What happened
On the night of 19 December 2007, a Piper PA-34-220T Seneca III, registration G-LENY, was conducting a commercial charter flight from Oxford to Denham, with a subsequent leg to Plymouth. The aircraft was operated by a single pilot who had been on standby duty earlier that day. During the return leg to Oxford, the flight encountered deteriorating weather conditions, including thick fog and low cloud.
While performing a non-precsion approach to Runway 01 at Oxford (Kidlington) Airport, the aircraft began its descent approximately 2.3 nm earlier than the correct descent point. The aircraft subsequently struck the tops of 60-foot trees near the summit of Wytham Hill, roughly 3.6 nm from the runway threshold. The impact caused the aircraft to break up; a fuel tank exploded, and a post-crash fire ensued. The pilot was located near the burning wreckage with serious injuries, including burns and hypothermia, but survived.
The investigation
The AAIB investigation examined the wreckage, radar data from the Clee Hill area, and the pilot's flight history. Investigators analyzed the aircraft's flight profile, noting that the aircraft was in controlled flight and properly configured for approach, with landing gear extended and flaps set to the first position. Radar data confirmed the aircraft was maintaining the correct altitude until the final stages of the approach, where a slight increase in the rate of descent was observed.
Engine analysis, specifically the damage to the propeller blades, indicated that both engines were producing power at the time of impact. The investigation also reviewed the approach charts and the pilot's reliance on memory rather than active chart reference. The pilot had previously flown the approach and believed the Final Approach Fix (FAF) was at 7 or 8 DME, whereas the actual fix was at 5 DME.
Findings
- The aircraft descended below the required Minimum Descent Altitude (MDA) of 870 ft applicable to the initial part of the approach.
- The pilot was flying the approach from memory and was unaware that the procedure contained a step-down fix.
- The pilot's descent began too early, placing the aircraft on a path that led directly into the terrain.
- Poor weather conditions, specifically the late penetration of low cloud, likely increased the pilot's workload and stress.
- There was no evidence of technical failure or engine malfunction contributing to the accident.