Hypersonic flight involves travelling at more than five times the speed of sound (Mach 5).
Scientists involved in the programme -- called Hypersonic International Flight Research Experimentation (HIFiRE) -- are developing an engine that can fly at Mach 7, Michael Smart of the University of Queensland told AFP.
"It's an exciting time... we want to be able to fly with a hypersonic engine at Mach 7," said Smart, a hypersonics expert involved in the programme which also includes US aerospace giant Boeing and German space agency DLR.
He added that the scramjet was a supersonic combustion engine that uses oxygen from the atmosphere for fuel, making it lighter and faster than fuel-carrying rockets.