Tactical Aircraft: DOD Should Reconsider Decision to Increase F/A-22 Production Rates While Development Risks Continue
Published: 2003-03-14T00:00:00

Fast Facts:

Highlights:
section_title: Why GAO Did This Study
paragraphs: The Air Force is developing the F/A-22 aircraft to fly at higher speeds for longer distances, be less detectable, and improve the pilot's awareness of the surrounding situation. The F/A-22 will replace the Air Force's existing fleet of F-15 aircraft. Over the past several years the program has experienced significant cost overruns and schedule delays. Congress mandated that GAO assess the development program and determine whether the Air Force is meeting key performance, schedule, and cost goals. GAO also assessed the implications of the progress of the development program on production.
section_title: What GAO Found
paragraphs: The F/A-22 development program did not meet key performance, schedule, and cost goals in fiscal year 2002, and delays in the flight test program have led to an increase in the development cost estimate of $876 million. In response to this increase, DOD restructured the development program and reduced production aircraft by 27. If additional delays occur, further changes may be required. The program also continues to address technical problems that have limited the performance of test aircraft, including violent movement or "buffeting" of the vertical fins, overheating in portions of the aircraft, weakening of materials in the horizontal tail, and instability of avionics software. Air Force officials cannot predict when they will resolve these problems. These technical problems, along with the late delivery of aircraft to the flight test center, have delayed the development program. Based on F/A-22 flight test accomplishment data and current flight test plans, we believe that operational testing will likely be delayed several months beyond the planned August 2003 start date. The F/A-22 program is in its final stages of development, and low-rate initial production has begun. Since fiscal year 1997, funds have been appropriated to acquire production aircraft, and the F/A-22 acquisition plan calls for steadily increasing annual production rates. However, GAO considers the Air Force's acquisition strategy at high risk for increases in production costs. In past reports, GAO has reported that acquiring aircraft while significant technical challenges remain does not allow for adequate testing of the aircraft. The uncertainties regarding performance capabilities of the F/A-22 aircraft and its development schedule will persist until technical problems have been addressed, including testing of modifications or fixes necessary to potentially alleviate these problems. In light of those uncertainties, steadily increasing annual production rates could result in the Air Force having to modify a larger quantity of aircraft after they are built.

section_title: Letter
paragraphs: The Air Force is developing the F/A-22 aircraft to replace its fleet of F-15  air superiority aircraft. The F/A-22 is designed to be superior to the  F-15 because it is capable of flying at higher speeds for longer distances,  more difficult to detect, and able to provide the pilot with substantially  improved awareness of the surrounding situation. The Air Force began the  F/A-22 development program in 1991. During the past several years, the  program has experienced repeated and significant cost overruns and  schedule delays. Congressional concern about the aircraft’s development  program cost and progress is long-standing, and it continues.
The National Defense Authorization Act for Fiscal Year 1998 requires  us to assess the Air Force’s F/A-22 development program annually and  determine whether the Air Force is meeting key performance, schedule,  and cost goals. This is our fifth report. Specifically, we determined (1) the  progress of F/A-22 development in terms of performance, schedule, and  cost and (2) implications of this progress on the Department of Defense’s  (DOD) acquisition plans.
subsections: section_title: Background
paragraphs: The F/A-22 is to be an air superiority and ground attack aircraft with  advanced features to make it less detectable to adversaries (stealth  characteristics) and capable of high speeds for long ranges. It is designed  to have integrated avionics that greatly improve pilots’ awareness of the  situation surrounding them. The objectives of the F/A-22 development  program are to (1) design, fabricate, test, and deliver nine F/A-22  development test aircraft, two non-flying structural test aircraft, six  production representative test aircraft, and 37 flight-qualified engines;  (2) design, fabricate, integrate, and test the avionics; and (3) design,  develop, and test the support and training systems. The F/A-22 is being  developed under contracts with Lockheed Martin Corporation, the prime  contractor (for the aircraft), and Pratt & Whitney Corporation (for  the engine).
Following a history of increasing cost estimates to complete the  development phase of the F/A-22 program, the National Defense  Authorization Act for Fiscal Year 1998 established a cost limitation for  both the development and production. Subsequently, the National  Defense Authorization Act of 2002 eliminated the cost limitation for the  development, but left the cost limit for production cost in place. The  production program is now limited to $36.8 billion. The current cost  estimate of the development program is $21.9 billion.
