Aerojet has been awarded a $43 million contract from Boeing Phantom Works to develop the ‘HyFly’ dual combustion ramjet test flight engines for the Defence Advanced Research Projects Agency and Office of Naval Research’s HyFly hypersonic long-range strike missile demonstrator.
The objective of the HyFly program is to demonstrate the hypersonic propulsion and vehicle characteristics of a solid motor boosted hypersonic long-range strike missile demonstrator, which, when fully developed will be capable of penetrating deeply buried targets.
‘In response to the events of last September, the nation is seeking weapons with the ability to strike fast and deep in enemy territory,’ said Joe Abbate, Aerojet executive director, defence systems. ‘The HyFly missile is an answer to this challenge.’
Aerojet’s HyFly engine will accelerate the demonstrator to Mach 6 cruise speed and provide the sustaining propulsion with liquid hydrocarbon fuel during hypersonic cruise, achieving a range of 600 nautical miles.
Aerojet will be required to develop 14 flight test engines – six for ground test and eight for flight evaluation. Currently Aerojet is engaged in Mach 6 testing of a heavy weight version of the HyFly engine at the NASA Langley Research Centre. The first flight of the dual combustion ramjet (DCR)-powered HyFly vehicle is scheduled for November 2004.
The HyFly DCR is said to build upon a concept established in the late 1970s. The DCR employs two air inlet systems. One system feeds a subsonic gas generator in which a fuel-rich gas is generated. The gas is then co-axially mixed with supersonic air from the second inlet system.
The DCR is a dual mode system; its diverging combustor section permits thermally choked operation as a ramjet, but allows for transition into a supersonic combustion ramjet also called a scramjet.