Elon Musk calls SpaceX blast a 'most difficult, complex failure'

SpaceX founder andchief Elon Musk said on Friday he was unsure why one of thecompany's Falcon rockets burst into flames on its Florida launchpad last week, destroying both the rocket and an Israelicommunications satellite it was due to lift into orbit.

"Still working on the Falcon fireball investigation. Turningout to be the most difficult and complex failure we have everhad in 14 years," Musk, the billionaire entrepreneur who is alsothe chief executive of Tesla Motors, wrote on Twitter.

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A SpaceX-led accident investigation is underway, overseen bythe Federal Aviation Administration's Commercial SpaceTransportation office.

A massive fireball enveloped the rocket on Sept. 1 as it wasbeing fuelled for a routine test of its first stage. The rocketwas scheduled to blast off two days later.

The rocket's nine engines had not yet ignited for a testfiring when a fireball engulfed the upper stage. "There was noapparent heat source," Musk said on Friday.

The accident destroyed the $200 million US communicationssatellite owned by Israel-based Space Communication,which was going to be used by Facebook and Eutelsat toexpand internet access in Africa.

Hawthorne, California-based SpaceX has not yet said how muchdamage was done to its launch pad, located at Cape Canaveral AirForce Station.

SpaceX has a backlog of more than 70 launches for commercialand government customers, worth more than $10 billion.

The rocket that was destroyed was the second of 29 Falcon 9rockets to fail. It took SpaceX about three weeks to identifythe likely cause of its previous accident, which occurred onJune 28, 2015.

The problem was traced to a faulty bracket, which washolding a bottle of helium inside the rocket's upper stage. Whenthe strut broke about two minutes after liftoff, the upper-stageliquid oxygen tank over-pressurized and ruptured, triggering anexplosion.

SpaceX rocket explodes on the pad

8 years ago

Duration 2:10

A rocket belonging to private company SpaceX exploded in Cape Canaveral, Fla. today, destroying the satellite inside.

SpaceX replaced thousands of struts throughout its fleet andhad successfully flown nine times before last week's failure.

"We remain fully confident in the results of (that)investigation ... The current investigation has no bearing onthis," SpaceX spokesman Dex Torricke-Barton wrote in an email toReuters.

SpaceX's next flight had been slated for later this monthfrom a second launch pad at Vandenberg Air Force Base inCalifornia.

"We have confidence that SpaceX will resolve the matter andwhen they do we will be ready to launch," SpaceX's customer,Iridium Communications Inc, told Reuters on Friday.

SpaceX said last week it was looking to shift its Floridalaunches to a nearly completed pad at NASA's Kennedy SpaceCenter, adjacent to its Cape Canaveral site.