Currently, the F/A-22 program is in both development and production.  Development is in its final stages, and low rate initial production has  begun. Since fiscal year 1997, funds have been appropriated to acquire  production aircraft, and the F/A-22 acquisition plan calls for steadily  increasing annual production rates.
The aircraft’s development problems and schedule delays have caused  congressional concerns, particularly in light of DOD’s planned increase in  production rates. The National Defense Appropriations Act for Fiscal Year  2003 prohibited the obligation of funds for the acquisition of more than  16 production aircraft in fiscal year 2003, until the Under Secretary of  Defense for Acquisition, Technology, and Logistics submits the following  to the congressional defense committees: (1) a formal risk assessment that  identifies and characterizes the potential cost, technical, schedule, or  other significant risks resulting from increasing the F/A-22 production  quantities prior to the Dedicated Initial Operational Test and Evaluation  (DIOT&E) of the aircraft and (2) either a certification that increasing the  F/A-22 production quantity for fiscal year 2003 beyond 16 aircraft involves  lower risk and lower total program cost than staying at that quantity or  implementing a revised production plan, funding, and test schedule. In  December 2002, DOD submitted the risk assessment and certification  to Congress.
section_title: F/A-22 Technical Problems Continue to Affect Performance
paragraphs: The F/A-22 developmental program did not meet key performance goals  established for fiscal year 2002 and continues to confront numerous  technical challenges. Major technical problems include instability of the  avionics software, violent movement, or “buffeting,” of vertical fins,  overheating in portions of the aircraft, weakening of materials in the  horizontal tail, and the inability to meet airlift support and maintenance  requirements. Modifications are being made to some test aircraft to  address some of these problems in preparation for operational testing.  Nevertheless, these problems continue to restrict the performance and  testing of the F/A-22.
subsections: section_title: Avionics Instability
paragraphs: Software instability has hampered efforts to integrate advanced avionics  capabilities into the F/A-22 system. Avionics control and integrated  airborne electronics and sensors provide an increased awareness of the  situation around the pilot. The Air Force told us that the avionics have  failed or shut down during numerous tests of F/A-22 aircraft due to  software problems. The shutdowns occur when the pilot attempts to use  the radar, communication, navigation, identification, and electronic  warfare systems concurrently. Although the plane can still be flown after  the avionics have failed, the pilot is unable to successfully demonstrate the  performance of the avionics. Therefore, the Air Force has had to extend  the test program schedule.
The Air Force recognized that the avionics problems pose a high technical  risk to the F/A-22 program, and in June 2002 the Air Force convened a  special team to address the problem. According to the team, the  unpredictable nature of the shutdowns was not surprising considering the  complexity of the avionics system. The team recommended that the  software be stabilized in the laboratory before releasing it to flight testing.  The team further recommended conducting a stress test on the software  system architecture to reduce problems and ensure that it is operating  properly. The Air Force implemented these recommendations. Further, the  Air Force extended the avionics schedule to accommodate avionics  stability testing and now plans to complete avionics testing in the first  quarter of 2005. However, Air Force officials stated that they do not yet  understand the problems associated with the instability of the avionics  software well enough to predict when they will be able to resolve  this problem.
section_title: Vertical Fin Buffeting
paragraphs: Under some circumstances, the F/A-22 experiences violent movement, or  buffeting, of the vertical fins in the tail section of the aircraft. This occurs  as air, moving first over the body and the wings of the aircraft, places  unequal pressures on the vertical fins and rudders. Unless the violent  movement is resolved or the fins strengthened, the vertical fins will break  over time because the pressures experienced exceed the strength limits of  the fins. In addition, the buffeting problem has restricted the testing of  aerial maneuvers of the aircraft.
