Scramjet success as engine hits Mach 7.6

A jet engine which uses oxygen in the atmosphere to ignite hydrogen fuel has reached 7.6 times the speed of sound.

The air-breathing "scramjet" engine, which could eventually dramatically cut longhaul flight times, reached supersonic speeds for the first time during a test over the central Australian desert.

Engineers from the University of Queensland say any commercial application is years off but the successful test of the HyShot scramjet, which is capable of more than 3,100mph, at least proves the technology is viable.

The team fired the engine into the sky on the back of a rocket, which took it into the upper atmosphere. The engine kicked into action on the way back down at 22 miles above the earth, with data transmitted by radio until it began to burn up.

A dream of aviation researchers for decades, scramjets could one day cut flights from London to Sydney to only two hours compared with more than 20 now. But their first commercial application is more likely to be in satellite launching.