator, measures atmospheric disturbances. These disturbances are corrected by an adaptive optics system onboard the aircraft allowing the high-energy laser to accurately point and focus on the target.

As seen in the Feb. 11 test, the high-energy laser is fired through a turret (protruding from the front of the aircraft) at the target missile, “heating the boosting ballistic missile to critical structural failure,” MDA said in an announcement. “The entire engagement occurred within two minutes of the target missile launch, while its rocket motors were still thrusting.”

Boost Phase Success

Destroying missiles during their boost phase is important because it means debris and wreckage will fall back down onto enemy territory, not around the intended target.

Less than an hour after the successful shot in February, the ABL Test Bed targeted a second solid-fueled missile. This time, however, although the target was engaged by the high-energy laser, the test was terminated before the missile actually was destroyed.

Rep. Trent Franks, an Arizona Republican who co-chairs the House Missile Defense Caucus, said he asked the Missile Defense Agency for a briefing on the two successful ABL tests. “That is already in the works,” he said in February. “The challenge is whether it can be an open briefing or closed.”

In 1996, the Air Force awarded the ABL contractor team a $1.1 billion contract to build a prototype aircraft and attempt a target missile shootdown within five years. The idea of a laser weapon appealed greatly to missile defense supporters who argued that targeting a missile in what is known as the boost phase, as the missile is lifting off and gaining altitude, would be the best way to defeat the threat. The boost phase lasts for approximately 300 seconds—hence the attraction of a speed-of-light weapon.

That five-year goal came and went as the program was plagued with technical issues and rising costs. The Air Force’s original plan for operating the ABL called for seven aircraft dispersed to two combat theaters, three in each location with one additional aircraft that could be used if any aircraft were down for maintenance. The service estimated each ABL would cost between $1 billion and $1.5 billion, and that it would take at least two years to roll one off a production line.

A high-energy laser flows through, and is directed by, the ABL’s nose turret. (MDA photo)

Critics seized on the cost of the aircraft—ABL would have been the second most expensive production aircraft behind the B-2 bomber—and a questionable operating concept. Because the ABL would be a slow moving, very large target, USAF planned to have fighter aircraft escort it on missile defense sorties, adding to the operating cost. The Missile Defense Agency in a 2006 report to Congress revealed an operating concept that required “at least three aircraft for a near-continuous single combat air patrol station.”

Additional aircraft “may be required depending on the length of deployment, capabilities of the aircraft available, and whether or not the combatant commander needs near-continuous or continuous coverage,” MDA added. “The specific quantity of operational assets required for deployment periods of seven days, 30 days, 90 days, and one year” had not been determined.

The aircraft would also be limited in where they could be used.

The ideal scenario seemed to be that of military action against North Korea. ABL could fly off the coast, away from air defenses, and theoretically target North Korean ballistic missiles as they lifted off the launchpad.

Along with the cost of building each aircraft, ABL requires a large logistics tail. The 2006 MDA report to Congress laid out some requirements for the aircraft to be used operationally. “Normal large-aircraft servicing such as heavy-load ramps and taxiways, 8,000-plus-foot runways, de-icing, aircraft fueling, maintenance stands, and cargo handling equipment are necessary, but may be available for use at an in-theater forward operating area.

“Consideration must be given to space requirements for laser fueling area and laser fuel mixing/storage facilities that would be required to maintain the Airborne Laser refueling requirements.”

The report noted that “properly maintained” fuel could last up to two weeks if not used in a sortie. “The Airborne Laser could maintain an orbit, preventing enemy launches for this duration without resupply as long as no hostilities occur. Once hostilities start, refueling will be necessary.”

In August 2001, Air Force officials upped the program’s cost estimate by 50 percent and delayed the schedule by four years. That November, the Defense Department transferred management of the ABL program to the Ballistic Missile Defense Organization, MDA’s predecessor.

Costs rose each succeeding year. According to MDA, the prototype aircraft used for the tests earlier this year carries a $5 billion-plus price tag.

In 2006, the Bush Administration, struggling with ABL, announced it was relegating the program to “technology demonstrator” status. The Air Force’s ABL procurement plans were put on hold at that time.

Despite what appears to be a real uphill battle, ABL supporters in Congress plan to keep fighting to keep it alive. Franks will try to change the Obama Administration’s plans as Congress considers the Fiscal 2011 defense budget.

“I am going to do everything I can to rally other members of Congress to recognize the amazing achievement that has occurred here with this lethal shootdown,” Franks said, adding that he would offer amendments to the defense authorization and appropriations bills.

However, Franks acknowledges that missile defense supporters face big obstacles.

