An artist's conception shows a WhiteKnightTwo carrier plane in flight, with a suborbital SpaceShipTwo craft slung under its 140-foot (43-meter) wingspan.

After reaching an altitude of about 50,000 feet (15,240 meters), SpaceShipTwo will detach from the carrier craft and rocket skyward at more than three times the speed of sound until the passenger plane reaches the edge of space—about 65 miles (104 kilometers) above Earth.

WhiteKnightTwo's left fuselage contains a flight deck and cabin, while the right fuselage is configurable. The first working example of the carrier craft was unveiled July 28, 2008.

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