Hyper-X: Flight Validation of Hypersonic Airbreathing Technology

Abstract This paper provides an overview of NASA’s focused hypersonic technology program, i.e. the Hyper-X program. This program is designed to move hypersonic, air breathing vehicle technology from the laboratory environment to the flight environment, the last stage preceding prototype development. This paper presents some history leading to the flight test program, research objectives, approach, schedule and status. Substantial experimental data base and concept validation have been completed. The program is concentrating on Mach 7 vehicle development, verification and vali- dation in preparation for wind tunnel testing in 1998 and flight testing in 1999. It is also concentrating on finalization of the Mach 5 and 10 vehicle designs. Detailed evaluation of the Mach 7 vehicle at the flight conditions is nearing completion, and will provide a data base for validation of design methods once flight test data are available. Introduction Airbreathing propulsion offers substantial advantages for hypersonic flight as illustrated in figure 1. It is an essential ingredient for sustained endoatmospheric hypersonic cruise applications such as “global reach” vehicles, and can significantly improve the perfor- mance of space launch vehicles. Airbreathing ramjetlscramjet (supersonic combustion ramjet) engines could improve mission effectiveness by reduc- ing on-board propellant load in favor of payload and by increasing operational flexibility. The fastest airbreathing engine-powered airplane, the SR-7 1, can cruise just above Mach 3, about 60% of the Mach