New world speed record

2004-03-28 15:52

London - The world speed record has been smashed in the United States.

An experimental, pilotless Nasa plane reached almost 8 000km/h - seven times the speed of sound.

The plane used a new hi-tech engine that could one day revolutionise air travel - cutting the flight time from London to Sydney to just over two hours, Sky News reports.

The hypersonic X-43A reached a speed of 7&648km/h using an air-breathing jet engine called a supersonic-combustion ramjet, or scramjet.

It was the second time Nasa scientists had attempted the feat. The first test flight ended in an explosion three years ago.

Nasa built the 4m aircraft under a $250m programme aimed at developing planes capable of flying around the world in a few hours.

They have investigated scramjet technology because it could cut the cost of rocket-speed travel.

Rockets must carry their own oxygen to combust the fuel they carry, increasing the weight they lift during launch, while scramjets take oxygen out of the atmosphere.

A modified B-52 bomber carried the X-43A and a rocket engine from Edwards Air Force Base to an altitude of about 13 300m.

Both were then dropped over the Pacific, where the rocket ignited and boosted the 1 260kg X-43A to over 33 333m before releasing it. The first X-43A flight ended in failure June 2, 2001, when the modified Pegasus rocket used to accelerate the plane veered off course and had to be destroyed.

The earliest such a plane could be in operation is 2025.

- News24