Defense Acquisitions: DOD Efforts to Develop Laser Weapons for Theater Defense
Published: 1999-03-31T00:00:00

Fast Facts:

Highlights:
section_title: Why GAO Did This Study
paragraphs: Pursuant to a congressional request, GAO reviewed the Department of Defense's (DOD) programs to develop laser weapons for missile defense, focusing on: (1) what laser weapons are being considered for missile defense and the coordination among the program offices developing the systems; (2) the status and cost of each system; and (3) the technical challenges each system faces as determined by DOD program managers and analysts and other laser system experts.
section_title: What GAO Found
paragraphs: GAO noted that: (1) DOD is developing two laser weapons--the Airborne Laser (ABL) and the Space-Based Laser (SBL)--which U.S. forces intend to use to destroy enemy ballistic missiles; (2) in a joint effort with Israel, DOD is developing a ground-based laser weapon, the Tactical High Energy Laser (THEL), which Israel will use to defend its northern cities against short-range rockets; (3) ABL is funded and managed by the Air Force, SBL is jointly funded by the Ballistic Missile Defense Organization and the Air Force, and THEL is funded jointly with Israel and managed by the Army; (4) ABL, SBL, and THEL are in varying stages of development ranging from conceptual design studies to integration and testing of system components; (5) the ABL program is in the program definition and risk reduction acquisition phase and is scheduled for full operational capability in 2009, with a total of seven ABLs; (6) this schedule reflects a 1-year delay from the original schedule; (7) the Air Force estimates the life-cycle cost of the ABL to be about $11 billion; (8) the SBL program is about a year into a $30-million study phase to define concepts for the design, development, and deployment of a proof of concept demonstrator; (9) DOD estimates that it will cost about $3 billion to develop and deploy the demonstrator; (10) the future of the SBL program is unknown, pending the outcome of a DOD assessment of the program; (11) the $131.5-million THEL Advanced Concept Technology Demonstration program is about 34 months into a 38-month program; (12) system components have been built, but system testing has been delayed from December 1998 to July 1999 due to administrative and technical problems; (13) laser experts agree that the ABL, SBL, and THEL face significant technical challenges; (14) the technical complexity of the ABL program has caused laser experts to conclude that the ABL planned flight test schedule is compressed and too dependent on the assumption that tests will be successful and therefore does not allow enough time and resources to deal with potential test failures and to prove the ABL concept; (15) if DOD ultimately decides to continue the SBL program, the size and weight limitations dictated by current and future launch capabilities will force the program to push the state of the art in laser efficiency, laser power, and deployable optics; and (16) initial testing of THEL's laser has identified problems with the operation of chemical flow control valves and with the low-power laser that is to be used in tracking short-range rockets the system is being designed to defeat.

section_title: Letter
paragraphs: This report responds to your request that we conduct a review of Department of Defense  (DOD) programs to develop laser weapons for missile defense.  Specifically, you asked us to  (1) identify what laser weapons are being considered for missile defense and the coordination  among the program offices developing the systems, (2) determine the current status and cost  of each system, and (3) identify the technical challenges each system faces as determined by  DOD program managers and analysts and other laser system experts.  The report recommends  that the Secretary of Defense direct the Secretary of the Air Force to reconsider plans to  exercise the option for the second ABL aircraft for the engineering and manufacturing  development phase of the Airborne Laser program before flight testing of the Airborne Laser  system developed during the program definition and risk reduction phase has demonstrated  that the Airborne Laser concept is an achievable, effective combat system.
We are sending copies of this report to Senator Pete V. Domenici, Senator Daniel K. Inouye,   Senator Carl Levin, ’’Senator Frank R. Lautenberg, Senator Joseph I. Lieberman, Senator Rick  Santorum, Senator Ted Stevens, Senator John W. Warner, Representative Duncan L. Hunter,  Representative John R. Kasich, Representative Jerry Lewis, Representative John P. Murtha,  Representative David R. Obey, Representative Norman Sisisky, Representative Ike Skelton,   Representative Floyd D. Spence, Representative Curt Weldon, and Representative C.W. Bill  Young in their capacities as Chair or Ranking Minority Member of Senate and House  Committees and Subcommittees.  We are also sending copies of this report to the Honorable  William Cohen, Secretary of Defense; the Honorable F. Whitten Peters, Acting Secretary of the  Air Force; the Honorable Louis Caldera, Secretary of the Army; the Honorable Jacob Lew,  Director, Office of Management and Budget; and Lieutenant General Lester L. Lyles, Director,  Ballistic Missile Defense Organization.  Copies will also be made available to others on request.
Please contact me at (202) 512-4841 if you or your staff have any questions  concerning this report.  Major contributors to this report are listed in  appendix II.
subsections: section_title: Introduction
paragraphs: The Department of Defense (DOD) and Congress have become increasingly  concerned that U.S. and allied troops abroad may be attacked by chemical,  biological, or nuclear weapons delivered by ballistic missiles.  Operation  Desert Storm demonstrated that the U.S. military and other allied forces  have limited capability against theater ballistic missiles.  In fact, U.S.  defensive capability is limited to weapons that defend against missiles  nearing the end of their flight, such as the Patriot.  Consequently,  developing weapon systems to defeat these threats is DOD’s top priority in  its overall ballistic missile defense program.
DOD has been working with laser technology for a long time.  The  following table shows some of the laser development efforts that DOD has  undertaken.  To date, none of these efforts has resulted in an operational  laser weapon system.
Currently, DOD is developing a variety of weapon systems as part of its  Theater Missile Defense program to counter the potential threats posed by  ballistic missiles.  The first generation of these weapon systems uses  interceptor missiles to intercept and destroy enemy missiles in the latter  stages of the missiles' flight.  Included among these systems are the Patriot  Advanced Capability-3, an improved version of the Patriot system that was  used during the Gulf War; Navy Area Defense; Medium Extended Air  Defense System; Theater High Altitude Air Defense; and Navy Theater  Wide.
