Accident Board Findings

The French Secretariat of State for Transport, Commission of Inquire findings were:

1. Regarding the aft cargo door on the left hand side:

• Service Bulletin 52-37, specifying the installation of a support plate designed to prevent forced closing of the locking handle and the vent door in the case of incomplete engagement of the latching system, had not been applied to the aircraft before delivery and this oversight had not been detected at the time of delivery. It was found, however, that work on the application of this modification had begun on the lock tube where chamfering had been roughly carried out.
• While the aircraft was in service, a modification (direct access to the drive mechanism) had been carried out in a way which did not comply with Service Bulletin 52-38.
• The adjustments of the lock pins and the lock limit warning switch were incorrect.
• The striker of the unlock limit switch had two shims of Douglas origin, surmounted by a shim with no reference and of a quality not to aeronautical standards.

2. During the aircraft's stop at Orly, the aft cargo door on the left-hand side had been closed without any apparent abnormality, the locking handle had been pulled down and the vent door closed, although the lock pins were not engaged and no visual inspection had been made through the view port provided for the purpose of verifying that the lock pins were in place.
3. The takeoff and climb progressed without incident until the aircraft reached approximately 12,000 feet at about 1140 hrs. At that time, the aft cargo door on the left-hand side opened in flight and became detached from the aircraft structure.

Select Next to continue.