"You can't even imagine my excitement," said Baxter after seeing the models. Baxter, a real estate marketing executive, said he recently completed preflight training that included being subjected to extreme g-forces in a whirling centrifuge. He hopes to be in space in a year.
"Yeah, I'm scared," he said. "But this is about realizing a childhood dream. Space travel is something I've been thinking about since I read Jules Verne as a kid."
The primary job for the designers will be confirming that the pair of experimental vehicles is safe.
The issue was highlighted last July, when the spacecraft's engine exploded during a routine ground test. Three people died in the accident, and California occupational safety inspectors fined Scaled Composites $25,870.
Investigators and the company's engineers say they are still trying to figure out exactly what went wrong.
"We don't know yet exactly what caused it," Rutan said. He added that there was "no question" that the accident is causing a delay in the engine's development, but did not comment on whether that would disrupt plans for test flights.
Rutan acknowledged that the project has risks, but said that when the spacecraft starts flying paying passengers, it will be at least as safe as the early airlines were in the 1920s.
That era was not a particularly safe time for air travel, by modern standards, but Rutan said it would be "hundreds of times safer" than government-funded space flight has been to date.
Branson said he has already reserved seats on one of the early flights for his elderly mother and father.
The pair and other Scaled Composites engineers attending Wednesday's news conference said they would keep many of the technical details of their launching system secret, but they offered a few facts about the craft.
White Knight Two will have about the same wingspan of a Boeing B-29 Superfortress, but, in contrast to the World War II bomber, both it and SpaceShipTwo are being built entirely from ultralight composite materials.
Virgin Galactic showed video of workers lifting big sections of the spacecraft with little effort, as if they were made of light plastic.
The spacecraft looks decidedly different from its predecessor, SpaceShipOne, which earned Rutan's team the $10-million-U.S. dollar Ansari X prize in 2004 by becoming the first privately built, manned rocket ship to fly into space twice in a span of two weeks.
SpaceShipOne was smaller, with just three seats, and a more science-fiction-like design.
Virgin Galactic's SpaceShipTwo is much larger and incorporates notable design changes, including the relocation of its wings from the top to the bottom of its fuselage.
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