In addition, DOD is developing ballistic missile defense systems that will  use laser beams to destroy enemy missiles.  DOD plans to spend billions of  dollars to develop these laser weapons and place them in the air (Airborne  Laser) and in space (Space-Based Laser). In addition, DOD is developing a  ground-based laser (Tactical High-Energy Laser) that is to be used to  destroy short-range artillery rockets.
Congress has generally endorsed DOD’s efforts to develop and produce  these laser weapon systems.  Its desire to have these systems developed,  produced, and deployed as soon as possible was heightened by a July 1998  report by the Commission to Assess the Ballistic Missile Threat to the  United States.  The Commission concluded, among other things, that  concerted efforts by a number of overtly or potentially hostile nations to  acquire ballistic missiles with biological or nuclear warheads pose a  growing threat to the United States, its deployed forces, and its friends and  allies.
While endorsing, and in some instances suggesting that DOD’s efforts to  develop laser weapon systems to defeat ballistic missiles be accelerated,  Congress has also expressed concern over the cost and risk associated  with developing and demonstrating the maturity of the technologies  required to develop such missile defense capabilities.
subsections: section_title: Objectives, Scope, and Methodology
paragraphs: The Ranking Minority Member, Committee on the Budget, and the Ranking  Minority Member, Subcommittee on Military Research and Development,  Committee on Armed Services, House of Representatives, asked us to  review DOD's programs to develop laser weapons for missile defense to identify what laser weapons are being considered for missile defense  and the coordination among the program offices developing the  systems, determine the current status and cost of each system, and identify the technical challenges each system faces as determined by  DOD program managers and analysts and other laser system experts.
To identify the laser weapons being considered for missile defense and  what coordination exists among the programs developing the systems, we  reviewed DOD budget and Airborne Laser (ABL), Space-Based Laser (SBL),  and Tactical High-Energy Laser (THEL) program office documents.  We  also met with officials of the Office of the Secretary of Defense; the  Ballistic Missile Defense Organization, the ABL program office; the Air  Force Space and Missile Systems Center; and the Army Space and Missile  Defense Command.
To determine the current status and cost of each system, we reviewed and  analyzed DOD; Air Force; Army; ABL, SBL, and THEL program offices; and  contractor documents regarding the status and cost of the DOD laser  weapon programs.  We discussed the laser programs with officials of the  Ballistic Missile Defense Organization; the ABL program office; the Air  Force Space and Missile Systems Center; the Army Space and Missile  Defense Command; TRW, Inc.; and Lockheed Martin Corporation.
To determine the technical challenges each system faces, we reviewed and  analyzed documents and studies from DOD; Air Force; Army; ABL, SBL,  and THEL program offices; and contractors.  We discussed the technical  aspects of the laser programs with officials of the Office of the Secretary of  Defense (Operational Test and Evaluation); the Ballistic Missile Defense  Organization; the Air Force Air Combat Command; the Air Force  Operational Test and Evaluation Center; the ABL program office; the Air  Force Scientific Advisory Board; the Air Force Space and Missile Systems  Center; the Army Space and Missile Defense Command; TRW, Inc.;  Lockheed Martin Corporation; and Lawrence Livermore National  Laboratory.
We conducted our review from November 1997 to December 1998 in  accordance with generally accepted government auditing standards.
section_title: DOD Developing Three Laser Weapons and Coordinating Its Development Efforts in Various Ways
paragraphs: DOD is developing two laser weapons, ABL and SBL, that are to be used by  U.S. forces to destroy enemy ballistic missiles.  Additionally, in a joint effort  with Israel, DOD is developing the THEL, which is to be used by Israel to  defend against short-range rockets.
All three programs have benefited from work performed by the Air Force  Research Laboratory on lasers and associated systems.  In addition, the  program directors for these three programs are coordinating their efforts  by meeting periodically to discuss and share information on technology  and program development issues.  Moreover, some of the same contractors  and contractor personnel are involved in all three programs, thereby  increasing program coordination.
subsections: section_title: Developing Three Defensive Laser Weapons
paragraphs: The ABL is to be carried by a 747 aircraft, and the SBL by a constellation of  satellites.  Both of these weapons are to be used by U.S. forces to destroy  ballistic missiles while the missiles are still in the early stage of their flight  (boost phase).  The THEL is a ground-based laser weapon Israel is to use to  defend its northern border cities against Russian-made Katyusha rocket  attacks in the final stages of the rockets' flight.
subsections: section_title: ABL Program
paragraphs: The ABL, funded and managed by the Air Force, is planned to be the first  system with the ability to detect and destroy enemy missiles in their boost  phase several hundred kilometers away.  It is a complex laser weapon  system that is being designed to detect an enemy missile shortly after its  launch, track the missile’s path, and hold a concentrated laser beam on the  missile until the beam’s heat causes the pressurized missile casing to crack,  in turn causing the missile to explode and the warhead to fall to earth well  short of its intended target.  The program involves placing a multimegawatt  laser, beam control system, and related equipment in a Boeing 747-400  freighter aircraft.  One prototype ABL is to be produced and tested in 2003  in attempts to shoot down missiles in their boost phase.  If this  demonstration is successful, the program is scheduled to move into the  engineering and manufacturing development phase in 2004.  Figure 2.1  shows the ABL concept.
