SpaceX CRS-7 launch and landing attemptJuly 20, 2015 Update: CRS-7 Investigation UpdateMore Like This
Summary: Preliminary analysis suggests the overpressure event in the upper stage liquid oxygen tank was initiated by a flawed piece of support hardware (a “strut”) inside the second stage which failed approximately 138 seconds into flight. The pressurization system itself was performing nominally, but with the failure of this strut, the helium system integrity was breached. This caused a high pressure event inside the second stage within less than one second and the stage was no longer able to maintain its structural integrity. The strut (supplied by an outside contractor) was designed and material certified to handle 10,000 lbs of force, but failed at 2,000 lbs, a five-fold difference.
Despite the fact that these struts have been us