What happened
On 26 February 2009, a Beagle B121 Series 1 Pup, registration G-AXDW, was performing a private flight from Cranfield Airfield toward Sibson Airfield. Upon encountering unfavorable weather conditions near the destination, the pilot decided to return to Cranfield. During this return leg, the aircraft suffered a loss of engine power.
While circling at approximately 1,000 ft to identify a landing site, the pilot attempted to use the carburetor heat and electric fuel pump to restore power. Although the engine briefly regained function, it subsequently faltered and ceased producing useful power. The pilot issued a MAYDAY call to Air Traffic Control and sought a field upwind of the airfield. Due to the presence of electricity pylons, an immediate landing was not possible.
As the aircraft descended through 200 ft, it experienced a significant sink rate, which the pilot attributed to local wind effects. In an attempt to clear a boundary hedge, the pilot pitched up, but the aircraft failed to climb. The aircraft struck a hedge, crossed a road, and passed through a second hedge before coming to rest in a ditch. The pilot escaped without injury, while the passenger sustained minor injuries. The aircraft sustained substantial damage.
The investigation
The investigation focused on the sequence of engine power fluctuations and the environmental conditions at the time of the accident. Investigators examined the pilot's actions regarding the use of carburetor heat and the electric fuel pump. The investigation also noted that the passenger door had jammed during the impact, requiring the occupants to exit through the pilot's door.
Findings
- The loss of engine power was most likely caused by carburettor icing.
- Atmospheric conditions, with a temperature of 9°C and a dew point of 5°C, were conducive to icing.
- A technical engine failure could not be entirely excluded as the engine was not subject to a formal inspection.
- The aircraft's inability to clear the boundary hedge was exacerbated by a loss of altitude during the final approach to the field.