Aviation history was made on Saturday when NASA successfully launched an experimental jet that reached seven times the speed of sound, or about 8,000 km per hour.

The X-43A and its modified Pegasus booster rocket left the runway at Edwards Air Force Base, California, attached to the belly of a modified B-52 bomber.

The unpiloted 12-foot-long plane was dropped from the wing of the B-52B, boosted to nearly 100,000 feet by the rocket, and released over the Pacific Ocean where it flew on its own at Mach 7.

It was the first time that a non-rocket, air-breathing scramjet engine had powered a vehicle in flight at hypersonic speed.

An SR-71 'Blackbird' spy place, which flew at March 3.2, had established the previous world speed record.

The scramjet -- supersonic combustion ramjet -- is being tested in a $230 million programme to develop technology for possible use in future space launch vehicles and for military and civilian purposes.