Description

On 19 May 2004, a Bombardier DHC8-400 being operated on a scheduled passenger flight from Sandefjord to Bergen by Norwegian airline Wideroe was climbing through 13500 ft approximately 20 nm west north west of Sandefjord in day Visual Meteorological Conditions (VMC) when there was a loud 'bang' from the left engine followed quickly by total power failure and a fire warning for that engine. The crew carried out the Quick Reference Handbook (QRH) drill, declared an emergency and made a return to Sandefjord. Although the left hand engine was shut down and both engine fire bottles had been discharged, the engine warning remained illuminated throughout the remainder of the flight. The aircraft was stopped on the runway after landing and a successful emergency evacuation of all 31 occupants was carried out with no injuries whilst the Airport Fire Service attended to the fire source.

Investigation

An Investigation was carried out by the Accident Investigation Board Norway (AIBN).

It found that the sudden shut down of the left engine was made automatically by the FADEC and was then followed by execution of the prescribed flight crew emergency drill. The shut down was found to have occurred as the result of a fatigue fracture in one of the low pressure compressor first stage rotor blades. Vibration due to this blade fracture led to major internal damage in the engine and caused an oil leak in the fuel heater. This oil flowed backward and was ignited by the hot exhaust gases at the rear of the engine. The fire caused major damage to the engine and caused the fire alarm annunciation to continue after the fire had gone out and the engine had cooled completely.