Pilot actions examined in U.S. crash of Virgin Galactic spacecraft

Sheriffs' deputies look at wreckage from the crash of Virgin Galactic's SpaceShipTwo near Cantil, California November 2, 2014. REUTERS/David McNew

MOJAVE Calif. (Reuters) - A human-factors expert will join the investigation of the fatal crash of Virgin Galactic's passenger spacecraft to study why the co-pilot prematurely unlocked a pivoting tail section of the ship during a test flight, a top safety official said on Monday.

The untimely engagement of the tail mechanism, designed to slow the vehicle's descent into the atmosphere from space, and the possibility that pilot error was to blame, were disclosed by the National Transportation Safety Board (NTSB) late on Sunday and have emerged as a main thrust of the inquiry into Friday's crash.