Elon Musk reveals cause of SpaceX explosion

City News Service | 7/21/2015, 11:59 a.m.
Elon Musk says SpaceX has pinned down what probably caused the company's rocket to explode minutes after liftoff.

Elon Musk says SpaceX has pinned down what probably caused the company's rocket to explode minutes after liftoff.

After reviewing data from the failed mission to the International Space Station, Musk says it looks like a two-foot-long metal bar called a strut failed

The strut was meant to hold down a helium tank in the rocket, and when it failed the tank crashed violently around the compartment, leaking gas, which caused an explosive drop in oxygen pressure.

Musk said the finding is only an "initial assessment" and investigations will continue, but that SpaceX is prepared to make changes.

The accident could have been prevented, Musk said on a press call Monday. The strut is a tiny part of the spaceship that was made by another company, and SpaceX didn't test it before launch.

Instead, the part was certified by a third party to withstand the enormous pressure of a rocket liftoff. Musk declined to name either the company that made the part or certified it, but he did say that SpaceX will switch to a different strut supplier and will do its own testing from now on.

SpaceX designed the Dragon spacecraft -- and the rocket, Falcon 9, that propels it -- from scratch and makes all of the major components in house.

But even the smallest weak link can cause disaster. Though the flight was unmanned, more than two tons of research equipment, provisions for the ISS crew and hardware for the space station were lost in the explosion.

Musk said that SpaceX hasn't launched a mission since the accident, and that as a result it's missed out on "hundreds of millions of dollars" in revenue. He said he doesn't expect to resume flights before the Fall.

"We became a little complacent over seven years," Musk said. "But we learned a really important lesson."

SpaceX had a perfect record of 18 successful trips to resupply the ISS over the past four years under a $1.6 billion contract with NASA. Musk's spaceship was the first commercial vehicle to ever travel to the space station.

The Tesla CEO, who started SpaceX in 2002, also said that last month's mishap will not keep SpaceX from pursuing a renewed contract with NASA, which has invested more than $80 billion in SpaceX.

Just last September, NASA gave the company $2.6 billion to prep Dragon for a mission manned by NASA astronauts. According to Musk, the newest version of Dragon, "Dragon 2," would have survived the malfunction last month.

SpaceX has created emergency evacuation measures for when Dragon carries passengers that allow the rocket to safely evacuate in the event of a malfunction.

But the version of Dragon launched in June wasn't outfitted with those safety features. Musk said all SpaceX flights going forward will be.