The ABL is expected to operate from a central base in the United States and  be available to be deployed worldwide.  Ultimately, with a seven-aircraft  fleet, five aircraft are expected to be available for operational duty at any  given time.  The other two aircraft are expected to be undergoing  modifications or undergoing maintenance or repair.  When the ABLs are  deployed, two aircraft are to fly in figure-eight patterns above the clouds at  about 40,000 feet.  Through in-flight refueling and rotation of aircraft, two  ABLs will always be on patrol, thus ensuring 24-hour coverage of potential  missile launch sites within the theater of operations.  Each ABL is to be  capable of destroying about 20 missiles before chemicals needed to  generate the laser beam need to be replenished.  At that point, the aircraft  will have to land to refuel the laser.
section_title: SBL Program
paragraphs: The SBL, jointly funded by the Ballistic Missile Defense Organization  (BMDO) and the Air Force and managed by the Air Force, is to be capable  of detecting a missile in its boost phase, tracking the missile’s path, and  holding a concentrated laser beam on the missile until the beam’s heat  causes the missile to be destroyed.  The SBL program involves integrating a  multimegawatt laser, beam control system, and related equipment on a  space platform and launching it into low earth orbit.  Air Force estimates  show that a full SBL system would not be deployed until after 2020.   Figure 2.2 shows a notional SBL engagement.
DOD is developing the SBL to provide a continuous global boost phase  intercept capability for both theater and national missile defense.  The  notional concept involves having a constellation of 20 to 35 SBLs.  Each  SBL is to be capable of destroying about 100 missiles and is to have a range  of about 4,300 kilometers.
section_title: THEL Program
paragraphs: The THEL, funded jointly with Israel and managed by the U.S. Army, is a  ground-based laser weapon that is to be used to destroy short-range  rockets toward the end of their flights.  THEL is to accomplish this by  detecting an incoming rocket shortly after it has been launched, tracking  the rocket's path, and holding a concentrated laser beam on the rocket's  warhead until the beam's heat causes the warhead to detonate, destroying  the rocket.  The THEL program involves designing and building a  multi-hundred kilowatt chemical laser, a beam control system, a fuel supply  system, a laser exhaust system, and other equipment to fit into separate,  transportable containers, sized so that each container can be transported  by a large truck.  The transportable containers are to be placed on concrete  pads at deployment sites.  Once deployed, the THEL components in each  separate container are to be integrated.  All THEL components have been  produced and are scheduled to be integrated and tested at White Sands  Missile Range, New Mexico, in July 1999.  Figure 2.3 shows the THEL  concept.
DOD is developing the THEL, in a joint effort with Israel, to be used by  Israel to defend against Russian-made Katyusha rockets and other short- range rockets that have been used by terrorists to attack cities in northern  Israel.  The number of rockets THEL is capable of destroying is limited only  by the amount of laser fuel stored at the deployment site.
Although THEL is a transportable system that can be moved by large  trucks, it is not a mobile system, in the sense that the integrated system  cannot move under its own power.  Because of this limitation, the United  States has no use for THEL as it is currently designed.  See chapter 5 for  additional discussion of the U.S. need for a mobile THEL-type system.
section_title: Coordination and Technology Sharing
paragraphs: The three laser weapon development programs have coordinated their  efforts by holding periodic program director conferences to share  information.  In addition, some of the same contractors and contractor  personnel are involved in all three programs and all three programs have  benefited from work performed by the Air Force Research Laboratory on  lasers and associated systems.
According to the program directors of the ABL, SBL, and THEL, they have  conducted periodic conferences and frequent phone conversations to  discuss and share information on technology and program development  issues.  They told us that technology developed under one program is  shared where appropriate by all programs, thereby reducing duplication.   For example, weight reduction techniques developed under the SBL  program are to be used on the ABL and THEL programs.
TRW is a subcontractor for the ABL and SBL programs and the prime  contractor for the THEL program and is developing the lasers for all three  programs.  ABL program officials told us that some of the same TRW  personnel work on all three programs, thus transferring and sharing their  laser technology knowledge between the programs. In another case, the  same contractor is to produce the deformable mirrors used in the ABL and  SBL programs.
All three programs have benefited from the research carried out by the Air  Force Research Laboratory (AFRL).  For example, all programs plan to use  AFRL-developed optical coatings for beam control and laser optical  systems.  With these specialized coatings, optics absorb little energy from a  high energy laser beam, and heavy, vibration-inducing cooling systems are  not needed. AFRL officials have also participated in the three programs in  various ways, which enhances information sharing.  For example, an AFRL  official participating in the ABL program is also acting as a THEL principal  on-site government representative.
section_title: Airborne Laser: Status, Cost, and Technical Challenges
paragraphs: The ABL program is currently in the program definition and risk reduction  (PDRR) acquisition phase.  Initial operational capability of three ABLs is  scheduled for 2007 and full operational capability of seven ABLs is  scheduled for 2009.  This schedule reflects a program slip of about 1 year.   The Air Force estimates the life-cycle cost of the ABL at about $11 billion.
The ABL program has made progress in addressing some technical  challenges, such as atmospheric turbulence that we and others have  reported on in the past.  However, challenges remain because the  components of the system are in various stages of development and have  yet to be produced in their final configurations, tested, and integrated into  an operational weapon system.  Because of the complexity of this  integration, some laser experts both inside and outside of DOD have noted  that the planned flight testing schedule for the program should be  expanded.  We believe that the technical complexity of the ABL and related  integration issues also raises questions about whether the Air Force's  planned ordering of a second aircraft, for modification during the  engineering and manufacturing development (EMD) phase of the program,  is premature.
subsections: section_title: Status and Cost of the ABL Program
paragraphs: In November 1996, the Air Force awarded a 77-month PDRR contract to the  contractor team of Boeing, TRW, and Lockheed Martin.  Under the  contract, Boeing is to produce and modify a 747-400 freighter aircraft and  integrate the laser and beam control system with the aircraft; TRW is to  develop the laser and ground support systems; and Lockheed Martin is to  develop the beam control system.  The PDRR phase includes two interim  milestones--Authority to Proceed 1 (ATP-1), originally scheduled for June  1998, and ATP-2, scheduled for August 2002.  The ABL passed ATP-1 in  September 1998, 3 months late because the flight-weighted laser module  had problems producing the required power level.
