Richard Branson unveiled his Virgin Galactic spaceliner for tourists willing to pay 200,000 dollars a ticket Monday, showing off a white port-holed craft suspended under the wings of a mothership dubbed the White Knight.

Previewing the roll-out of the Virgin Galactic craft in California's Mojave desert, the British billionaire said he planned to be on its first passenger flight in about 18 months time with his family and the space ship's American designer Burt Rutan.

Behind him, SpaceShipTwo was suspended between what looked like two jet aircraft joined together with a common wing. Emblazoned on the White Knight mothership was the image of a young woman representing Branson's mother Eve diving through space.

In an interview with CNN before the test-flight, Branson explained how the craft was designed to return to Earth "like a giant shuttlecock" to avoid the buildup of heat that makes re-entry one of the great hazards of space travel.

"What happens is that the six potential astronauts will be sitting in the central pod here, what is their spacecraft, and the White Knight will take them up to about 60,000 feet.

"At 60,000 feet, they will drop away and they will then go 2,000 miles per hour in 10 seconds where they get propelled into space," he said.

Once in space, the travelers can get out of their seats and look back at the Earth through large portholes - the first in any space craft, he said.

"They can float around and become astronauts, and, when they are ready to come back into the earth's atmosphere again, they will put themselves back into their seats and buckle in and they will begin their voyage back into the Earth's atmosphere.

"At that stage the space ship effectively turns into a giant shuttlecock - that would be the genius of Burt Rutan, the engineer behind it," he said.

"And so it literally feathers its way back into the Earth's atmosphere so it doesn't have the enormous heat buildup that some of the NASA space ships have had in the past," he said.