MOJAVE, Calif. -- Ignoring a warning to abort the flight, a test pilot took a stubby-looking rocket plane on a corkscrewing, white-knuckle ride past the edge of the atmosphere Wednesday, completing the first stage of a quest to win a $10 million prize.
As spectators and controllers nervously watched from the ground, SpaceShipOne rolled dozens of times as it hurtled toward space at nearly three times the speed of sound. It reached an altitude of 64 miles over the Mojave Desert.
SpaceShipOne, with pilot Michael Melvill at the controls, made history in June when it became the first private, manned craft to reach space.
Spaceship designer Burt Rutan said he asked Melvill to shut down the engine, but Melvill kept going until he reached the altitude specified under the rules for the Ansari X Prize.
"I did a victory roll at the top," Melvill joked from atop the spaceship after it glided safely to a landing.
The Ansari X Prize will go to the first craft to safely complete two flights to an altitude of 328,000 feet, or 62 miles -- generally considered to be the point where the Earth's atmosphere ends and space begins -- in a 14-day span.
The St. Louis-based X Prize Foundation is offering the bounty in hopes of inspiring an era of space tourism in which spaceflight is not just the domain of government agencies such as NASA.
The problem was being analyzed by the spacecraft's builders, who must decide whether to proceed with another flight Monday in order to win the X Prize.
But Rutan and Melvill were confident the flight would go on as planned. Rutan said rolling occurred during flight simulations, and it was not a complete surprise when it happened on Wednesday.
"I've looked at it, and I think we just change out the engine and fill it with gas and let it go," Melvill said.
The test pilot said he may have caused the rolling himself.
"You know, you're extremely busy at that point," he said. "Your feet and your hands and your eyes and everything is working about as fast as you can work them, and probably I stepped on something too quickly and caused the roll."
Rutan, with more than $20 million from Microsoft billionaire Paul Allen, secretly developed SpaceShipOne and is well ahead of two dozen teams building X Prize contenders around the world.
During its 81-minute flight, SpaceShipOne climbed to 337,500 feet -- nearly 10,000 feet above its target, said Gregg Maryniak, executive director of the X Prize Foundation. The craft made more than two dozen unexpected rolls as the fat fuselage and spindly white wings shot skyward.
Rutan said controllers asked Melvill to shut the engine down early because of the rolling, but Melvill kept going until he was certain he would reach the target altitude.
"We actually were asking him to go ahead and abort, to shut it off to where he wouldn't have gone the [62 miles]. He stayed in there just for a handful of seconds more," Rutan said.
Melvill said he did shut down the engine 11 seconds earlier than planned after determining the craft would reach its target.
The mission began when a specially designed jet with the ship under its belly took off from the desert north of Los Angeles. At 47,000 feet, SpaceShipOne was released, and Melvill fired its rocket motor and pointed the nose toward space.
A crowd of VIPs watched from below the airport control tower. The mission was televised live.
The Ansari X Prize was modeled on the $25,000 prize that Charles Lindbergh won in his Spirit of St. Louis for the first solo New York-to-Paris flight across the Atlantic in 1927.
Already, the ultimate goal of the X Prize appears in sight: Richard Branson, the British airline mogul and adventurer, announced Monday that beginning in 2007, he will begin offering paying customers flights into space aboard rockets like the SpaceShipOne. He plans to call the service Virgin Galactic.
Among those watching Wednesday's flight was Adam Smith, 14, of Vienna, Va., who has earned $1,000 this summer toward a down payment to a company called Space Adventures, which is taking reservations for space travel someday.
Smith said he has been interested in space "as far back as I can remember."
"It was just one of those things -- I want to do this," the ninth-grader said.