Virgin Galactic's SpaceShipTwo mothership WhiteKnightTwo moved down a runway during a low speed taxi trial at Mojave air and spaceport on Friday 12 December at about 1500h local time.

Under its own power from its two inboard Pratt & Whitney Canada PW308A engines the four-engine experimental aircraft went to the end of Mojave spaceport's runway 30 turned around and went back to its designer Scaled Composites' hangar. Airport crash trucks had been positioned on either side of the runway, indicating an imminent taxi trial.

"A Scaled [Composites] truck with a videographer on top was following [WK2]," a Mojave spaceport source told Flightglobal.

The completion of taxi trials, a significant milestone for the twin hulled aircraft's development, would mean an impending first flight, which has been expected this month.

Following the roll out of WK2 on 28 July the mothership was expected to fly in September. Other Mojave sources report that after the taxi tests the first flight is scheduled for around the 19 December. Meteorological predictions for the next few days rule out any flights due to the possiblity of snow.

Its payload, SpaceShipTwo, should be unveiled in the first half of next year. Initially used for practicing carrier flights with its mothership, by the end of 2009 Virgin Galactic hopes WK2 will be air launching SS2 for the spacecraft's own glide back and rocket powered flight tests.

See a large still image of the taxi trial at Rob Coppinger's Hyperbola blog

Source: Flight International