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6 Recommendations This chapter sets forth the committee's recommendations. These recommendations are based on the findings in the preceding chapters and directed at the specific matters in the legislation that requested this study (see Statement of Task in Preface). The committee's principal recommendation, which appears immediately below, requires action by Congress. The numbered recommendations that follow require action by the DoD. Specific authorization and appropriation by Congress may be necessary to implement some of the numbered recommendations. DESIRABILITY OF WAIVER FOR THE F-22 TESTS Principal Recommendation. Permit a waiver of the foul-up, full-scale, live fire tests required by law for the F-22. The co~runittee believes that such tests are impractical and offer low benefits for the costs. Recommendation I. Interpret a waiver as reinforcing the need to conduct robust live fire tests of the F-22 that build incrementally from the component level to the subassembly or large assembly levels. (Recommendations to strengthen the current test program appear below.) COST-BENEFIT METHODOLOGY Recommendation 2. Continue DoD efforts to develop viable cost- benefit methodologies for planning the extent of live fire testing. Pursue methodologies to examine cost-benefit issues in the light of frameworks that take a broad view of how the future may develop for weapon systems like the F-22. 94

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Recommendations 95 SUFFICIENCY OF TESTS PLANNED FOR THE F-22 The following recommendation applies to the replication of anti-air missile warhead threats against the F-22. Recommendation 3. Consider, in fixture analyses and tests, the kill mechanism that involves dense multiple fragment impacts. Although the Air Force and its contractors have constructed a comprehensive live fire test program, the following specific actions are recommended to strengthen the program as the F-22 proceeds with EMD and initial production. Recommendation 4a. Conduct additional live fire testing to determine the damage that can be expected from a hit in the Frame 6 aft boom attachment area. Determine the most critical shot lines for this testing. Recommendation 4b. Expand analyses to predict damage sizes and residual strengths of the aft boom, Frame 6, and horizontal tail pivot shafts after being hit by 30mm HE] rounds. Also, determine the risk of aircraft loss should it be found that loss of a horizontal tad! is possible. Recommendation 4c. Conduct furler analysis of the aft fuel tank (A-~) prior to the conduct of Test 4D. Focus this analysis on determining the adequacy of the test specimen, with particular emphasis on its ability to simulate accurately the reaction of the entire tank. Recommendation 44. Make the operational community fully aware that a fuel ingestion risk to the aircraft exists at a fuel state higher than 60 percent. (This risk arises because the fuel tanks next to the engine inlets are not empty at fuel states above 60 percent, thus, a puncture could lead to fuel ingestion by art engine and potential engine failure.) Recommendation 4e. Conduct the tests and analyses, proposed by the F-22 SPO, on the flammability of coolant and other fluids and the attendant vulnerability of the aircraft. Recommendation 4f. Undertake the analysis and test, proposed by the SPO, of ablative materials in the weapons bay. Also, conduct further

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96 Live Fire Testing of the F-22 analysis of the tradeoffs associated with additional ordnance protection or defensive measures. Recommendation 4g. Fund the ITCG/AS arid the Joint Live Fire Test Program to assure the completeness of data on the vuInerabilities of on-board ordnance. Recommendation 4h. Fund the proposed Joint Live Fire testing of FIl9 engine components to alleviate the paucity of testing against those components. Recommendation 4i. Emphasize continuing efforts by the F-22 SPO and ITCG/AS to develop improved methodologies for reducing flight crew vulnerability. Recommendation 4j. Use the prototype air vehicle fuselage in Test 6A in lieu of a mock-up. (The Air Force has considered using this fuselage for Test 6A.) In addition, the committee recommends that the Air Force begin planning for expeditious vulnerability assessment testing of the F-22 similar to Mat being conducted or planned for variants of the Navy's Few. Recommendation Sa. Use large subassemblies from production- representative hardware (e.g., a damaged aircraft or other source) in these tests. Recommendation Sb. Provide these assets, as soon as they become available, to the vulnerability assessment community for the conduct of live fire tests. Recommendation 5c. Direct the tests at (a) verifying predictions from the current F-22 live fire test program and the models used, arid (b) testing the effects on overall F-22 vulnerability assessment brought about by configuration and mission changes. Also, use the tests to verify techniques for repairing battle damage to the F-22's new composite materials and systems.

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Recommendations OTHER RECOMMENDATIONS Vulnerability Requirements Recommendation 6. Reexamine expeditiously, for future F-22 missions (e.g., air-to-surface), the balance of requirements among susceptibility, vulnerability, and related performance parameters. Recommendation 7. Include in operational requirements for any ne missions user validation of quantitative vulnerability requirements, and plan new live fire tests as necessary in response to those requirements. Vulnerability Assessment Tools Recommendation X. Update and improve expeditiously the various standards, handbooks, and design guides that are important to the aircraft vulnerability community. Recommendation 9. Direct the ITCG/AS to define and plan a Joint Live Fire Test Program that wall, over the next several years, produce sourld vulnerability data bases; apply aggressive funding to implement this program. Recommendation lOa. Validate and accredit formally, by the ITCG/AS and the Joint Technical Coordinating Group on Munitions Effectiveness, the vulnerability assessment models used by the Air Force and other services. Recommendation fob. Improve the vulnerability models of the vulnerability community, and adopt these improvements for the F-22. Recommendation 10c. Explore the application of advanced methodologies currently being used by nuclear weapon designers and other industries. Recommendation 104. Focus on ways to understand fillly the response of F-22 composite materials to ballistic damage, and develop and exercise analysis tools that can handle large-scale damage effects. 97

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