Virgin Galactic will update progress on flight tests of its SpaceShipTwo (SS2) at the Farnborough air show next week where, for the first time, it will also be displaying a full-scale replica of the sub-orbital vehicle. Scaled Composites, the developer of both SS2 and the WhiteKnightTwo ‘mothership’ which carries the spaceship to launch altitude, meanwhile resumed glide tests of SS2 at Mojave, Calif on June 26.
The mods were mainly focused on the redesign of strakes on the inboard of the SS2 vertical tails. Although a deceptively minor-looking alteration from two separate strakes per side to one larger one, the change is important for countering a tail stall condition uncovered during tests last September. Scaled says the stall event, from which the crew recovered successfully by using the vehicle’s unique feathering device, was at a specific condition which the operational SS2 will not encounter. However, just like a commercial aircraft, the SS2 will be a certificated passenger-carrying vehicle which will be passed safe to enter service only after the flight envelope has been fully explored.
Although no clear images of the revised ‘mega-strake’ have emerged, here are a few images showing the evolution of the tail since 2010.
Initial glide flight – single strake. October 2010 (Mark Greenberg/Virgin Galactic)
Static display – twin strakes February 2011 (Guy Norris)
Resumption of glide flights – single 'mega-strake' June 2012 (Virgin Galactic)