Lockheed Martin has developed several modifications to strengthen the  vertical fins and has performed an analysis to test the structural strength  of the aircraft. It concluded that no flight restrictions above 10,000 feet are  necessary as a result of buffeting. Currently, the Air Force has not begun  testing to verify flight operations at or below 10,000 feet; operational  limitations at altitudes below 10,000 feet remain in effect, with testing  scheduled to begin in June 2003.
section_title: Overheating Concerns
paragraphs: Overheating in the rear portions of the aircraft has significantly restricted  the duration of high-speed flight testing. As the F/A-22 flies, heat builds up  inside several areas in of the rear of the aircraft. Continued exposure to  high temperatures would weaken these parts of the aircraft. For example,  a portion of the airframe that sits between the engines’ exhausts  experiences the highest temperatures. This intense heat could weaken or  damage the airframe. To prevent this heat buildup during flight testing, the  aircraft is restricted to flying just over 500 miles per hour, about the same  speed as a modern jet liner, and significantly below the supercruise  requirement. Currently, the F/A-22 flies with temperature sensors in  those areas of the aircraft, and it slows down whenever the temperature  approaches a certain level. The Air Force may add copper sheets to the  rear of the aircraft to alleviate the problem. The Air Force began these  modifications in January 2003 and plans to complete them by July 2003.
section_title: Horizontal Tail Material Separations
paragraphs: F/A-22 aircraft have experienced separations of materials in the horizontal  tail and the shaft, which allows the tail to pivot. Because the separations  reduce tail strength, the Air Force restricted flight testing of some aircraft  until it determined that this problem would not affect flight safety  during testing. The Air Force and the contractor initially believed that  improvements to the aircraft’s manufacturing process would solve this  problem. However, the Air Force has determined that it could only solve  this problem by redesigning the tail of the aircraft. The Air Force plans to  conduct flight testing of the redesigned tail between February 2004 and  April 2004.
section_title: Meeting Airlift Support Requirements
paragraphs: The Air Force estimates it will not meet the F/A-22 airlift support  requirement despite last year’s estimate that it would meet all identified  key performance parameters. (Appendix I contains a list of key  performance parameters.) The airlift support requirement is that 8 C-141  aircraft or their equivalents would be sufficient to deploy a squadron of  24 F/A-22s for thirty days without resupply. Today the Air Force estimates  that 8.8 C-141 equivalents will be necessary.
section_title: Impact of Maintenance Needs on Performance
paragraphs: The F/A-22’s performance may also be affected by maintenance needs  that exceed established objectives. The Air Force estimates that the  F/A-22 should, at this point in its development, be able to complete  1.67 flying hours between maintenance actions and 1.95 flying hours by  the end of development. However, aircraft are requiring five times the  maintenance actions expected at this point in development. As of  November 2002, the development test aircraft have been completing  only .29 flying hours between maintenance actions. Therefore, the  development test aircraft are spending more time than planned on the  ground undergoing maintenance.
In addition, the F/A-22 program has not completed the testing required to  prove the aircraft can be maintained worldwide without unique support  equipment. For example, the Air Force planned to fly the F/A-22 a  minimum of 650 hours prior to the start of operational testing to establish  that special support equipment is not necessary to maintain the materials  on the exterior of the aircraft. These materials are critical to the aircraft’s  low observable, or stealthy, nature. However, as of December 2002, the  program has only accomplished 191.6 hours. According to the Air Force,  the program will not complete testing for this requirement until the  completion of the development program, currently planned for July 2004.
section_title: Modifications to Improve Performance
paragraphs: In 2002, the F/A-22 development program implemented several  modifications to development aircraft to improve performance. The  majority of modifications were related to installing the necessary upgrades  to complete operational testing. The last three development test aircraft  have required an average of 63 modifications. The first two production  aircraft have required an average of 50 of these upgrades.
In addition, the program repaired problems in the aircraft’s arresting gear  system that were discovered during development testing. Further, the Air  Force has scheduled modifications to address the previously cited  problems found with the vertical tail of the aircraft (fin-buffeting). The Air  Force included these repairs in its 2002 modification schedule, but did not  begin them in 2002. The modifications will begin during fiscal year 2003.
section_title: Flight Test Schedules Have Been Extended and May Slip Further
paragraphs: Progress in F/A-22 flight testing was slower than expected in 2002 in all  test areas, according to Office of the Secretary of Defense (OSD) testing  officials. Consequently, the Air Force extended flight test schedules and  reduced the number of flight tests. Many tasks originally planned for 2002  were rescheduled for 2003. Further, the Air Force now plans to conduct  more developmental flight testing concurrently with operational testing.
Continuing technical problems were the primary reasons for the delays  in flight testing. In addition, late delivery of development aircraft to the  flight test center was a contributing problem; three developmental aircraft  were delivered from 9 to 12 months late. Late deliveries were due not  only to technical problems, but also to continuing problems associated  with the manufacture and assembly of development aircraft by the  prime contractor.
