Despite extensive air and sea searches, no remains of the nine victims lost in flight were found at sea. Multiple small body fragments and pieces of clothing were found in the Number 3 engine, indicating that at least one victim ejected from the fuselage was ingested by the engine, but whether the fragments were from one or more victims was not known.
Based on developments after it issued its original report in April 1990, the NTSB issued a superseding accident report on March 18, 1992. In this report, the NTSB determined that the probable cause of the accident was the sudden opening of the cargo door, which was attributed to improper wiring and deficiencies in the door's design. It appeared in this case that a short circuit caused an unordered rotation of the latch cams, which forced the weak locking sectors to distort and allow the rotation, thus enabling the pressure differential and aerodynamic forces to blow the door off the fuselage; ripping away the hinge fixing structure, the cabin floor, and the side fuselage skin; and causing the explosive decompression.