With 4 crew and 21 passengers Fokker F27-200, G-BHMX, was en route from Schiphol Amsterdam Airport to Leeds Airport on a scheduled passenger flight after taking off at 16.20. The flight was cleared directly to FL 140 on route to their destination. Due to the weather, the flight flew in and out of clouds with and an Outside Air Temperature of -20º during the cruise phase flight.
G-BHMX Fokker F27-200 (© cv880m)
During the cruise phase of the flight, the co-pilot (Pilot Flying) noticed a light yaw while at the same time the fire warning light and the feathering pump light came on for the right-hand engine. The commander (who only saw the fire warning light) confirmed that the right-hand engine was the affected engine and completed the fire drill. At the same time, the co-pilot reduced the aircraft speed to the single-engine speed, 140 knots. The fire warning light was extinguished after the first fire extinguisher bottle was fired.
Fokker F27 Cockpit for reference, not from incident aircraft (Source Fokkerairliners) As other aircraft were in a holding due to the weather at Leeds, in accordance with the airlines' procedures, the crew informed ATC of their intention to divert to Humberside. During the descent towards Humberside, 5 minutes after the fire in the right-hand engine the left-hand engine started to run down, with the engine torque and temperature decreasing with the reducing engine speed. The Captain informed ATC of the dual engine failure and that they would make a gliding approach. While gliding down towards Humberside the crew frantically attempted to restart the left-hand engine, at which they succeeded on the second attempt! With one engine running again the approach was continued to Humberside for an ILS aided visual approach to Runway 21, while flying in and out of clouds. As they were flying single-engine the right-hand windshield would not be heated because of load shedding of the electrical system and transferred control to the captain who made a safe landing, stopped the aircraft on the runway and shut the left engine down.
After the landing, the Airport Duty Manager and the Fire Officer inspected the right-hand engine externally and didn't see any sign of fire however noticed that the wing and tail leading edges were covered in a 1.5" to 2" (38-51 mm) thick layer of ice.
The FDR readout from the incident flight (source aaib.gov.uk)
The airlines engineering department investigated the engine fire and failure. Also, the fuel was tested, first for water and later if it was confirmed to the specifications. All without any findings. Subsequent engine runs and a test flight did not reveal any faults, and the aircraft was returned to service.
No conclusive evidence was found, but it was suspected that;
The left-hand engine failed due to icing
The right-hand engine fire alarm was a false warning
The full investigations report can be read by clicking here.