SpaceShipOne, which in June entered history as the first non-military space rocket, will stage its second sub-orbital flight in California's Mojave desert, in what its creators hailed as the start of a new space race.

The flight was scheduled to take place just two days after Burt Rutan and British tycoon Richard Branson announced a tie-up to start a "galactic" airline aimed at taking a huge step towards space tourism.

SpaceShipOne will seek to equal its June 21 feat when it touched the fringes of space, 100 kilometers (62 miles) up, before making what its creator Rutan admitted had been a scary return to base here.

But Rutan was upbeat about the prospects of Wednesday's flight of his stubby rocket plane, which -- if successful -- will take him and his US team half way to pocketing the 10 million-dollar Ansari X prize.

"We are all very confident that we can pull this off and turn it around very quickly," the 61-year-old pioneer told journalists late Tuesday, vowing to better the 62-mile or 328,000 foot sub-orbit SpaceShipOne achieved in June.

"I don't want to give myself that scare again," he said, explaining that the craft only just surpassed its 328,000-foot goal last flight around.

But, he warned, he and the Mojave Aerospace Ventures team were taking the first steps into a largely unexplored new era. "Anything can happen," he said, adding however that Wednesday's flight was not its riskiest by far.

A specially adapted jet, White Knight, will take SpaceShipOne up into the sky at 6:30 am (1330 GMT) and the space vessel will start its rocket engine at a height of 47,000 feet (15 kilometers) at around 7:50 am.

It should then enter the fringes space, leaving the as yet unidentified pilot weightless for around 3.5 minutes, and taking the craft to the second phase of its quest for the prize money, organisers said.

If the flight is a success, Rutan's spacecraft will make a new flight one week later on October 4 to qualify for the Ansari X Prize, which more than two dozen teams have set their eyes on.

The prize is offered by a private US-based foundation. The winner must send the same manned vessel into space twice in two weeks, carrying the pilot and the equivalent weight of two passengers.

Instead of lead weights, boxes of memorbilia and trinkets supplied by team members and sponsors -- who include major names such as candy maker M and M and soft drink 7UP -- will act as ballast, Rutan said.

The Ansari foundation launched the prize eight years ago to give the same impetus to space travel that the Orteig prize did to inspire Charles Lindbergh's first transatlantic flight in 1927.

Rutan, 61, and his company Scaled Composites joined with Microsoft founder Paul Allen and his firm Vulcan to form the Mojave Aerospace Ventures team, build SpaceShipOne and further the cause of private enterprise in space.

There are 26 teams in contention for the Ansari prize but SpaceShipOne believes it is the leader, according to Sarah Evans, a spokeswoman for the Ansari X Prize foundation in St Louis, Missouri.

"The other teams have not given notice that they will fly," she said.

A Canadian team, Da Vinci, which has linked up with the world's biggest online gambling website, goldenpalace.com, plans to launch a manned rocket attached to a balloon at 90,000 feet (27,000 metres). The return to Earth would be with the help of a parachute.

The Canadians had planned a trial run on October 2 but postponed it.

Rutan expects SpaceShipOne to attract a lot of investment to the sector, and that in "a few years" people will be able to buy tickets for suborbital flights.

Rutan sat by Branson's side in London on Monday when the British tycoon and adventurer, who founded Virgin Atlantic Airways, announced he had signed a 14 million pound (25 million dollar) accord with Mojave Aerospace Ventures to set up Virgin Galactic, the first company to offer trips into space for the general public.

The project will use technology based on SpaceShipOne and Branson has predicted the first flights could take place in three years.

Rutan was amazed by the interest that he said marked the start of the race for commercial space travel, adding that it was more than he could have dramed of. "We expected interest like this a couple of months after the X Prize, but it's happened already."

The Aviationweek magazine said in its latest edition that US businessman Robert Bigelow has offered a 50 million dollar prize for the building of a private launcher that can take five-to-seven astronauts into space by the end of the decade.

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