FY97 DOT&E Annual Report


DoD ACAT ID Program
7 aircraft
Total program cost (TY$) $6118M
Average unit cost (TY$) $528M
Full-rate production FY05

Prime Contractor


The Airborne Laser (ABL) is intended to shoot down enemy theater ballistic missiles (TBMs) during their powered boost phase of flight During this phase, the missiles are most vulnerable to laser radiation. The ABL engagement concept calls for the laser to focus on a distant missile's booster skin, rupturing it or damaging it sufficiently to cause the missile to lose thrust or flight control and fall short of its intended target. The aircraft will be a modified Boeing 747-400F (freighter), carrying a megawatt-class Chemical Oxygen Iodine Laser (COIL), which operates in the near infrared 1.315 mm wavelength. In addition to the laser, ABL will carry a beam and fire control system and a battle management, command, control, communications, computers, and intelligence (BMC4I) system. The beam control system will use adaptive optics to offset the degrading effects of atmospheric turbulence on the laser beam's propagation. The most notable feature of the aircraft will be the turret ball on its nose, which contains the laser's primary pointing mirror.

ABL will be rapidly deployable and will add a boost-phase layer to Theater Missile Defense's (TMD) Family of Systems. It will be positioned safely behind (90 km nominally) the forward line of friendly troops and moved closer towards enemy airspace as local air superiority is attained. A five aircraft fleet will support two 24 hour combat air patrols in a theater.

Theater missile defense is a central aspect of Joint Vision 2010. ABL will exploit technological innovation to achieve precision engagement. Operationally it will provide for full-dimensional protection of U.S. and friendly forces, including cites, ports, airfields, and other infrastructures in the theater.


The technologies supporting ABL have evolved from over 25 years of DoD and the Air Force Research Laboratory's (AFRL at Kirtland AFB, NM) work in the areas of laser power generation, pointing and tracking, and adaptive optics. In the early 1980s, the laboratory operated the Airborne Laser Laboratory, which successfully shot down five AIM-9 air-to-air missiles and a simulated cruise missile BQM-34. During the 1980s as well, the Strategic Defense Initiative Organization (now the Ballistic Missile Defense Organization) funded a great deal of work in adaptive optics and beam control. The net result of these technology investments was the feasibility of an airborne laser capable of shooting down distant TBMs. The Air Force launched a formal program in FY94, awarding two separate concept design contracts to competing teams. The program passed through Milestone I (MS I) into the Program Definition and Risk Reduction (PDRR) phase in November 1996, as it selected the winning team: Boeing (prime), TRW (laser) and Lockheed Martin (beam control).

The next major review of the ABL program will occur at Authority-to-Proceed (ATP)-1 in June 1998. The decision will validate placement of the order for the, PDRR aircraft in January 1998. The ATP-1 decision will be based on (1) demonstration of a light weight laser module; (2) demonstration of active tracking; (3) atmospheric turbulence characterization; and (4) demonstration of combined compensation and fine tracking. The PDRR ABL will have half the laser power of the EMD and operational system, but will not have a fully capable BMC4I system.

An ATP-2 review is scheduled for late FY01. ATP-2 criteria include demonstrating performance of the integrated PDRR beam control system at low power, laser scaling and multi-module operation of the PDRR laser modules, and an integrated surveillance system performance. This review will authorize the long-lead purchase of the Engineering, Manufacturing and Development (EMD) aircraft and flight tests of the PDRR ABL, which culminate in a lethal intercept demo against a boosting TBM in late FY02. Milestone II for the program is in FY03. After the EMD ABL is delivered, it will be used for IOT&E in FY05. Milestone III is scheduled for the second half of FY05.


Testing will be managed and conducted in accordance with the ABL TEMP. The current version of the TEMP was approved in April 1996 and developed to support the PDRR phase. The TEMP will evolve as the ABL system becomes better defined. At present, ABL test activity concerns the collection of the engineering data needed to assess potential system performance in support of the ATP-1 and ATP-2 decisions. Work has been done on adaptive optics at the AFRL Starfire Optical Range since 1980. AFRL has tested the improved chemical efficiency of COILs. AFRL also led the Airborne Laser Experiment (ABLE-X) and Airborne Laser Extended Atmospheric Characterization Experiment (ABLE-ACE) airborne data collection and experimentation programs concerned with adaptive optics performance. Sponsored by the ABL System Program Office (SPO), AFRL is presently collecting high altitude atmospheric optical turbulence data in all four seasons in Korea and the Middle East. The turbulence data is collected using aerothermal probes on balloons and aircraft to measure the vertical and horizontal turbulence profiles respectively. AFRL conducted an active tracking demonstration at White Sands Missile Range in FY96. In addition, demonstrations of combined active tracking and atmospheric compensation were conducted at MIT Lincoln Laboratory's Firepond facility on a range scaled to represent ABL engagement conditions. The degree to which these demonstrations satisfy some specific ATP-1 exit criteria is currently under review.

The program will continue work in the area of lethality to characterize kill mechanisms against various types of threat missiles and to assess the effects of countermeasures. Test activity in FY01 will center on the System Integration Laboratory (SIL). The SIL will be built at the Birk Flight Test Facility at Edwards AFB, CA. The SIL will be a form, fit, and function replica using the actual PDRR ABL optical and laser systems. A range simulator will capture the high and low power laser beams during ground testing. This will allow the collection of laser beam profile and power diagnostics.


DOT&E has several concerns about significant technical challenges to ABL's ability to perform effectively. The effects of atmospheric turbulence and countermeasures may force the ABL platform to move closer to enemy anti-air defenses to maintain effectiveness. The platform integration requirements in order to maintain stability of the optics and lasing subsystems will also be challenges to ABL's ability to deliver energy on target. These and other issues will continue to be tracked by DOT&E during program analysis, testing and evaluation.

A hypothetical omnibus critical operational issue for ABL might best be stated as follows: "Can ABL meet its Single-Shot Probability of Kill and weapon range requirements in operationally representative scenarios using laser dwell times that support an antisalvo capability and conserve laser fuels?" An important point related to this issue is that the ABL Operational Requirements Document does not presently require ABL to have an antisalvo capability, whereas the ABL Technical Requirements Document does. The salvo requirement will need to be addressed in future program milestones.

In addition to characterizing ABL's stand-alone combat potential when it is up and running, ABL testing will strive to measure the interoperability of ABL with other TMD assets and the overall reliability, maintainability, and availability of the system.

Lethality is and will remain a central ABL issue. Threat missile construction and operation, including potential or known countermeasures, must be reasonably well known, analyzed an understood in order to support a rigorous assessment of how much power ABL must put on targets in order to kill or disable them.

DOT&E considers ABL a high-risk, $6.2B program that is revolutionary in nature. While OT is not planned for several years, DOT&E will continually assess and analyze several technical challenges that have significant impact on the operational effectiveness and suitability of an ABL system. Some of those areas are (1) the widely discussed effect of atmospheric turbulence and the ability of adaptive optics to counteract that effect, (2) the integration of highly sensitive optical instruments into a dynamic air platform, (3) airframe generated atmospheric perturbations, (4) software integration and testing to support battle management, and (5) the potential to achieve expected kill mechanisms against various threat designs, countermeasures, and missile dynamics.


The ABL program has yet to mature to the point where this item applies. However, the program has basically been well run. The SPO supported the MS-I decision with good documentation and has been responsive to OSD and other investigation and criticism.