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66 HYPERSONIC TECHNOLOGY FOR MILITARY APPLICATION areas, it should be noted that many of the facilities are 20 to 40 years old and do not have flow condi- tions of sufficiently good quality for aerodynamic and chemical kin- etic testing and code validation. 4) Facility development and construc- tion require a five to 10 year period and new facilities are not therefore likely to contribute substantially to design definition of the NASP research vehicle. Facilities for structural testing at 1200 C and above do not exist. Details of the upper atmosphere, including its local composition and flow turbulence are not sufficiently well-known to adequately establish the relation of flight conditions to results from ground test facilities. 7) Hypersonics requires a substantial and continuing investment in the development of new facilities and instrumentation. 8) In the Mach number range of 5 to 10, the knowledge and technology for facility construction exist; however, we have not developed the facilities to generate the required data base. 9) At Mach number 10 and above, no one facility today can fully sim- ulate all hypersonic flight para- meters. 10) Continued research is needed to explore the possibilities of develop- ing such a facility for aerodynamic and propulsion testing and CFD validation. 1 1 ) In the absence of full simulation, limited simulation testing should be done where possible for CFD valid- ation.

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HYPERSONIC TECHNOLOGY FOR MILITARY APPLICATION APPENDIX A: Statement of Task 67 With the current interest in and potential for hypersonic flight, there is a need to determine for the Air Force and for the nation the research and development approaches required to realize the opportunities offered by flight in this regime. In its report, National Aeronautical R&D Goals, March 1985, the Aeronautical Policy Review committee of the OSTP enunciated a transatmospherics goal as, "exploiting the growing convergence of aeronautics and space technology." It states that "the capability to routinely cruise and maneuver into and out of the atmosphere, to gain rapid responsiveness for low earth orbit missions (manned or unmanned), or to attain very rapid transport services between earth destinations from conventional runways, must be viewed as aerospace options with global importance for the future." The National Aerospace Plane program has been established to build a single stage research vehicle that can take off from a runway, achieve orbit, and return. A joint program among DARPA, Air Force, SDIO, Navy, and NASA, with planned total funding of $3.1B, NASP is in an accelerated technology development phase (II), which leads to a phase III technical readiness assessment in late 1989. If the assessment is positive, the program will proceed to design, fabrication, and test of a flight research vehicle in the 1990-1995 period. Against this background, the task of the AFSB committee on hypersonic technology is to: determine possible military uses of hypersonic flight draw on the developing hypersonic technology base, including the evolving results of NASP Phase II, to assess the technical feasibility of meeting the potential applications. identify the technological needs for hypersonic flight. assess the research and development support requirements including availability of expertise, data bases, and test facilities. provide technical advice to the command level on the research and development strategy of the NASP, including: 0 the level of technical risk in a single-stage to orbit research vehicle, and strategies for risk reduction 0 the research vehicle program approach to maximize the acquisition of knowledge in the most critical technical areas.