Australian Hypersonic Test Flight Reaches Mach 7.5

Fancy a flight at 9188km/h? That's exactly what the Hypersonic International Flight Research and Experimentation project has achieved with a test flight in Australia, demonstrating that scramjet technology can push the speed of a rocket up to Mach 7.5. Image: Australian Department of Defence

During the tests, HIFiRE -- a joint program between the US Department of Defence and Australian Defence Science and Technology Organisation -- reached an altitude of 278km. A similar launch took place in 2012, but that rocket only hit Mach 3 -- coming below the definition for hypersonic, which requires a body to travel at five times the speed of sound, at Mach 5.

The craft uses sounding rocket to get it off the ground, but then employs a scramjet to reach hypersonic speeds. The scramjet uses the speed of the vehicle to compress air for combustion within its engine, allowing the gas flow to remain supersonic the whole way through. It's hoped that these engines could be used to build super-fast jets of the future.

As The Express points out, a speed of Mach 7.5 would allow you to travel from London to Sydney in just two hours. But you might be in for a wait before that happens: Current test flights are still only investigating the real-life aerodynamics of the technology.