With the new schedule, the Air Force delayed the beginning of operational  testing for 4 months, until the portion of developmental testing required to  begin operational testing could be completed. Operational testing is now  planned to begin in August 2003. Figure 1 and table 1 show the changes in  the FA/-22 flight test schedules.
However, according to OSD officials involved in operational testing, there  is a high risk of not completing an adequate amount of development flight  testing before operational testing is scheduled to begin. Indeed, we believe  that it is unlikely that the Air Force will be able to complete all necessary  avionics flight testing prior to the planned start of operational testing.  Based on F/A-22 flight test accomplishment data and current flight test  plans, we project that the start of operational testing might be delayed  until January 2004. As a result, operational testing could be delayed by  several months beyond the current planned date of August 2003.
section_title: Development and Modernization Costs Have Increased
paragraphs: In December 2002, the Air Force estimated that development costs had  increased by $876 million, bringing total development costs to  $21.9 billion. This increase was due to the technical problems and  schedule delays discussed earlier.
In addition, since fiscal year 2001, there have been dramatic increases  in planned funding for modernization upgrades that enhance the  operational capabilities of the F/A-22, as shown in figure 2. Currently, the  Air Force has almost $3.0 billion in funding for modernization projects,  which it plans to spend through fiscal year 2009. Most of the recent  increase in modernization funding is necessary to provide increased  ground attack capability. Other modernization projects include upgrading  avionics software, adding an improved short-range missile capability,  upgrading instrumentation for testing, and incorporating a  classified project.
In December 2002, in response to the increase in development costs, the  Under Secretary of Defense, Comptroller, approved the restructuring of  the F/A-22 program. According to the Comptroller, the cost increase will  not require increased funds from Congress. Rather, the estimated  $876 million increase for development will be met by a $763 million  decrease in production funding and a transfer of $113 million from  modernization funds. This restructure eliminates 27 aircraft from the  current production program, reducing the total number of aircraft to be  acquired from 303 to 276.
section_title: Risks in the F/A-22 Acquisition Plan
paragraphs: Despite continuing development problems and challenges, the Air Force  plans to continue acquiring production aircraft at increasing annual rates.  This is a very risky strategy, because, as we have previously reported,  the Air Force may encounter higher production costs as a result of  acquiring significant quantities of aircraft before adequate testing. Late  testing could identify problems that require costly modifications in order  to achieve satisfactory performance.
For example, as shown in figure 3, the Air Force plans to acquire  20 aircraft during 2003, rather than the maximum of 16 Congress allowed  without DOD’s submittal of a risk assessment and certification. DOD  justified this strategy in the December 2002 risk assessment and  certification it submitted to Congress. In this document, DOD certified  that acquiring more than 16 aircraft involved lower risk and lower total  program cost than acquiring only 16. DOD identified the costs associated  with acquiring more than 16 aircraft per year as between $7 million and  $221 million, depending on the number of aircraft in excess of 16. DOD  concluded that this additional cost would be less than the potential cost of  modifying production aircraft once operational testing has been  completed. Figure 3 shows the Air Force’s acquisition plan.
However, DOD’s risk assessment may be overly optimistic because it  is grounded in the conclusion that there is a low risk that remaining  development and operational testing will identify needs for expensive  modifications. The performance capabilities of the F/A-22 and its schedule  will remain uncertain until technical problems have been addressed,  including testing of modifications or fixes necessary to potentially  alleviate these problems. Furthermore, we believe that the amount of  development and operational testing and the remaining uncertainties  increase the possibility that modifications considered unlikely in DOD’s  analysis will, indeed, need to be made. For example, the Air Force has still  not completely defined the fin-buffet problem described earlier in this  report. The remaining 15 percent of flight testing to help characterize the  problem is not scheduled to begin until June 2003. Consequently, there is  still the possibility that additional modifications and costs may be  necessary to correct this problem on production aircraft. DOD’s risk  assessment acknowledges that additional fin buffet testing is needed, but  concludes that modifications are not expected.
