What happened
On 6 July 2023, a Piper PA-23-250, registration G-BKJW, crashed approximately 1 nautical mile south-west of Bagby Airfield in North Yorkshire. The pilot, the sole occupant of the aircraft, had completed a multi-leg flight involving stops in France and Ireland before returning to the UK.
During the final approach to Bagby, the pilot made a routine radio call reporting his position four miles from the airfield. However, shortly after joining the right base leg for Runway 06, the aircraft entered a steep, wings-level, nose-down descent. CCTV footage and radar data confirmed that the descent angle steepened sharply before the aircraft struck trees and the ground at an angle of approximately 35° to 40° nose-down. The impact triggered a significant post-crash fire, and the pilot sustained fatal injuries.
The investigation
Investigators examined the wreckage and surveillance data to determine the cause of the sudden pitch change. While the post-impact fire destroyed much of the physical evidence, the remaining components showed no mechanical failures in the control cables or the horizontal stabilator.
One significant anomaly was discovered: the pitch trim drum was found positioned nearly at the full nose-down limit. This position was inconsistent with the aircraft's flight configuration at the time of the descent. The investigation also reviewed the aircraft's systems, noting that the autopilot was placarded inoperative but had been used, and that the electric trim circuit breaker was difficult to locate. The investigation also considered whether a sudden flap retraction could have caused the pitch change, but a pitch trim runaway was identified as the most probable cause.
Findings
- The aircraft entered a sudden, steep descent while on the base leg of the landing circuit.
- There was no evidence of a stall, pilot incapacitation, or a failure in the mechanical flight control cables.
- The pitch trim drum was found in a nearly full nose-down position, which was unexpected for the aircraft's speed and configuration.
- A pitch trim runaway was considered the most likely cause, though insufficient evidence could definitively confirm it.
- The pilot had not completed specific differences training for this aircraft type and may not have been aware of the training requirements.
- The electric trim circuit breaker was difficult to identify and reach in an emergency.
Safety action
Following the investigation, the CAA has committed to several safety initiatives, including:
- Developing new educational materials and webinars regarding the management of trim runaways.
- Reviewing guidance for pilots on the use and deactivation of inoperative autopilots.
- Updating training requirements and examiner guidance to include specific references to autopilot and electric trim failures.
- Considering the use of identifiable markers, such as coloured caps, on circuit breakers to assist pilots in rapid identification during emergencies.