The PDRR phase is scheduled to culminate with attempts, in 2003, by the  PDRR ABL aircraft to destroy a boosting theater ballistic missile.  If these  demonstrations are successful, the program is scheduled to move into the  engineering and manufacturing development phase in 2004.  Initial  operational capability of three ABLs is scheduled for 2007; full operational  capability of seven ABLs is scheduled for 2009.  This schedule reflects a  1-year slip in the original PDRR schedule.  According to the program office,  the revision to the schedule is due to a $25-million reduction Congress  made in the fiscal year 1999 appropriation for the ABL and to an expanded  test program.  The Air Force estimates the life-cycle cost of the ABL to be  about $11 billion, including $1.6 billion for the PDRR phase, $1.1 billion for  the EMD phase, $3.6 billion for the production phase, and $4.6 billion for  20 years of operations and support.
ABL Program Progress We reported on the ABL program in October 1997.  At that time, the  immediate area of concern that we and others reported was whether the  program had adequately assessed the adverse effects of atmospheric  turbulence on the ABL's operational effectiveness.  We reported that the  Air Force did not have all of the data needed to fully understand the effect  that atmospheric turbulence would have on the operation of the ABL and  that the Air Force had not determined whether non-optical turbulence  measurements could be correlated to optical turbulence measurements.   We reported that the Air Force had not shown that it could accurately  predict the levels of turbulence the ABL will actually encounter; neither  had it shown that the ABL's technical requirement regarding turbulence  was appropriate.  Consequently, we concluded that it was not yet known  whether the ABL would be able to operate effectively in its operational  environment.  In addition, we reported that the Air Force planned to only  take additional non-optical turbulence measurements to predict the  severity of the optical turbulence the ABL would encounter without first  determining whether the two measurement types could be correlated.
The Air Force has now completed collecting non-optical atmospheric  turbulence data from the Korean and Middle East theaters.  In commenting  on a draft of this report, DOD stated that, while the Air Force's analyses of  these data argue that the design specification established for atmospheric  turbulence is generally accurate, the DOD has yet to reach a final position  on this issue. DOD stated further that it is still examining the design  specification for atmospheric turbulence.  According to DOD, the Air Force  plans to collect and characterize additional data to further validate its  design assumptions.  DOD also stated that uncertainties remain concerning  the ability to use non-optical turbulence measurements under all  conditions to predict operational performance for the ABL.  It said that it  was considering what additional measurements and analysis are needed to  resolve these uncertainties.
The Air Force has also been able to establish that the correlation between  non-optical and optical data is adequate for the purposes of estimating ABL  performance using non-optical data at this stage of the program.  However,  according to DOD officials, there are instances where optical and non- optical data disagree and the causes of these differences are not  understood.  Consequently, the Air Force is continuing to collect and  analyze data to further validate its turbulence design assumptions.
section_title: Technical Challenges Remain
paragraphs: While the ABL program has made progress in addressing technical  challenges relating to atmospheric turbulence, other challenges remain.   Developing a laser module that is of the size and weight that can be carried  by the ABL aircraft (referred to as a flight-weighted laser module), and  integrating the laser, beam control system, and related equipment into an  aircraft, are two examples of these challenges.
subsections: section_title: Flight-Weighted Laser Module Challenges
paragraphs: The technical challenge inherent in the ABL program is exemplified by  problems experienced in developing the high-energy laser.  The Air Force  must build the laser to be able to contend with size and weight restrictions,  motion and vibrations, and other factors unique to an aircraft environment,  yet be powerful enough to sustain a killing force over a range of hundreds  of kilometers.  It is also to be constructed in a configuration that links  modules together to produce a single high-energy beam.  The laser being  developed for the PDRR phase will have six modules.  The laser for the  EMD phase will have 14 modules.  When we issued our report on the ABL  in 1997, the program had constructed and tested a developmental laser  module.  Although that developmental module exceeded its energy output  requirements, it was too heavy and large to meet integration requirements.   It would have to be reduced in width by about one-third and reduced in  weight by over one-half.  To accomplish this, many components of the  module would have to be reconfigured and built of advanced materials,  such as composites.
As previously discussed, the PDRR phase of the ABL program includes two  milestone decision points--referred to as ATP-1 and ATP-2.  To pass ATP-1,  the Air Force had to "demonstrate a single laser module at full power with  all critical components flight-weighted and show performance (power,  beam quality, chemical efficiency, thermal management) is scaleable/ traceable to the EMD design through analysis."  During testing of the flight-weighted laser module in connection with the scheduled June 1998  ATP-1 decision point, the module failed to meet its power output  requirement.  Because of this failure, the program provisionally passed  ATP-1.
The program fully passed ATP-1 when, 3 months later, the laser module  exceeded its power output requirement by 10 percent.  However, the power  output was achieved using a flight-weighted laser module that was not  representative of the laser modules that will be used in an operational ABL  weapon system.  Specifically, the flight-weighted laser module used for  testing in connection with ATP-1 used a stable resonator.  ABL design  specifications require that an unstable resonator be used.  According to  program officials, an unstable resonator is needed because it would  produce a laser beam that would allow the ABL's beam control system to  focus more of the beam's power on the target than would be possible with a  beam produced by a stable resonator.  In commenting on a draft of this  report, DOD stated that a stable, versus unstable, resonator was used for  the initial flight-weighted laser module tests because the test facility had a  stable resonator in place, and to replace the stable resonator with an  unstable resonator would have been too costly and would have adversely  affected the program schedule.
