"Supersonic flight is when you break the speed of sound, and achieve speeds over Mach 1 [1235km/h]," says Professor Michael Smart from the Centre for Hypersonics at The University of Queensland. "Hypersonic flight starts at Mach 5."
Mach 5 is about 6170km/h, but the UQ team has already tested a scramjet at Mach 7.5, or 9260km/h. The team – which shares technology with NASA and was previously in the HIFiRE hypersonics project with the US and Australian governments – has made a total of seven test flights, at Woomera, SA, and in Norway, with three Australian-made scramjets.
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