Here’s What Caused a Catastrophic Virgin Galactic Crash

Investigators say space plane didn’t have enough safeguards

The Virgin Galactic SpaceShip2 (VSS Enterprise) glides toward Earth on its first test flight after being released from its WhiteKnight2 (VMS Eve) mothership over Mojave, California October 10, 2010. The craft was piloted by engineer and test pilot Pete Siebold from Scaled Composites. HO/Reuters/Corbis

Last year, a tragic crash killed two pilots and caused Virgin Galactic’s SpaceShipTwo to disintegrate. Now, the National Transportation Safety Bureau has determined the cause of the crash — a co-pilot’s error. During a hearing, investigators confirmed early findings that the space plane’s wings shifted as it re-entered the Earth’s atmosphere, causing a catastrophic failure.

SpaceShipTwo was never meant to make it to the moon, but to give tourists a glimpse at the edge of the atmosphere. The space plane was designed to be carried into the sky above a larger aircraft before being dropped and activating its rockets. At the highest point of the flight, the ship’s wings would rotate upward in a maneuver called “feathering” in order to create drag and let the ship slow down before floating back to Earth. However, NTSB investigators found that Alsbury unlocked the feathering system too early. The result was deadly.

In order for the feathering system to work, the co-pilot must first unlock the wings by pulling a lever, writes Loren Grush for The Verge. Both the pilot and co-pilot then have to pull two additional levers to start up the motor that feathers the wings. When Alsbury unlocked the wings, pressure from the plane’s transonic speeds and inertia overloaded the motors, according to the NTSB report.

The investigators strongly criticized Scaled Composites, the company that built SpaceShipTwo, for overlooking this major safety flaw in the designs. The report also found fault with the Federal Aviation Administration for failing to make sure the company fixed systems it found to be hazardous before the test flight.

“Manned commercial spaceflight is a new frontier, with many unknown risks and hazards,” NTSB Chairman Christopher A. Hart said in a press release. “For commercial spaceflight to successfully mature, we must meticulously seek out and mitigate known hazards, as a prerequisite to identifying and mitigating new hazards.”

Virgin Galactic is building a second SpaceShipTwo with an automatic system that will prevent the wings from unlocking early, according to a statement. They hope to resume testing in coming months.

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