In addition to demonstrating the laser module at full power, ATP-1 also  required the program to demonstrate that the beam quality of the laser  beam generated by the module would meet ABL design requirements.  In  meeting this requirement, the Air Force did not measure the quality of an  actual laser beam generated by the module.  Instead, it estimated the beam  quality using computer models and measurements of the chemical flows  within the laser.  In future tests of the laser module, the Air Force plans to  measure the beam quality of an actual beam generated by the laser module.
In attempting to demonstrate the laser module at full power, the Air Force  identified several design problems.  For example, the catch tank and catch  tank outlet, which collect and recirculate a chemical used by the laser,  were too small.  This limited the flow rate of the chemical, reducing the  laser's power.  Another problem identified was that too much water vapor  entered the laser cavity, which reduced the amount of power generated.  In  addition, gas pressure within the laser cavity was too high, thus slowing the  velocity of gases through the cavity, which also reduced the amount of  power generated.
Some modifications were made to achieve higher power levels during  testing.  These and other modifications are currently being finalized and  incorporated into the flight-weighted laser module.
The ABL program manager stated that integrating a weapon-level laser,  beam control system, and the other related components into an aircraft is  the largest challenge facing the program.  Some individual components of  the ABL have been tested under laboratory conditions and the program  office has conducted modeling and computer simulations.  However, the  individual components have not been integrated and tested as a complete  weapon system.  As we stated in our October 1997 report, until this system  integration and testing is accomplished, it is not possible to predict with  any degree of certainty the probability that the ABL program will evolve  into a viable missile defense system.
A major aspect of this system integration testing will be the hot fire flight  tests when the laser is turned on and the beam is controlled by the beam  control system.  According to planning documents, hot fire flight testing  begins only 4 months prior to the 2003 theater ballistic missile shoot-down  tests.  Because of the complexity of the system integration task, some  experts both inside and outside of DOD have noted that the planned flight  testing schedule for the program is too dependent on successful tests and  does not allow enough time and resources to deal with potential test  failures and to prove the ABL concept.
In a May 1998 Early Operational Assessment, the Air Force Operational  Test and Evaluation Center characterized the flight test schedule as  "compressed and success-oriented."  In addition, the Air Force Scientific  Advisory Board, in its February 1998 report, "Airborne Laser Scenarios and  Concept of Operations," stated that while the ABL program evolution as  currently planned is rational in its sequencing of tests, the schedule  appears to have an unrealistically brief flight testing phase.  The Board  characterized the flight test program as "immature" and said that it needs to  be structured to build high confidence in the operability of the laser  system.  It further stated that past experience with high-power laser  systems and large beam directors suggests that new and difficult problems  will surface in that phase, and that many flights and targets will be needed  to sort them out.  The Board suggested that the laser should be fired a  reasonably large number of times (in the hundreds) with the ABL in flight  before committing to a lethality demonstration and that this would serve to  gain experience; establish that it is safe, reliable, and routine; and measure  the critical parameters that will give a commander the confidence to use  the system without hesitation.  Consequently, the Board advised the Air  Force to develop contingency plans to prepare for the possibility that the  current success-oriented schedule is not achieved, to include ordering  additional long lead targets if required, the identification of potential  avenues of failure during the flight tests, and preparation of work-arounds  or corrective steps prepared in advance.
Congress has also raised concerns related to this issue.  The conference  report on the Strom Thurmond National Defense Authorization Act for  Fiscal Year 1999 noted that the conferees are concerned that the Air Force  plans to enter EMD without adequate time to operate, test, and evaluate the  PDRR configuration.  As a result, the conferees directed the Secretary of  Defense to establish an independent review team to assist with the  Secretary’s evaluation of the technical risk in the ABL program and his  determination of whether (1) additional testing and risk reduction is  necessary prior to integration of the ABL subsystems into a commercial  747-400F aircraft and (2) the fully integrated PDRR aircraft should be  operated for a period of time and thoroughly tested prior to finalizing an  objective design.  The act directed the Secretary of Defense to report the  findings of his assessment of the ABL program by March 15, 1999.
section_title: Planned Ordering of the EMD Aircraft May Be Premature
paragraphs: The technical complexity of the ABL and related integration issues raise  questions about when a second aircraft, for modification during the EMD  phase, should be ordered.  Current program plans call for an aircraft to be  ordered about 1 year before the planned attempts to shoot down a theater  missile with the PDRR aircraft.
The Air Force has a contract with Boeing for the aircraft that will be used  during the PDRR phase.  According to ABL acquisition plans, a second 747-400 freighter will be ordered in September 2002 for the EMD phase.   The ordering of the aircraft is to immediately follow the August 2002 ATP-2  meeting.  However, this acquisition strategy will result in the second  aircraft being ordered about 1 year prior to the scheduled demonstration of  the ABL's ability to shoot down a theater ballistic missile.
section_title: Conclusions
paragraphs: The ABL program has made progress in addressing some technical  challenges, such as atmospheric turbulence, that we and others have  reported on in the past.  However, challenges will continue through the  development program and we have concerns about some Air Force  statements of program successes--specifically, statements related to the  power output and beam quality of the flight-weighted laser module.  Once  these and other problems are resolved, the major program challenge will be  to integrate the individual system components into a complete weapon  system for testing.  A major test for the program will be the flight tests  during which the laser is turned on and its beam is controlled by the beam  control system.  Independent reviews of the ABL program by laser experts  indicate that the ABL flight test plan may be too limited and too dependent  on successful tests, and not allow enough time and resources to deal with  potential test failures and to prove the ABL concept.
