DOT&E Director, Operational Test & Evaluation  
FY98 Annual Report
FY98 Annual Report

AIRBORNE LASER (ABL)


Army ACAT IC Program: Prime Contractor
Total Number of Systems:7 aircraftBoeing
Total Program Cost (TY$):$6118M 
Average Unit Cost (TY$):$528MService Certified Y2K Compliant
Full-rate production:FY05Yes - 30 April 1998

SYSTEM DESCRIPTION & CONTRIBUTION TO JOINT VISION 2010

The Airborne Laser (ABL) is intended to shoot down enemy theater ballistic missiles (TBMs) during their powered boost phase of flight. It is during this phase that TBMs 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 cause a loss of 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 microns). 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 the 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 utilize technological innovation to achieve precision engagement. Operationally, it will provide for full-dimensional protection of U.S. and friendly forces, and cities, ports, airfields, and other infrastructure in the theater.


BACKGROUND INFORMATION

The technologies supporting ABL have evolved from more than 25 years of DoD and Air Force Research Laboratory (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. In addition, the Strategic Defense Initiative Organization (now the Ballistic Missile Defense Organization) funded a number of efforts relating to 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. In FY94, the Air Force launched a formal program, which awarded two separate concept design contracts to competing teams. The program passed Milestone I and entered the Program Definition and Risk Reduction (PDRR) phase in November 1996. The Air Force selected a single team from the two competing concept teams by awarding the activity to the team of Boeing (prime), TRW (laser), and Lockheed Martin (beam control).

ABL successfully passed the first Authority to Proceed (ATP-1) decision in June 1998. This decision allowed the Air Force to commit to the purchase of a commercial 747-400, which is the airborne platform for the PDRR system. The ATP-1 decision was based on: (1) demonstration of a lightweight laser module; (2) demonstration of active tracking; (3) characterization of atmospheric turbulence; and (4) demonstration of compensation and fine tracking.

An ATP-2 review is scheduled for late FY01. ATP-2 criteria include: (1) demonstrating performance of the integrated PDRR beam control system at low power; (2) laser scaling and multi-module operation of the PDRR laser modules; and (3) an integrated surveillance system performance. This review will authorize the long-lead purchase of the EMD aircraft and flight tests of the PDRR ABL. The PDRR-designed ABL will attain about half of the laser power planned for the operational system and fully demonstrate the capability of the on-board BM/C4I system. The PDRR ABL will undergo extensive testing to validate projected performance, and will culminate with a lethal intercept demonstration against a boosting TBM in late FY02. Milestone II for the ABL program is scheduled for FY03. After the EMD ABL is delivered, it will be used for IOT&E in FY05. Milestone III is scheduled for 2QFY05.


TEST & EVALUATION ACTIVITY

An ABL TEMP was approved in April 1996 in support of the Milestone I decision reached later that year. Work has begun in the System Program Office to add increased definition to the test program, and to generate a new TEMP reflective of the progress made within the last two years.

ABL test activity has focused on collecting atmospheric turbulence data. Early efforts include the Airborne Laser Experiment and the Airborne Laser Extended Atmospheric Characterization Experiment. These experiments were supplemented by a series of experiments that took place in 1997 and 1998, to collect data throughout the year in Korea and Southwest Asia using balloons and aircraft flights. These campaigns yielded significant data that are now being analyzed to gain a better understanding of operational turbulence levels and how they affect ABL performance.

In FY96, tracking and compensation demonstrations in support of ATP-1 were conducted at White Sands Missile Range and at MIT Lincoln Laboratory's Firepond facility.

Another area of ongoing test activity pertains to lethality mechanisms. Several experiments have been conducted by AFRL to measure fundamental thermodynamic and optical properties of relevant materials, including some countermeasure candidates. These measurements include high-temperature properties and the response of their materials. To gain a better understanding of the internal operating condition of an in-flight missile, critical components and subsystems have been investigated under simulated flight and/or propulsive conditions at AFRL-sponsored tests.

Much of the work described here will continue in FY99. In addition to this data, important test information will come from other sources. During PDRR, the System Integration Laboratory (SIL), which will be built at the Birk Flight Test Facility at Edwards AFB, will be an important resource. The SIL will house the actual PDRR ABL into a hanger, and characterize certain aspects of system performance, such as the beam profile and turret operation. The Virtual ABL at Boeing will be used to integrate and checkout system software. There are also plans to conduct additional tests during EMD at the Theater Air Combat and Control Simulation Facility at Kirtland AFB.


TEST & EVALUATION ASSESSMENT

DOT&E has several concerns about ABL's effectiveness. The effects of atmospheric turbulence and countermeasures may force the ABL platform to move closer to enemy anti-air defenses in order to maintain effectiveness. In addition, the interoperability aspects of ABL testing, including cross-cueing and damage assessment of successful intercepts and support of other TMD systems need to be fully explored through simulation and demonstration. These and other issues will continue to be tracked by DOT&E during the PDRR phase. DOT&E has noted specific technical challenges faced by the ABL, including the:

In light of these challenges, DOT&E has several concerns regarding the adequacy of the test program planned for ABL. A primary concern is that the EMD phase is very short (18 months), and only six months have been planned for IOT&E during EMD. Unless tremendous maturity can be demonstrated during PDRR, this compressed schedule adds unnecessary risk to the EMD phase. The high-risk of the ABL program is driven by: (1) a minimum margin, success oriented, development schedule; and (2) underestimating the amount of testing required to verify integration and operation of sub-systems (laser generation, target detection, beam control, BM/C4I) onto the aircraft, as well as the operational utility of the aircraft. Although EMD is still several years away, more definitive test planning for DT&E and IOT&E should begin now.

In general, the $25 million FY99 congressional cut may slip most ABL milestones approximately one year. The Air Force has properly focused its priorities on the PDRR aircraft and risk reduction activities. Current ABL acquisition strategy remains essentially unchanged; it simply takes place over a longer period of time. The risk reduction efforts added by the Air Force after ATP-1 will include additional activities identified to address the findings of the Welch Report on missile defense systems. These activities will serve to demonstrate key ABL operational capabilities, at the component level, as soon as possible.

The top-level ABL operational issue is whether it can meet its Single-Shot Probability of Kill and weapon range requirements in operationally representative scenarios using laser dwell times that support multiple, near simultaneous launches and conserve laser fuels? An important point related to this issue is that the ABL Operational Requirements Document does not currently require ABL to have the capability to handle multiple, near simultaneous TBM launches, although the ABL Technical Requirements Document does. This requirement will need to be addressed at future program milestones.

ABL is a revolutionary military system with a strong potential for missile defense, as well as a high potential for developmental risk. DOT&E is working with the ABL program office to ensure that critical data concerning ABL's projected performance is available at planned program decision points. DOT&E plans to continually assess and analyze the technical challenges posing the most impact on the operational effectiveness and suitability of the ABL to ensure that developmental risk is minimized. As previously discussed, these areas include the: (1) effects of atmospheric turbulence and the ability of adaptive optics to counteract that effect; (2) integration of highly sensitive optical instruments into a dynamically vibrating air platform; (3) effects of airframe generated atmospheric perturbations on laser propagation; (4) software development, integration and testing of the critical ABL BM/C4I system; and (5) validation of ABL's potential to achieve expected kill mechanisms against the full spectrum of threats, launch scenarios, countermeasures, and missile dynamics.


Return to Table of Contents