What happened
On 22 June 2014, a Mainair Rapier, registration G-MZNU, was conducting a private flight at an altitude of approximately 2,000 ft when the engine began to run roughly before failing completely. In response to the loss of power, the pilot performed a forced landing into a wheat field located at the Lansil Golf Course in Lancaster, Lancashire.
During the landing sequence, the aircraft experienced rapid deceleration and rolled onto its side. Both the pilot and the single passenger sustained minor injuries, and both individuals were able to exit the wreckage without assistance. The aircraft sustained damage to its wing keel and pod.
The investigation
Investigators examined the aircraft's fuel system following the engine failure. The inspection revealed that the fuel filter was obstructed by very fine silt. This silt was also present at the bottom of the metal fuel container used during the most recent refueling operation.
Further examination of the metal container indicated that internal corrosion had begun to occur, which likely contributed to the contamination of the fuel supply. While the pilot typically used a strainer during the refueling process, it was determined that the mesh size of the strainer was inadequate to prevent the fine debris and silt from entering the aircraft's fuel system.