The technical complexity of the ABL and related integration issues also  raise questions about when a second aircraft, for modification during the  EMD phase of the program, should be ordered.  Current plans call for the  EMD aircraft to be ordered about 1 year before the PDRR aircraft attempts  to shoot down theater ballistic missiles.  If the PDRR aircraft fails to prove  the ABL concept, the funds expended for the EMD aircraft may be wasted.
section_title: Recommendation
paragraphs: Regarding the ABL program, we recommend that the Secretary of Defense  direct the Secretary of the Air Force to reconsider plans to exercise the  option for the second ABL aircraft for the EMD phase of the program  before flight testing of the ABL system developed during the PDRR phase  has demonstrated that the ABL concept is an achievable, effective combat  system.
section_title: Agency Comments and Our Evaluation
paragraphs: In a draft of this report, we recommended that the Secretary of Defense  direct the Secretary of the Air Force to provide DOD an assessment of the  need to expand the ABL flight test program.  In commenting on that draft  report, DOD partially concurred with our recommendation and stated that  its ongoing assessment of the ABL program by an Independent Assessment  Team (IAT) would constitute an appropriate assessment of the flight test  program.
Subsequent to DOD’s comments on our draft report, DOD completed its  assessment of the ABL program and reported the results to Congress in  March 1999.  In its report, DOD noted the IAT’s agreement with Air Force  plans to restructure the ABL program to expand testing and risk reduction  activities before starting modifications to the PDRR aircraft (the first  aircraft).  DOD concurred with the IAT’s recommendation for more testing  of the PDRR aircraft before Milestone II, which governs entry into  engineering and manufacturing development.  DOD stated that it will  review the Air Force’s proposed restructured program and set a new  Acquisition Program Baseline in the spring of 1999.  During the  restructuring and rebaselining effort, DOD stated that, among other things,  it will revise the exit criteria for Milestone II to require more testing against  threat-representative targets.
DOD stated that it expects that adding flight tests to the program before the  start of EMD will increase near-term costs and might delay ABL’s  achievement of an initial operational capability.  However, according to  DOD, the added tests will ensure that the expenditures required for ABL’s  EMD phase are justified.
We agree with DOD’s assessment and future plans for the ABL program.  Therefore, we deleted from our final report the recommendation for an  assessment of the ABL flight test program.
Based on DOD’s comments on our draft report that DOD would not  necessarily incur unnecessary costs by proceeding with the purchase of a  second ABL aircraft, we revised our recommendation to reflect the need  for DOD to reconsider its planned purchase in light of the IAT’s findings  and our report.
We recognize that delaying the procurement of the aircraft for the EMD  portion of the program until after the ABL demonstrates it can shoot down  target missiles might require a change in the scheduled initial operational  capability.  However, such a slip would ensure that the procurement of the  EMD aircraft would then be based on the additional knowledge gained in  the shoot down demonstrations that the ABL design is feasible.  Our  recommended approach is consistent with DOD’s March 1999 report to  Congress on the ABL program wherein it accepted a potential delay in the  ABL’s initial operational capability in favor of obtaining additional data  through increased flight tests.  Our approach is also appropriate in view of  the discussion in DOD’s March 1999 report on the impact of turbulence on  the ABL design specification.  DOD stated that optical turbulence in excess  of the design specification along the slant path between the ABL and its  target can reduce ABL’s maximum lethal range and increase required dwell  times, even at lesser ranges.  It said that some analyses of atmospheric  turbulence data collected in theaters of interest to date suggest that  turbulence levels well above assumed ABL design levels might occur more  often than expected at the time the design levels were set.  According to  DOD, there are currently no clear methods for predicting the actual  turbulence level along a slant path to a particular threat location at a given  point in time.  Thus, according to DOD, beyond trial and error, it is not clear  how a correct decision can be made on whether a particular target can be  successfully engaged when launched near ABL’s maximum lethal range.   The Air Force is analyzing turbulence data and investigating tactical  decision aids for the system to address this issue.
section_title: Space-Based Laser: Status, Cost, and Technical Challenges
paragraphs: The SBL program is about a year into a $30-million study phase to define  concepts for the design, development, and deployment of an SBL proof of  concept demonstrator.  According to the program office, the SBL  demonstrator would be the most technically complex spacecraft the United  States has ever built.  DOD is currently considering an acquisition strategy  under which the demonstrator spacecraft would be launched in the 2010 to  2012 time frame.  Congress, however, has directed that the demonstrator be  launched in the 2006 to 2008 time frame.
subsections: section_title: Status, Cost, and Technical Challenges
paragraphs: According to a senior SBL program official, the SBL readiness  demonstrator will be the most complex spacecraft the United States has  ever built.  He also said that there is only a 50-percent chance that it will be  built and deployed by 2008.  According to SBL program officials, the weight  and size constraints dictated by the size and weight limitations of existing  and planned launch vehicles force the program to push the state of the art  in areas such as laser efficiency, laser brightness, and deployable optics.   DOD's programmed funding for SBL from fiscal year 1998 to 2005 totals  $1.1 billion.  DOD officials told us that the design, development, and  deployment of an SBL readiness demonstrator would cost about $3 billion.
The conference report for the fiscal year 1998 National Defense  Authorization Act states that the Secretary of Defense, in an August 1997  letter to the Senate Majority Leader, confirmed that SBL technology had  reached a level of maturity that could lead to a future space demonstration  of a sub-scale vehicle.  Consequently, the conferees directed the Air Force  to promptly establish a baseline for a Space-Based Laser Readiness  Demonstrator  (SBLRD) to include a set of technical objectives and  requirements, a contracting strategy, a system design, a program schedule,  and a funding profile that would support a launch in fiscal year 2005.   Further, to ensure the focus of the program remains on a fiscal year 2005  (this deployment date was later changed to the 2006-2008 time frame)  launch, the conferees directed that they be consulted prior to planned  variances from this launch date.  In addition, the conferees directed the  Secretary of Defense to report on the status of the SBL readiness  demonstrator baseline and related issues to the congressional defense  committees by March 1, 1998.  To date, DOD has not submitted its SBL  baseline report to Congress.
