Investigators fault pilot’s early `feathering’ system activation for Virgin Galactic crash
05 Nov 2014
Federal accident investigators have worked out some leads into what went wrong with an experimental spaceship designed to ferry space tourists broke apart during a test flight, AP reported. However, they are still not able to explain why the craft prematurely shifted its shape prior to the deadly crash. (See: Virgin Galactic space craft crashes in California, killing pilot during test flight)
Another question that becomes moot with the crash is: How much would the accident push back the day when space tourism becomes a reality?
National Transportation Safety Board investigators were at work on Monday at the main wreckage area where Virgin Galactic's SpaceShipTwo fell to the ground in the Mojave Desert, but also collected tiny debris 35 miles away. The co-pilot died in the crash while the injured pilot parachuted out of the ship on Friday.
According to acting NTSB chairman Christopher Hart, cockpit video and data showed that the co-pilot unlocked SpaceShipTwo's unique "feathering" system earlier than planned. The system works on lines of the wing flaps used on airplanes to slow for landing - except that SpaceShipTwo's twin tails rotate up at a far more extreme angle, to a position that creates strong resistance and slows the descent.
However, while the co-pilot unlocked the system before planned, it should not have caused the craft to change its configuration, according to experts.
Commentators say the key to unlocking the mystery might lie in the answer to the question as to why a seasoned test pilot would prematurely unlock the craft's moveable tail section, triggering a chain of events that led to destruction of the ship and his death.
The ship broke up 50,000 feet above the Mojave Desert, 95 miles north of Los Angeles, moments following its separation from the special jet aircraft that carried the spacecraft for its high-altitude launch, Reuters reported.
The pilot, Pete Siebold, 43, who suffered a shoulder injury survived the crash, parachuted to the ground, but the co-pilot, Mike Alsbury, 39, was killed.
According to NTSB officials, it was Alsbury, flying for the ninth time aboard SpaceShipTwo, who unlocked the tail section, designed to pivot upward during atmospheric re-entry to ease descent of the craft.
Alsbury was supposed to wait until the ship was traveling at 1.4 times the speed of sound, fast enough for aerodynamic forces to hold the tail in place until time to actually move it into descent position, the report said quoting sources familiar with the spacecraft's operation.
For reasons not known, he released the locking mechanism about 9 seconds into a planned 20-second firing of the space plane's rocket engine, while the ship was moving at about Mach 1, the speed of sound, the sources said.
