What happened
On 26 October 2000, a Beech E90, operated by Rossair Executive Charter (Pty) Ltd, was performing a domestic charter flight from Lanseria to Sishen. While cruising at 20,000 feet, the pilot noticed the cabin door light illuminate, signaling that the door was not properly closed. To manage the pressure differential, the pilot reduced the cabin pressure altitude to 10,000 feet.
As the aircraft descended through 15,000 feet, a loud bang occurred, and the cabin door blew open and became detached from the airframe. Despite this significant event, the pilot managed to continue the approach and completed an uneventful landing at Sishen. There were no injuries among the seven people on board.
The investigation
Investigators examined the aircraft following the incident to determine why the door failed. A physical inspection of the aircraft revealed that the locking mechanism on the aircraft side had not suffered a mechanical failure, as all six latches remained in their correct positions.
Because the door's latches are all connected to a single handle, the investigation focused on the handle's stability. The door itself was not recovered from the accident site, which prevented a full assessment of the door-side hardware.
Findings
- The investigation established that the handle was not secure, leading to the assumption that it moved into the open position during flight.
- The movement of the handle caused all interconnected latches to release simultaneously.
- The loss of the door was the primary factor in the cabin depressurization event.