Breaking News: Trailblazing Private Spaceship is Airborne

The flight plan for SpaceShipOne. CREDIT: Scaled Composites, LLC

MOJAVE, CALIFORNIA - A privately built and financed rocketship departed here today, headed for the first run at back-to-back flights to win the $10 million Ansari X Prize.

"Woohoo!" said Erik Lindbergh, grandson of famous flyer Charles Lindbergh, while SpaceShipOne soared overhead still attached to its White Knight carrier plane. Erik Lindbergh is on the board of the X Prize.

The $10 million X Prize goes to the first privately built vehicle that can haul a pilot and two passengers to the edge of space, then repeat the feat within two weeks.

SpaceShipOne is under the controls of a single pilot, but is weighted as if three people were aboard. For the record setting pair of flights, the vehicle will be boosted by a larger, stronger engine than that used for its last piloted flight on June 21.

If today's flight is successful, SpaceShipOne must then repeat the feat by Oct. 13.

Slung underneath the White Knight carrier aircraft, SpaceShipOne and its pilot, Mike Melvill, headed down the runway and lifted off to the cheers of thousands of gathered well-wishers. In attendance were film directors John Landis and James Cameron, as well as entrepreneur Elon Musk, astronaut William Readdy, and NASA chief Sean O'Keefe.

The joined vehicles will now begin a slow spiraling ascent high above the desert landscape. When all is ready for the push to space, the White Knight will release SpaceShipOne. The vehicle will glide free for a few seconds before Melvill ignites the vehicle's hybrid rocket motor.

SpaceShipOne's target in the sky is 62.5 miles (100 kilometers) altitude - a sky-high goal required by the X Prize Foundation of St. Louis, Missouri in order to vie for the cash prize. The altitude is generally considered to be the threshold of space.

If the suborbital flight today is successful, SpaceShipOne's design team, Scaled Composites based here at the Mojave Spaceport, are ready to turn the vehicle around for reflight - perhaps making the second rocket run five days later on Oct. 4.

After reaching altitude, the SpaceShipOne will glide back to the Mojave Spaceport.

Whether or not the vehicle "made the grade" so to speak, will be verified by independent methods, said X Prize Foundation head, Peter Diamandis, in a pre-flight interview with SPACE.com.

At least three independent methods, two radar tracking systems, and an onboard "gold box" will be utilized to verify flight conditions of SpaceShipOne as it makes its suborbital trek, Diamandis said.

More than a dozen teams around the globe are building, testing, and flying hardware to compete for the Ansari X Prize, an offer that expires at year's end. The X Prize Foundation hopes to jump-start the space tourism industry through competition among entrepreneurs and rocket experts.

-- SPACE.com's Anthony Duignan-Cabrera and Robert Roy Britt contributed to this report.

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