What happened
Upon completion of a flight, the aircraft taxied to the arrival gate. During the arrival process, a flight attendant attempted to open the main passenger cabin door to allow passengers to disembark. After finding the door could not be opened, the flight attendant requested assistance from the first officer. The first officer was also unable to open the door, as it remained jammed in the closed position.
A mechanic was summoned to address the issue and gained entry to the aircraft via the galley service door. From inside the passenger cabin, the mechanic manipulated the cabin door opening lever, which successfully opened the door.
The investigation
Maintenance personnel performed an examination of the door following the incident. The inspection revealed that the door was out of adjustment and that certain internal components were inoperative. These specific mechanical anomalies rendered the door dysfunctional under certain operating conditions.
Findings
- The door mechanism was improperly rigged.
- Internal door components were not functioning correctly.
- Neither the operator's maintenance program nor the manufacturer's response to previous reports of recurring jamming events had successfully resolved the recurring discrepancy.