In February 1998, the Air Force awarded two 6-month concept definition  study contracts, valued at $10 million each, to Lockheed Martin and TRW  as an initial step to develop SBLRD.  The contractors were tasked to  evaluate three strategies: a 2005/2006 launch of the SBLRD with existing technology, a 2008 launch with existing technology, and a 2008 launch infusing advanced technology.
In early 1998, the Air Force's acquisition strategy was to use evaluation  data from these two efforts, along with other appropriate data, to award a  contract in August 1998 to develop the SBLRD.  The objectives of the  demonstration would be to validate the SBL as a viable option for missile  defense by demonstrating SBL technology readiness and to obtain  performance and operations data regarding high-power space lasers,  long-range precision pointing, adjunct missions feasibility, and to explore  battle management issues.
When the initial acquisition strategy was provided to the Under Secretary  of Defense for Acquisition and Technology in August 1998, the Under  Secretary was concerned that the strategy focused only on the  demonstrator and wanted to know whether the long-term program to  develop and deploy the SBL would be affordable.  Consequently, he  directed the BMDO and the Air Force to restructure and expand the scope  of the readiness demonstrator acquisition strategy to include the complete  development and deployment of an SBL system.  The restructuring was  also to include review and assessment of other missile defense concepts  such as ground-based lasers and space-based relay mirrors.  In addition, the  Under Secretary directed them to look for opportunities to develop  technologies that would increase the affordability of the SBL by  collaborating with other agencies such as the National Aeronautics and  Space Administration, which is currently developing deployable optics for  its next generation space telescope.  In implementing this direction, BMDO  and the Air Force restructured the acquisition strategy and extended the  concept definition study contracts at a cost of $5 million each.  In February  1999, BMDO and the Air Force announced the award of a contract for a  joint venture among Boeing, Lockheed Martin, and TRW for $125 million  for initiating the Space-Based Laser Integrated Flight Experiment effort  that is to result in deploying the readiness demonstrator in the 2010 to 2012  time frame.  According to BMDO officials, a full SBL system would not be  deployed until after 2020.
section_title: Conclusions
paragraphs: The future of the SBL program is unknown at this time.  DOD is currently  doing a comprehensive assessment of the program.  That assessment will  include alternative ballistic missile defense concepts, such as ground-based  lasers and space-based relay mirrors.  If, based on this assessment, the SBL  is ultimately selected, DOD estimates that a fully operational system would  not be deployed until after 2020.  Accelerating the deployment date would  require the maturation of some complex technologies such as deployable  optics and would require a large, but yet unknown, infusion of funds into  the program.
section_title: Tactical High Energy Laser: Status, Cost, and Technical Challenges
paragraphs: The THEL is about 34 months into its $131.5 million 38-month development  program.  All of its components--such as the laser, the pointer tracker, and  the pressure recovery system--have been built and are currently being  tested.  The system was scheduled to be integrated, tested, and ready to  begin shoot-down tests against short-range rockets at White Sands Missile  Range by December 1998. However, the shoot-down testing has been  delayed 7 months due to administrative issues and technical problems with  the laser and the pointer tracker.
Although THEL's components have been produced, the technical  challenges relating to testing and integration remain to be overcome.   Initial testing of the laser has identified a problem with the chemical flow  control valves.  In addition, tests of the pointer tracker have identified  problems with the low-power laser that is to track short-range rockets.   Furthermore, integration and related testing have yet to begin.
subsections: section_title: Status and Cost of the THEL Program
paragraphs: In May 1995, a predecessor program to THEL, Nautilus, was started.  Nautilus was a joint U.S.-Israel program to evaluate the effectiveness of  lasers for potential use as a tactical air defense system against short-range  rockets in a variety of missions, including peace-keeping operations.  The  U.S. Army Space and Missile Defense Command (SMDC), then called the  Space and Strategic Defense Command, provided primary management  functions for the program.  The Israel Ministry of Defense provided support  to SMDC. In February 1996, the Nautilus program culminated in a  successful test at the Army's High Energy Laser Systems Test Facility  (HELSTF) at White Sands Missile Range, New Mexico, using the Mid- Infrared Advanced Chemical Laser and Sea Lite Beam Director to engage  and destroy a short-range Katyusha rocket.
In April 1996, President Clinton met with Israel's then Prime Minister  Shimon Peres.  At the meeting, the United States made a commitment to  assist Israel to develop a Tactical High Energy Laser Advanced Concept  Technology Demonstrator.  This commitment, based on the success of the  Nautilus program, was designed to help Israel defend its northern cities  from the threat posed by Katyusha and other short-range rockets.
In May 1996, TRW was awarded a contract for $89 million to design,  fabricate, and test a tactical-sized deuterium fluoride chemical laser  capable of defeating short-range artillery rockets.  The original contract  called for about a 22-month effort to design and build the system by March  1998.  Israel contributed $24.7 million toward the contract cost and  developed components such as the fire control radar system, laser fluid  supply system, and pressure recovery system (laser exhaust system).  In  January 1998, the contract was modified to increase its value by $42.5 million to $131.5 million (increasing the U. S. contribution to  $106.8 million) and to extend the completion date by 11 months to  February 1999 for integration and rocket shoot-down testing at HELSTF.   This testing was scheduled to begin in December 1998.  However, testing of  the laser and the pointer tracker has revealed problems that have, along  with administrative issues associated with contract initiation, caused the  schedule to be delayed by 7 months, to July 1999.
subsections: section_title: Technical Challenges Facing the THEL Program
paragraphs: THEL's components have been produced.  However, initial testing of the  laser has identified problems with the operation of chemical flow control  valves and with the low-power laser that is to be used in tracking the  short-range rockets.
