I think people haven't even thought about how to use this technology yet

Joel Spitz Nasa project manager

By contrast, a jet fighter plane travels at speeds of Mach 1 to Mach 2, and the Space Shuttle blasts into space at Mach 25.

The unmanned plane will be launched from Edwards Air Force Base in California and will fly for only about 10 seconds before it crashes into the Pacific Ocean.

"People have worked their whole careers to see this flight," said Joel Spitz, the X-43A project manager at NASA's Dryden Flight Research Center.

"We're making aviation history."

The X-43A, or "Hyper-X" was built specifically to test scramjets, or supersonic ramjets, which burn fuel in air travelling at supersonic speeds. A ramjet uses air at subsonic speeds.

The plane uses an air-breathing engine, drawing in oxygen from the atmosphere as it flies, and eliminating the need for heavy, expensive, liquid oxygen tanks. The oxygen combines with hydrogen for combustion.

Currently, the fastest air-breathing aircraft is the SR-71, which accelerates to slightly over Mach 3.

The X-43A may be fast, but at this early stage, it needs a push to get going. To be sure it reaches the necessary speeds, the X-43A will be attached to a booster rocket and ride piggy back on a B-52 to 24,000 feet.

The test plane will be carried aloft by a B-52 bomber

Once over the Pacific Ocean, the B-52 will drop the rocket, which will then ignite and accelerate to Mach 7.

The rocket and X-43 will separate, and the X-43A will enjoy a brief solo flight while engineers run manoeuvres, and test the plane's air-breathing engine.

Dr Spitz sees unlimited potential with the scramjet.

"We went from Kitty Hawk to the Moon in 70 years. I think people haven't even thought about how to use this technology yet."

He suggested that the air-breathing scramjet could revolutionise space travel, by making passenger and cargo flights into space affordable and practical.