What happened
On 16 December 2009, a Bombardier Dash 8 Q400, registration G-JECZ, was conducting a commercial passenger flight when the flight crew noticed an illuminated warning caption in the cockpit indicating that an engine air intake heater adapter had overheated. Simultaneously, an electrical burning smell was detected in the cockpit.
During the descent, the smell intensified and became noticeable within the passenger cabin. The crew initially struggled to communicate due to a disconnected microphone jack, but once communication was restored, the commander decided to divert the aircraft to Manchester Airport. During the final approach, two passengers observed sparks emitting from the rear of the right engine. This prompted the commander to declare a mayday. The aircraft landed safely at Manchester, where the engines were shut down and the 45 passengers and 4 crew members evacuated the aircraft without injury.
The investigation
Following the event, an engineering examination was conducted by the aircraft operator. The inspection revealed that the engine air intake heat adapter on the right engine had experienced a mechanical failure due to overheating. Both the left and right engine intake heat adapters had undergone inspection and testing only three days before the incident. The investigation also noted that the specific unit involved had been in service for over 4,000 cycles.
Findings
- The right engine air intake heat adapter overheated, leading to its mechanical destruction.
- The crew's ability to communicate was briefly hindered by a microphone jack that was not properly seated in its socket.
- There were no injuries to the 45 passengers or 4 crew members during the evacuation.