The optimism of DOD’s risk assessment is reflected in the Air Force’s  general acquisition strategy. As also shown by figure 3, the Air Force  is currently committed to acquiring 73 production aircraft (26 percent)  before operational and development testing is complete. We believe that— like the fiscal year 2003 decision to acquire more than 16 aircraft—this is  an overly optimistic strategy given the remaining F/A-22 technical  problems and the current status of testing. As we have noted, acquiring  aircraft before completing adequate testing to resolve significant technical  problems increases the risk of costly modifications later. If F/A-22 testing  schedules slip further—as we believe is likely—even more aircraft will be  acquired before development and operational testing is complete, and the  risk of costly modifications will increase still more.
section_title: Conclusions
paragraphs: Continuing the acquisition of aircraft in increasing quantities when  significant development testing and technical problems remain is an  acquisition strategy that relies on overly optimistic assumptions regarding  the outcome and timing of the remaining testing events. By employing  such a strategy, major problems are more likely to be discovered after  production has begun when it is either too late or very costly to correct  them. At the very least, key decisions are being made without adequate  information about the weapon system’s demonstrated operational test  results. In its certification, DOD quantified the estimated costs associated  with a higher production rate. However, the potential advantage was  predicated on the assumption that the risks of modifications are low.  As we stated last year, by limiting F/A-22 production quantities and  completing development testing, the Air Force could gain information that  would reduce uncertainties and the risks of increased costs and delays  before committing to additional production aircraft. As we discussed  earlier in this report, DOD recently decided to reduce production  quantities as part of a program restructure to address F/A-22 development  problems and associated cost increases. Based on uncertainties about the  resolution of problems found in the past year, we continue to maintain the  position that production quantities should be limited.
section_title: Recommendations for Executive Action
paragraphs: In light of continued uncertainties regarding the resolution of problems  found in the past year and notwithstanding the December 2, 2002  certification provided by DOD, we recommend that the Secretary of  Defense  reconsider the Department’s decision to increase the annual  production rate beyond 16 aircraft until greater knowledge on any  need for modifications is established through completion of  operational testing, and    update the 2002 risk assessment and certification with sufficient detail to  allow for verification of the conclusions following the completion of  operational testing.
section_title: Agency Comments and Our Evaluation
paragraphs: In written comments on a draft of this report, DOD stated that it agreed,  for the most part, with our description of the current state of the F/A-22  program’s content, schedule, and cost. However, DOD did not concur with  our recommendation that it not increase its production rate beyond the  maximum of 16 aircraft Congress allowed without DOD submitting a risk  assessment and certification. DOD said that our recommendation does not  sufficiently account for the costs of termination associated with the  approval given to funding long-lead items, the manufacturing inefficiencies  associated with a reduction in aircraft quantities, or the effects of inflation  on the cost of acquiring aircraft at a lower rate. DOD also noted that we  had not provided a quantitative assessment to justify limiting production,  and it reiterated its reliance on the risk assessment and certification it  submitted to Congress in December 2002. DOD also asserted, incorrectly,  that our report concludes that minimal cost risk would be realized by  slowing production.
Following review of DOD’s comments, we clarified the recommendation  in our draft report by establishing two recommendations. These  recommendations are based on the current state of the program— including the challenges and risks it faces—and on our examination of  DOD’s risk assessment and certification. DOD acknowledges the  challenges faced by the program but believes the risk of modification is  low. As we discussed in this report, until testing has been completed and  technical problems have been addressed, the performance capabilities  of the F/A-22 and its schedule will remain uncertain; thus, it is not possible  to predict that expensive modifications will not be required. For example,  as we stated earlier in this report, DOD’s risk assessment concludes that  significant costs associated with a more extensive modification to resolve  the fin buffet problem may be required, but the probability is low. DOD  arrives at this conclusion even though the last phase of testing to help  characterize the fin buffet problem has not yet begun. Furthermore, we  continue to believe there is still significant risk that the F/A-22 program  will not be able to begin operational testing as scheduled in August 2003.  Subsequent to our providing the draft of this report to DOD for comment,  OSD’s operational test and evaluation office issued a report stating that  F/A-22 technical and schedule risk are still high, as is the risk that  operational testing will be further delayed.
