PORTLAND, Ore. ( KOIN ) — The four bolts missing from the door plug that ejected from Alaska Airlines Flight 1282 shortly after takeoff on Jan. 5 were removed during repairs to the plane’s frame during the manufacturing process, a preliminary report published by the National Transportation Safety Board states. Evidence suggests the bolts were never replaced before the plane was put into service.
The bolts were initially removed to make repairs to five damaged rivets on the Boeing 737 MAX 9’s edge frame, which were discovered near the door plug on Sept. 1. However, a photo taken by a Boeing employee on Sept. 19 shows that the two “vertical movement arrestor” bolts and two “upper guide track” bolts, which prevent the door plug from moving upward, were not replaced following the repairs made by Spirit AeroSystems, the report states.
“Overall, the observed damage patterns and absence of contact damage or deformation around holes associated with the vertical movement arrestor bolts and upper guide track bolts in the upper guide fittings, hinge fittings, and recovered aft lower hinge guide fitting indicate that the four bolts that prevent upward movement of the MED plug were missing before the MED plug moved upward off the stop pads,” the report states.