SpaceX Knows What Happened on September 1, But Not Why

SpaceX is still studying 3,000 channels of engineering data to determine the root cause of the September 1 on-pad fire that destroyed a Falcon 9 rocket and the Amos-6 communications satellite. A preliminary review has determined it was a breach of a second stage helium system, but why it happened still is unknown. The company nevertheless said it anticipates returning to flight as early as November.

The “anomaly” took place during a routine pre-launch test two days prior to when the launch was scheduled.

In a statement on its website, the company says a “large breach in the cryogenic helium system of the second stage liquid oxygen tank took place. All plausible causes are being tracked in an extensive fault tree and carefully investigated.”

The only Falcon 9 launch failure to date, on June 28, 2015, was also caused by a problem in the second stage. In that case, SpaceX was launching its seventh Commercial Resupply Services (CRS) mission, CRS-7, for NASA to deliver cargo to the International Space Station (ISS) aboard its Dragon spacecraft. Dragon and the cargo were destroyed.

Although that failure and the September 1 anomaly involved the second stage, SpaceX says that “we have exonerated any connection with last year’s CRS-7 mishap.”

The Amos-6 satellite that was lost is a commercial satellite owned by Israel’s Spacecom, so this was a commercial launch for a commercial customer. The

FAA regulates commercial space launches like this one and under its rules the launch service provider, not the government, is in charge of the investigation. However, the launch service provider, SpaceX in this case, may invite whoever it wants to participate in the investigation.

SpaceX said the Accident Investigation Team includes SpaceX, the FAA, NASA, the U.S. Air Force, and industry experts. NASA and the Air Force are SpaceX customers, and Space X leases launch pads from both agencies.

This anomaly took place at Cape Canaveral Air Force Station’s (CCAFS) Launch Complex 40 (LC-40). SpaceX says that “substantial areas of the pad systems were affected,” but others were not, including the Falcon Support Building and a new liquid oxygen tank farm.

CCAFS is adjacent to NASA’s Kennedy Space Center (KSC) and SpaceX also leases NASA/KSC’s Launch Complex-39A for launches of both Falcon 9 and the larger Falcon Heavy. SpaceX had planned the first test flight of Falcon Heavy from LC-39A this year. The statement did not indicate whether plans to resume flights in November assumed use of LC-40 or LC-39A.

SpaceX also leases an Air Force pad at Vandenberg Air Force Base, CA for launches to polar orbits and is building its own launch site near Brownsville, TX.