HI-TECH engineers say they have made the final breakthrough in the design of an engine that could power a passenger plane through space to Sydney in under four hours.

The team at Reaction Engines, based at Culham, have been working on the Sabre engine for almost 40 years in a bid to allow an aircraft to travel through space.

Now, a key component which pre-cools air streaming into the engine from 1,000C to -150C in less than 1,000th of a second has been successfully tested.

Business development manager Ben Gallagher said: “It is a phenomenally powerful piece of kit. We have tested it and shown it can work to the European Space Agency.” The ESA has already validated the viability of the Sabre engine and now the cooling system has been perfected, work can carry on to see it fully developed in the next three years.

Two projects have been outlined. The first is a plane known as Lapcat which will take off from an ordinary runway before reaching speeds of more than 3,800 miles an hour — five times the speed of sound — in the upper atmosphere.

The second is to use the engine in place of single use rockets on a space craft which would be reusable, cutting the cost of space expeditions dramatically.

Alan Bond, who founded Reaction Engines in 1989, said: “Sabre will enable an aircraft to fly anywhere in the world in under four hours or a spaceplane to fly into orbit around the Earth – slashing the cost of space travel and creating new commercial opportunities in space. This breakthrough puts the UK aerospace industry in pole position.”

Science Minister David Willetts added: “The engine is a potential game-changer in terms of space technology.”