The ABL, shown here in flight, could carry fuel that would last two weeks. (Boeing photo)

“It’s been so discouraging working with members of Congress that either don’t have any understanding of the efficacy of this program or have an intrinsic bias against anything to do with missile defense, and this is especially true of the President of the United States,” he said. “The good news” is that the successful tests make it “impossible for them with a straight face to suggest that the system can’t work.”

Franks said he believes the successful tests will “give people like me leverage to go to other members of Congress and help them understand the profound capability of this system and what it represents in our chain of technology for the future. I think lasers will ultimately be to missile defense what the silicon chip was to the computer industry.”

In March 2009, Franks and six other House members wrote to Defense Secretary Robert M. Gates to express their worry that the ABL would see its funding cut in the Fiscal 2010 budget. One of the letter signers was Rep. Norman D. Dicks (D-Wash.), who became chairman of the House Appropriations defense subcommittee following the death of Rep. John P. Murtha (D-Pa.) in February.

Franks said he expects ABL supporters to once again send Gates a letter and ask that the program be reconsidered in light of the two recent tests, but Gates has previously taken a particularly hard line on the program.

Stinging Criticism

When he appeared before the House Appropriations defense subcommittee last year, Gates pulled no punches in his assessment of ABL. “I don’t know anybody at the Department of Defense, Mr. Tiahrt, who thinks that this program should, or would, ever be operationally deployed,” Gates said in answer to a question posed by Rep. Todd Tiahrt (R-Kan.). “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.”

Gates continued his stinging criticism of the program. “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,” he told Tiahrt. “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.”

There is “nobody in uniform that I know who believes that this is a workable concept,” Gates added. “I have kept the first—the prototype—because we do need to continue the research on directed energy and on lasers, and that will be robustly funded because we do need to continue developing a boost-phase capability, but, operationally, this first test, for example, is going to be from a range of 85 miles.”

A view from the ABL Test Bed aircraft shows the laser beam’s path and a piece of missile debris knocked loose by the heat. (MDA photo)

The two recent tests don’t seem to have changed Gates’ mind any. During a Feb. 18 Pentagon press briefing, Gates’ spokesman Geoffrey S. Morrell said the Secretary has never been against the idea of a laser weapon for missile defense. “He had issues with the platform. The [concept of operation] on the platform didn’t work,” Morrell said.

Asked if ABL carried out the February tests using what would be considered operating power, a Missile Defense Agency spokesman said, “ALTB generated the power necessary to destroy the target missile,” adding that the ALTB is a test bed platform only, and not intended for missile defense operations.

DOD spokesman Morrell added that the Obama Administration still believes directed energy systems hold the most promise for boost phase missile defense, and that the Administration was continuing to fund research in that area.

Franks is also not putting full stock in Gates’ public comments about ABL. “I hope and believe that [Gates] will have the core commitment to the defense capability of this nation that he will use his highly influential voice to either make sure this program goes forward or to have an equal or better platform. This is the best platform we have.”

Even in a time when money for weapon systems is becoming very difficult to come by, Franks sees intense value in ABL. “If this thing shoots down one nuclear missile coming into the United States, it will pay for itself 100 times over and more,” he said.

Missile defense supporters feel the decisions being made today about ABL will have long-lasting repercussions. “I’ve got year-and-half-old twins and I want to make sure that they and their contemporaries walk in the sunlight of freedom,” Franks said.

Laser Missile Defense’s Long Road

The Airborne Laser program faces uncertainty, and the technology has already endured a lengthy development program with many starts and stops over several decades.

ABL can actually trace its existence to a 1917 treatise published by Albert Einstein. The famous physicist’s paper laid out the principles for producing a “stimulated” emission of light, according to an official history of the program.

The Eisenhower Administration first began looking at using lasers on the battlefield. Interest accelerated following the 1962 Cuban Missile Crisis when President Kennedy specifically requested research on using lasers to shoot down ballistic missiles in flight.

Through the 1960s, 1970s, and early 1980s, the Air Force invested in research to carry a laser aboard an aircraft and use it to shoot down targets. The service achieved that goal in 1983 when the Airborne Laser Laboratory, a KC-135A fitted with a 100 kilowatt CO2 laser, shot down an AIM-9B Sidewinder missile.

The service followed that up with two more successful tests.

The Airborne Laser Laboratory was considered an experimental aircraft and was retired by the Air Force in 1984. About a decade later, however, the Clinton Administration revived the idea of a flying laser weapon that could shoot down ballistic missiles.

The experience of Saddam Hussein’s Scud attacks on American troops during the first Gulf War played a part in the decision to move ahead with the plan for an Airborne Laser.

Thomas Duffy is publisher of Inside Washington Publishers’ Defense Group, which includes the InsideDefense.com online news service. This is his first article for Air Force Magazine.