‘Scramjet’ Speed of Mach 7.6 Reported

Australian researchers said an air-breathing “scramjet” engine had successfully achieved supersonic ignition in the atmosphere for the first time, reaching 7.6 times the speed of sound.

Project leader Allan Paull said data analyzed from the July 30 test showed the engine, which uses oxygen in the atmosphere to ignite hydrogen fuel, had reached Mach 7.6--a speed that would allow travel from London to Sydney in two hours instead of more than 20.

The test over the central Australian desert marked the first time engineers made the supersonic engine work outside an air tunnel.

Engineers say any commercial application is still years away.