What happened
On 26 July 2023, a Eurofox 912(S), registration G-CIEF, was performing an aerotow operation at Darlton Airfield in Nottinghamshire. After successfully releasing a glider at approximately 3,000 ft, the pilot began a descending right turn, a procedure consistent with previous flights and standard club practice. The aircraft's descent rate initially reached 3,000 ft/min.
As the aircraft descended, it crossed the runway extended centerline at an altitude of approximately 655 ft. At roughly 1,000 ft, the aircraft transitioned into a descending left turn. During this phase, the bank angle increased progressively, reaching approximately 55 degrees, while the descent rate and airspeed also climbed. The aircraft struck a crop field about one nautical mile from the airfield, resulting in the destruction of the aircraft and the fatal injury of the pilot.
The investigation
The AAIB examined the wreckage, the engine, and various data sources, including FLARM electronic conspicuity data, a tablet-based navigation application, and dashcam footage from a passing vehicle. The investigation found no evidence of mechanical failure or structural fatigue. The engine was inspected at a specialist facility, and no electrical or mechanical issues were identified; the propeller damage suggested the engine was still running at the moment of impact.
Investigators also reviewed the pilot's medical history and the aircraft's maintenance records. The aircraft had been maintained according to the required schedule, with the most recent 50-hour check completed two weeks prior to the accident. The pilot's medical declaration was valid at the time of the flight.
Findings
- The aircraft's flight path transitioned from a normal right turn into an uncontrolled descending left turn.
- There was no evidence of any technical malfunction or structural failure in the aircraft or its engine.
- The pilot may have experienced a partial or full medical incapacitation, which prevented him from maintaining control of the aircraft.
- While a post-mortem examination did not conclusively identify a specific medical event, it could not rule out a stroke or cardiac event, particularly given the pilot's previous medical history involving a stroke in early 2022.