Graham Warwick/ATLANTA

THE US AIR FORCE is seeking approval for a scaled-down hypersonic-technology research programme which will focus on hydrocarbon-fuelled supersonic-combustion ramjets (scramjets) for Mach 4-8 missiles.

The HyTECH programme would be an effort to continue US hypersonic research after the cancellation of the X-30 National AeroSpace Plane.

The plea comes after the USAF's decision not to fund the NASA/USAF HySTP scramjet flight-demonstration project.

Instead of the five-year, $400 million HySTP programme, NASA and the USAF now plan to pursue separate, $20 million-a-year hypersonic-research projects.

Dr Keith Ridley, director of the Air Force Wright Laboratory's Flight Dynamics Directorate, said that "...HySTP was too expensive for USAF needs". Speaking at the American Institute of Aeronautics and Astronautics' sixth international aerospaceplanes and hypersonic technology conference in Chattanooga, Tennessee, on 3-7 April, he added that USAF has decided to focus its efforts on Mach 4-8 missiles after reviewing the range of possible applications.

Work will continue with NASA on the High Mach Turbine Engine, a combined-cycle air turbo ramjet (ATR) for M0-5 aircraft, and on hydrogen-fuelled scramjets for M8-12 vehicles, Ridley said.

The $20 million-a-year HyTECH research programme is scheduled to begin in June. The plans call for a scramjet demonstrator to be fabricated in 1997, leading to M8 ground tests in 1998. Ground tests of the ATR are planned for 2000.

Flight demonstrations of the scramjet and ATR are scheduled for 2001, but will require an increased budget, he says.

Source: Flight International