BOAC Flight 712 - Investigation

Investigation

In the subsequent investigation, metal fatigue was ultimately blamed for the failure of the number five compressor wheel in the number two Rolls Royce 508 Conway turbofan engine, starting the rapid chain of failures. The crew's omitting to shut off the fuel to the engine was blamed for the rapid growth of the fire and the loss of the aircraft. Check Captain Moss had accidentally cancelled the fire warning bell instead of the undercarriage warning bell. Moss had also issued orders to Captain Taylor, in breach of the normal protocol for his duties. However, the report on the accident also stated that Captain Taylor had briefed Moss to act as an extra set of eyes and ears inside and outside the cockpit. Moss's actions therefore could be seen as acting within that remit.

As a result of the investigation, and lessons learned from the chain of events, BOAC combined the "Engine Fire Drill" and "Engine Severe Failure Drill" checklists into one list, called the "Engine Fire or Severe Failure Drill". Modifications were also made to the checklist, including adding confirmation that the fire handles had been pulled to the checklist.