The initial tests of the laser revealed leaks in the specialized valves that  control the flow of chemicals through the laser.  These leaks must be  corrected because they would detract from the performance of the laser.   In addition, testing of the pointer tracker system disclosed a problem with  the low-power laser that is to be used in tracking incoming short-range  rockets.  This laser is a commercial off-the-shelf item that is generally used  in laboratory settings.  It has been modified for use on the THEL; however,  it is still undergoing tests to ensure it meets performance requirements.
The valve leaks and the problems with the low-power laser in the pointer  tracker system have caused a delay in the THEL test schedule.  Originally,  the THEL system was scheduled to be a fully integrated system that would  attempt to shoot-down a Katyusha rocket at HELSTF in December 1998.   Because of these unanticipated problems and administrative issues, the  schedule has slipped by 7 months, to July 1999.
section_title: A U.S. Requirement for THEL-Type System Would Present Additional Technical Challenges
paragraphs: Currently, U.S. forces do not have a validated mission requirement for the  THEL as it is being designed for Israel.  However, the Army has prepared a  draft mission needs statement for a reconfigured mobile laser weapon that  could be used by U.S. forces to shoot down a variety of targets in theater  environments.  A THEL official told us that the draft Army mission needs  statement is being incorporated into Atlantic Command's Joint Theater and  Missile Defense mission needs statement, which includes the need for a  mobile high-energy laser weapon.
The THEL would have to be radically modified for it to be more powerful  and mobile and thus meet emerging U.S. theater defense requirements for a  ground-based laser.  While the THEL system being developed for Israel is  designed to be transportable, it will not be mobile; THEL components must  be transported by large trucks and placed on prepared concrete sites.   According to laser experts at Lawrence Livermore National Laboratory, a  mobile, ground-based high-energy laser weapon for U.S. use would  probably necessitate using a relatively small solid-state laser (versus the  much larger and heavier chemical laser being developed for the THEL), the  technology for which is relatively immature.  The experts said that a  generation of solid-state laser research and development would be needed  to develop technology to the level necessary for use in a mobile THEL-type  system.  A program official said that such a system would probably not be  fielded until at least 2025.  In commenting on a draft of this report, DOD  stated that the Army is investigating four solid-state laser concepts and the  availability dates and concepts may be different than the assessment  provided by Lawrence Livermore National Laboratory officials.
section_title: Conclusions
paragraphs: Of the three laser weapon systems that DOD is developing for use against  theater ballistic missiles or short-range artillery rockets, the THEL is  closest to becoming a fielded system.  It is being developed in a relatively  short time frame at a relatively low cost.  Because THEL is a follow-on to  an earlier laser weapon program, its successful development and fielding  have been considered relatively low risk.  However, technical problems and  their associated program delays demonstrate the complex nature of  developing laser weapons of this type.  Lessons learned from the THEL  program will be beneficial if the United States decides to develop a THEL- type system for its military forces.  However, given the more demanding  requirements that the U.S. will likely have, eventual success of the THEL  program will not easily translate into a low-risk, problem-free U.S.  program.
section_title: Comments From the Department of Defense
paragraphs: The following are GAO’s comments on the Department of Defense’s (DOD)  letter dated February 19, 1999.
subsections: section_title: GAO Comments
paragraphs: 1.  The Secretary of Defense submitted his report on the Airborne Laser  (ABL) program to Congress in March 1999, subsequent to DOD providing  comments on a draft of this report.  The Secretary reported that the ABL  flight-test program will be expanded.  Since this action is consistent with  the recommendation in our draft report, we have deleted the  recommendation from the final report. 2.  We agree that operational testing for the ABL program will not begin  until the engineering and manufacturing development (EMD) phase and  have modified the text by deleting the word operational.  However, we  retained the term combat system because it refers to the ABL concept and  not to the program definition and risk reduction (PDRR) aircraft. 3. We have modified the report to clarify that the Space-Based Laser (SBL)  is a demonstration program.  4. We have modified the report title and text to clarify that the Tactical  High-Energy Laser (THEL) is not a theater ballistic missile defense system. 5.  We have modified the text of the report to reflect that DOD has not yet  reached a final position on the issue of atmospheric turbulence. 6.  We did not assess the marketability of the 747 freighter aircraft by the  Air Force if it decides to terminate or delay the ABL program.  However, if  after ordering the aircraft DOD decides to terminate the program, it would  be liable for up to $50 million unless it can successfully sell its place in the  production queue or sell the aircraft.  DOD did not include in its comments  an estimate to store the aircraft if the ABL program is delayed.
section_title: Major Contributors to This Report
subsections: section_title: National Security and International Affairs Division, Washington, D.C.
paragraphs: Ted B. Baird Rich Horiuchi The first copy of each GAO report and testimony is free. Additional copies are $2 each.  Orders should be sent to the  following address, accompanied by a check or money order made  out to the Superintendent of Documents, when necessary, VISA and  MasterCard credit cards are accepted, also.
Orders for 100 or more copies to be mailed to a single address are  discounted 25 percent.
U.S. General Accounting Office P.O. Box 37050 Washington, DC  20013 Room 1100 700 4th St. NW (corner of 4th and G Sts. NW) U.S. General Accounting Office Washington, DC Orders may also be placed by calling (202) 512-6000 or by using fax number (202) 512-6061, or TDD (202) 512-2537.
Each day, GAO issues a list of newly available reports and  testimony.  To receive facsimile copies of the daily list or any list  from the past 30 days, please call (202) 512-6000 using a touchtone  phone.  A recorded menu will provide information on how to obtain  these lists.