GUY NORRIS / CLEVELAND
Proposed programme with NASA and Pratt & Whitney may use demonstrator for quick reaction hypersonic missile
The US Department of Defense, NASA and Pratt & Whitney may develop a dedicated supersonic combustion ramjet (scramjet) for the single-engined hypersonic demonstrator (SED), and may use the vehicle as the basis for a quick reaction hypersonic missile.
The SED is planned to use a follow-on version to the successfully tested hypersonic ground demonstration engine. The engine - GDE-2 - is aimed at the three-engined, Mach 7 X-43C demonstrator with a variable inlet. The SED, derived from the former Affordable Rapid Response Missile Demonstrator wave-rider project and revived as an engine testbed, will use a simpler fixed-inlet version of the GDE-2, which may be dubbed the Demonstrator test engine.
The final configuration of the GDE-2 is still being decided and is not expected to be frozen until year-end. This will allow time for design enhancements, enabling a possible revision of the engine's design top speed from M8 to M7.
Some members of the USAF's HyTech scramjet programme feel it would be better to redefine GDE-2's speed range closer to the upper end of the ongoing Revolutionary Turbine Accelerator turbine-based combined cycle project. This is being studied as the first element of an access to space concept under NASA's Next Generation Launch Technology initiative.
Although access to space remains a fundamental force behind the scramjet effort, the USAF's HyTech programme faces funding issues, as does NASA's X-43C. NASA remains confident the X-43C will go ahead, but there is concern the programme could be axed if the second X-43A hypersonic test attempt - scheduled for October or November - fails. The SED and X-43C are due to fly in 2006 and 2007 respectively.
Source: Flight International
