What happened
On 25 May 2006, a Cessna 150L, registration G-AZXC, departed from Netherthorpe Airfield for a private flight to Sherburn-in-Elmet. The flight was accompanied by one passenger. During the takeoff roll on the grass runway, the aircraft reached 40 KIAS and rotated at 50 KIAS. After lifting off, the pilot maintained ground effect until reaching 60 KIAS before initiating a climb.
Shortly after the climb began, the engine lost power abruptly. The pilot attempted to restart the engine by pumping the throttle, but the engine remained non-functional. To maintain airspeed, the pilot lowered the nose and targeted a field ahead. While attempting to clear a hedge-lined road, the aircraft struck the ground heavily. The impact caused the nose gear to collapse, and the aircraft subsequently overturned. Both the pilot and the passenger sustained minor injuries and were able to exit the aircraft through the right door without assistance.
The investigation
Investigators examined the fuel system and the aircraft's recent history. During pre-flight checks, the pilot had drained samples from the wing tanks and the gascolator, finding no evidence of water. However, subsequent analysis of the fuel gascolator bowl revealed that approximately two-thirds of the contents were water.
Further inspection by a maintenance engineer revealed that a small amount of a water-fuel mixture drained from the right wing tank's fuel line when the wing was removed. No such liquid was found in the left tank. It was noted that the aircraft had been parked outside during a period of heavy rainfall, with local weather stations reporting significant precipitation in the week preceding the accident. The aircraft had been parked with the right wing low, which may have prevented the pilot from detecting water during the initial sampling process.
Findings
- The sudden engine failure was likely caused by excessive water in the fuel.
- Heavy rainfall during the week prior to the flight, while the aircraft was parked outdoors, was a probable contributory factor in the introduction of water into the fuel system.
- The aircraft's position, parked with the right wing low, likely prevented the pilot from detecting the water during pre-flight draining procedures.