Speaking at the UK parliamentary science and technology committee's space policy review meeting in London last week, Virgin Galactic president Will Whitehorn said that NASA had budgeted to buy seats on SS2 flights for astronaut training after the first six months of commercial operations. He also expected NASA to conduct research flights where scientists would fly with their microgravity experiments.
Whitehorn said SS2 and its carrier aircraft White Knight 2 (WK2) could have up to 100 test flights between May 2008 and May 2009, when commercial services are due to start.
Meanwhile, Virgin Galactic has begun studying a SpaceShipFour (SS4) that could serve as a satellite launcher. By 2014 a version of WK2, with its 13,300kg (30,000lb) payload capability, could air launch the two-stage SS4 vehicle. SpaceShipThree would be an orbital version of SS2 (Flight International, 23-29 August 2005).
Source: Flight International