That's when Feeney hits the switch. In an instant, he and his drifting crew are thrown back into their seats as the rocket engines fire and the ship blasts to four times the speed of sound till it reaches 34 miles (55 kilometers). Then the engines shut off, and the momentum allows the craft to coast to 71 miles (115 kilometers)the top of the trajectorybefore it slows to a halt and begins its free fall to Earth.
After a slow two-hour ascent under the balloon, the rocket portion of the trip lasts just a brisk 30 minutesabout seven minutes from the point the engines fire until the parachutes kick in on the return trip. From there it is a 20-minute parachute ride to the ground.
Winning the X-Prize?
The advantage in launching from this altitude is that the rocket doesn't suffer the same aerodynamic stress as during a ground launch. Rockets have been successfully launched from aircraft before. "A balloon is even easier because there isn't much movement," Feeney said.
"The X-Prize is basically an altitude prize," said Mark Lewis, professor of aerospace engineering at the University of Maryland in College Park, who specializes in advanced launch vehicles, "with the balloon and rocket combination the da Vinci team could certainly win the X-Prize."
But winning with this combination would be more of a demonstration, said Lewis, because this is not something that would likely evolve into a reusable launch vehicle. "It is not the obvious solution if you want to go commercial."
"There are some very clever designs and technology entered in the competition, and there are some very capable and credible teams," said Lewis.
The da Vinci team's first move was to build a prototype. But the material for the ribs of the aeroshell was expensive and hard to handle. Then the design changed. Now, with a better design, but considerably less cash, the Canadians are embracing a local product they had previously overlooked: wood.
The da Vinci engineers use the wood for the streamlined aeroshell that sits on a metal frame that in turn cradles the engine. Wood is not so far-fetched: oak has been used for heat shields of spacecrafts.
It once took an army of engineers with slide rules to build a space rocket. Now, with powerful computers on every desktop, a warehouse of enthusiasts can move into what was once a government monopoly. The da Vinci project, and the 23 others teams spawned by the X-Prize, embark in the spirit of the Wright Brothers. They launched a new era of flight by taking wing in an untried craft that also used wood.
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