January 3, 2017
SpaceX completes explosion analysis, on track for Jan. 8th return to flight
SpaceX is now aiming at Jan. 8 for its return to spaceflight after finishing its analysis of a launch pad explosion in September that ripped apart a Falcon 9 rocket and a commercial communications satellite from Facebook.
Once approval has been granted by the Federal Aviation Administration, SpaceX is slated to launch ten satellites from a Falcon 9 rocket for Iridium Communications Inc. from Vandenberg Air Force Base. The satellites will be components of Iridium’s new satellite constellation to supply mobile communications functions on land and on ships and airplanes.On Monday, the communications company tweeted that it was “pleased with SpaceX’s announcement and targeted launch date.”
In the weeks following the explosion, SpaceX said it projected to come back to flight once in November. However, as the investigation prolonged, that predicted launch date was pushed back to December, and then January.
At one point, SpaceX founder and tech mogul Elon Musk called the investigation as “the toughest puzzle to solve that we’ve ever had to solve.”
The September explosion ruined a satellite that was to be maintained by Israeli satellite operator Spacecom and was also to assist Facebook Chief Executive Mark Zuckerberg achieve his stated goal of providing high-speed Internet access to out of the way parts of Africa.
Difficult to Pin Down Cause of Explosion
In its most recent update, SpaceX said it combed through 3,000 channels of video and telemetry information that lasted just 93 milliseconds from the first hint of problems to the explosion.
The company said one of three composite overwrapped pressure tanks, inside the rocket’s bigger, second-stage liquid oxygen tank broke down, most likely after a buildup of liquid oxygen between the vessel’s inner liner and its overwrap ignited.
The tanks are used to keep cold helium that sustains pressure in the liquid oxygen tank. As the liquid oxygen is used up, the helium rushes in to fill the void.
SpaceX said its investigation team discovered “buckles,” in the tanks' liners. Liquid oxygen is capable of gathering and getting trapped in these valleys, and “breaking fibers or friction can ignite the oxygen in the overwrap,” causing failure, SpaceX said.
The company also reported that the oxygen fuel may have been to cold, to the point that solid oxygen may have formed, which would have made the issue of trapped oxygen even worse.
SpaceX has announced several short term fixes, but said it plans to completely redesign the problematic vessels.
If the FAA does give its approval, the next few launches will be crucial for the space exploration company.
Image credit: SpaceX