SpaceShipOne Flies Again

by Dr. Richard Stimson

in Others

On Wednesday September 29th SpaceShipOne successfully flew again in the pursuit of the X Prize competition worth $10 million. One more successful flight and they will have won it.

Here is the criteria for the winning the prize: the winning team must privately finance, build and launch a spacecraft that can carry three people 62 miles above the Earth’s surface, return safely to Earth, and then do it again within two weeks. Some 26 teams from seven countries are vying for the prize. The 62-mile threshold is generally accepted as the point where the Earth’s atmosphere ends and space begins.

The SpaceShipOne team is planning on completing the second flight requirement on Monday October 4th, although they have until October 13 at 0834 to make the attempt.

On Sept. 29 at 0712 the SpaceShipOne rocket ship attached to the White Knight, the carrier airplane, left the Mojave, California runway before thousands of spectators. The White Knight with its payload climbed to about an altitude of 48,000 feet where SpaceShipOne detached from the White Knight and its rockets fired, sending SpaceShipOne roaring straight up for about 2 minutes. Its bright streak toward space could be seen from the ground.

Before reaching apogee the pilot, Mike Melvill, experienced some nervous moments as the spacecraft began to spin unexpectedly as it sped through space at nearly three times the speed of sound. Melvill said later that he figures there were at least 20 turns, with some of them at a high rate producing a corkscrew like flight path. “I’m not sure what kicked it off,” he said. “It was probably something I did.”

Rutan, the designer of the craft, didn’t think it was pilot error. Instead he suggested it was the result of the “dihedral effect” in which air buffeting the spacecraft at an angle causes it to roll.

The spin caused the worried flight controllers on the ground to advise Melvill to abort his ascent, but Melvill was close to the goal of at least 62 miles altitude and kept going a few more seconds before shutting down the engine eleven seconds earlier than planned.

He achieved 64 miles (337,500 feet). After landing at 0833 without further incident he said, “I did a victory roll at the top.” “You just cannot describe what a feeling this is. Maybe I’m crazy.”

The first test flight last June 21st also had control problems. In this instance, the craft unexpectedly rolled to the left and then to the right and developed trim problems as the craft experienced horizontal wind shear. That problem was fixed and a new engine was designed to provide 20% greater thrust.

Experiencing control problems with experimental craft is not new. The Wright brothers had their own problems with controlling the Flyer.

An interesting aspect of the flight is that employees of Burt Rutan’s company, Scaled Composites, contributed personal items to simulate the weight of two additional passengers to provide the 400 pounds required under the X Prize rules. All items were carefully weighed and sealed in boxes. The items included tools, toys, pictures of children, a prized watch and the ashes of Rutan’s deceased mother.

The X Prize is spurring private space flight. Just recently Sir Richard Branson, the founder of Virgin Airways, announced the formation of a new company, Virgin Galactic, for the purpose of offering space jaunts in 2007. He plans to license the technology from Mojave Aerospace Ventures, a company founded by Rutan and Paul Allen, the billionaire cofounder of Microsoft and investor in the SpaceShipOne venture.

Tickets will cost about $208,000 for a 2-hour flight. They expect to fly 3,000 new astronauts in the first 5 years. Only a few civilians have flown into space and they paid much larger sums of money to ride on ships operated by the Russian government.

The biggest hurtle to space tourism may be legal and regulatory rather than technical. The House passed a bill earlier this year creating a licensing system. A similar bill is languishing in the Senate. A bill may not pass this year.

Melvill is scheduled to speak at the EAA AirVenture in Oshkosh on December 17th at a program observing the anniversary of the Wright brothers’ first flight.

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