While DOD’s December 2002 risk assessment and certification did provide  an indication that manufacturing inefficiencies and inflation as a result of  lower production rates would increase costs, sufficient detail was not  provided in its risk assessment for us to verify DOD’s conclusion. We  requested additional detailed information to help us evaluate and verify  the conclusions. However, the information provided to us was not  adequate to verify the conclusions contained in the risk assessment.  Regardless, even with such verification, still needing to be resolved are the  uncertainties to date regarding when development problems can be fixed  and the possibility of finding additional problems prior to the completion  of operational testing. As a result, we have little confidence that existing  problems can be quickly resolved and will not result in further delays. Our  work has shown that continuing the acquisition of aircraft in increasing  quantities when significant development testing and technical problems  remain is risky. By employing such a strategy, major problems are more  likely to be discovered after the program has begun production when it is  either too late or very costly to correct them.
DOD also provided various technical comments, which we have  incorporated as appropriate. One of these comments related to the total  number of production aircraft to be acquired. The projected number of  production aircraft the Air Force plans to or can actually acquire has  historically been fluid and elusive. For example, the President’s budget  for fiscal year 2003 reflected plans to acquire 333 production aircraft,  even though the approved program at the time called for acquiring  295 production aircraft. In its technical comments, DOD stated that the  approved program plan is to acquire 295 aircraft. As a result of the recent  F/A-22 restructuring to cover development cost increases, the Air Force  says that it now plans to acquire 276 aircraft. However, DOD estimates  that the cost of production to acquire these 276 aircraft will be  $42.2 billion, which exceeds the current production cost limit by  $5.4 billion. Consequently, unless the production cost limit is raised or  substantial cost reduction plans are achieved, it appears that the number  of aircraft that can actually be purchased will have to be lowered from  the 276 planned. This is particularly true if production or development  costs—or both—continue to rise and no additional funds are provided by  the Congress.
Last month, we recommended in another report that DOD provide  Congress with documentation reflecting the quantity of aircraft that DOD  believes can be procured within the existing production cost limit. DOD’s  explanation in its technical comments to a draft of this report identifies  the likelihood that F/A-22 aircraft quantities will continue to fluctuate. This  makes our recent recommendation that much more compelling.
section_title: Scope and Methodology
paragraphs: To determine whether the development program is likely to meet  performance goals, we analyzed information on the status of key  performance parameters. We compared performance goals established by  the Under Secretary of Defense for Acquisition, Technology, and Logistics  with the Air Force’s estimates of performance for completion of  development made in December 2002.
To identify the status of F/A-22 modifications, we collected updated  information on the status of existing aircraft structural problems that  have required aircraft modifications. To determine whether the program  is expected to meet schedule goals, we reviewed program and avionics  schedules and discussed potential changes to these schedules with F/A-22  program officials. We tracked progress in the flight test program and  evaluated schedule variances in the contractors’ performance  management system and compared planned milestone accomplishment  dates with actual dates. We tracked technical problems in manufacturing  and assembling the development test aircraft.
To determine whether the program is likely to meet the cost goal, we  examined (1) the extent to which the development program is likely to be  completed within the current cost estimate, (2) the Air Force’s plans to  fund the program for fiscal year 2003, and (3) the program’s funding plan  compared to the current cost estimate.
In examining DOD’s risk assessment, we discussed the various DOD  assumptions and approaches used in the assessment with a program  official who conducted the assessment. We then analyzed the various DOD  assumptions and approaches used to make the assessment conclusions.
In making these determinations, assessments, and identifications, we  required access to current information about test results, performance  estimates, schedule achievements and revisions, costs being incurred,  aircraft modifications, and the program’s plans for continued development  and initial production. The Air Force and contractors gave us access to  sufficient information to make informed judgments on the matters covered  in this report.
In performing our work, we obtained information or interviewed officials  from the Office of the Secretary of Defense, Washington, D.C., and the  F/A-22 System Program Office, Wright-Patterson Air Force Base, Ohio. We  performed our work from September 2002 through December 2002 in  accordance with generally accepted government auditing standards.
