What was found
THE MAIN CABIN DOOR PRESSURIZATION LOAD IS CARRIED BY 10 SQUALLS (BOLT STOPS). FOUND THE 1 NUT AND STUD PORTION MISSING ON POST FLIGHT. THE CONTACT HEAD WAS STILL IN PLACE SO PRESSURIZATION LOAD WAS DISTRIBUTED NORMAL. BOLT WAS REPLACED, WITH FAILED UNIT SENT TO MFG. MFG DETERMINED HYDROGEN EMBRITTLEMENT WAS ROOT CAUSE. AT A LATER DATE FOUND ANOTHER BOLT WITH THE CONTACT SURFACE CRACKED. REMOVED ALL REMAINING BOLTS (9) AND FOUND 6 VISUALLY WERE CRACKED UNDER THE HEAD.