The co-pilot of Virgin Galactic’s SpaceShipTwo, which broke apart during flight Friday over California’s Mojave Desert, activated the aircraft’s re-entry system just seconds into its doomed test flight, investigators said Sunday.
The disaster killed co-pilot Mike Alsbury, 39, and seriously injured 43-year-old pilot Pete Siebold.
Alsbury pulled a lever only nine seconds into the flight that unlocked the aircraft’s pivoting tail section, Reuters reports. The “feathering” system, as it is referred to by engineers and experts, is designed to slow the craft down during flight back to Earth.
SpaceShipTwo was designed to take paying customers into space. According to the design, after being released from the “mothership,” WhiteKnight Two, the crew of SpaceShipTwo fires the plane’s rocket engine, accelerating the plane to 2,500 mph. After shutting down the rocket system, the plane coasts to 328,000 feet, just outside of Earth’s atmosphere. As the plane makes its turn back towards Earth, the crew members are supposed to activate the feathering system.
But Alsbury reportedly unlocked the system just after being released from WhiteKnight Two.
“The feathering occurred at the worst possible flight condition: Mach 1 and maximum dynamic pressure,” Princeton University’s Robert Stengel said in an email to NBC News. “The craft was never structurally designed to withstand such a condition. Had the feathering occurred 10 or 20 seconds later, there probably would not have been a problem.”
Stengel is not directly involved with the Virgin Galactic project but uses the aerodynamics of SpaceShipOne as a teaching tool in his flight dynamics classes at the university.
It is unclear why Alsbury initiated what investigators called an “uncommanded feather.” Christopher A. Hart, acting chairman of the National Transportation Safety Board, said he is not yet sure that Alsbury’s actions are even the cause of the disaster.
“There’s much more that we don’t know,” he said Sunday, according to The Washington Post. “I’m not saying this was the cause.”
A so-called human factors expert is said to have joined the investigation Monday.
Virgin Galactic’s billionaire owner, Richard Branson, travelled to California on news of the crash. He promised to work with investigators to determine the cause of the accident and said he still believes his vision of space flight for paying customers can become a reality.
Photo Source: Virgin.com, Associated Press