We are sending copies of this report to interested congressional  committees; the Secretary of Defense; the Secretary of the Air Force; and  the Director, Office of Management and Budget. We will also make copies  available to others upon request. In addition, the report will be available at  no charge on the GAO Web site at http://www.gao.gov. Please contact me  at (202) 512-4841 or Catherine Baltzell at (202) 512-8001 if you or your staff  have any questions concerning this report. Major contributors to this  report are listed in appendix III.
section_title: Appendix I: Estimates of Performance for Key Parameters
subsections: section_title: Combat radius sub + super Radar detection range Independent airlift support (C-141 equivalents) Sortie generation rate Average flight test hours between maintenance Interoperability
paragraphs: Margin  Favorable  12% favorable  3% favorable  0  NA  15% favorable  5% favorable  (0.8) unfavorable  0  0  0  The acceleration parameter is a measure of the time it takes the aircraft to increase speed to a  certain level. If the aircraft is able to increase speed to a certain level in less time than expected,  this is considered favorable. Therefore, a measure of less than 100 percent is favorable.
section_title: Appendix II: Comments from the Department of Defense
section_title: Appendix III: GAO Staff Acknowledgments
subsections: section_title: Acknowledgments
paragraphs: Catherine Baltzell, Marvin E. Bonner, Edward Browning, Gary Middleton,  Sameena Nooruddin, Madhav Panwar, Karen A. Richey, Don M.  Springman, and Ralph White made key contributions to this report.
section_title: Related GAO Products
paragraphs: Tactical Aircraft: F-22 Delays Indicate Initial Production Rates Should  Be Lower to Reduce Risks. GAO-02-298. Washington, D.C.: March 5, 2002.
Tactical Aircraft: Continuing Difficulty Keeping F-22 Production Costs  Within the Congressional Limitation. GAO-01-782. Washington, D.C.:  July 16, 2001.
Tactical Aircraft: F-22 Development and Testing Delays Indicate Need  for Limit on Low-Rate Production. GAO-01-310. Washington, D.C.:  March 15, 2001.
Defense Acquisitions: Recent F-22 Production Cost Estimates  Exceeded Congressional Limitation. GAO/NSIAD-00-178.  Washington, D.C.: August 15, 2000.
Defense Acquisitions: Use of Cost Reduction Plans in Estimating  F-22 Total Production Costs. GAO/T-NSIAD-00-200. Washington, D.C.:  June 15, 2000.
Budget Issues: Budgetary Implications of Selected GAO Work for  Fiscal Year 2001. GAO/OCG-00-8. Washington, D.C.: March 31, 2000.
F-22 Aircraft: Development Cost Goal Achievable If Major Problems Are  Avoided. GAO/NSIAD-00-68. Washington, D.C.: March 14, 2000.
Defense Acquisitions: Progress in Meeting F-22 Cost and Schedule Goals.  GAO/T-NSIAD-00-58. Washington, D.C.: December 7, 1999.
Fiscal Year 2000 Budget: DOD’s Production and RDT&E Programs.  GAO/NSIAD-99-233R. Washington, D.C.: September 23, 1999.
Budget Issues: Budgetary Implications of Selected GAO Work for  Fiscal Year 2000. GAO/OCG-99-26. Washington, D.C.: April 16, 1999.
Defense Acquisitions: Progress of the F-22 and F/A-18E/F Engineering  and Manufacturing Development Programs. GAO/T-NSIAD-99-113.  Washington, D.C.: March 17, 1999.
F-22 Aircraft: Issues in Achieving Engineering and Manufacturing  Development Goals. GAO/NSIAD-99-55. Washington, D.C.: March 15, 1999.
F-22 Aircraft: Progress of the Engineering and Manufacturing  Development Program. GAO/T-NSIAD-98-137. Washington, D.C.:  March 25, 1998.
F-22 Aircraft: Progress in Achieving Engineering and Manufacturing  Development Goals. GAO/NSIAD-98-67. Washington, D.C.: March 10, 1998.
Tactical Aircraft: Restructuring of the Air Force F-22 Fighter Program.  GAO/NSIAD-97-156. Washington, D.C.: June 4, 1997.
Defense Aircraft Investments: Major Program Commitments Based on  Optimistic Budget Projections. GAO/T-NSIAD-97-103. Washington, D.C.:  March 5, 1997.
F-22 Restructuring. GAO/NSIAD-97-100BR. Washington, D.C.:  February 28, 1997.
Tactical Aircraft: Concurrency in Development and Production of  F-22 Aircraft Should Be Reduced. GAO/NSIAD-95-59. Washington, D.C.:  April 19, 1995.
Tactical Aircraft: F-15 Replacement Issues. GAO/T-NSIAD-94-176.  Washington, D.C.: May 5, 1994.
Tactical Aircraft: F-15 Replacement Is Premature as Currently Planned.  GAO/NSIAD-94-118. Washington, D.C.: March 25, 1994.