Piper PA-46-500TP Meridian N961JM Accident at Dunkeswell Aerodrome

Accident Overview and Aircraft Details On 31 December 2002 at 1749 UTC, a Piper PA-46-500TP Meridian, registration N961JM, was damaged beyond economic repair during an approach to Dunkeswell Aerodrome in Devon. The aircraft, manufactured in 2002 and powered by a single Pratt & Whitney PT6A-42A turboprop engine, was operating a private flight with one crew member and one passenger on board. Both occupants sustained no injuries. ## Flight Profile and Pre-Departure Planning The pilot, a 39-year-old Airline Transport Pilot with an instructor rating and 8,899 total hours (2,095 on type), departed Chambery, France, at 1605 UTC for Dunkeswell Aerodrome, with Exeter Airport designated as the diversion. Prior to departure, the pilot reviewed available TAFs and METARs for Exeter and nearby airfields and was satisfied that conditions were suitable. At approximately 1530 UTC, the pilot also contacted a friend, a commercial pilot living near Dunkeswell, who estimated the cloud base to be around 1,500 feet. The flight proceeded uneventfully at FL270, aside from some airframe icing on departure. Approaching the south coast of England, the aircraft descended to FL60 and left controlled airspace at Southampton in good visual meteorological conditions (VMC), with south coast lights clearly visible. At 1720 UTC, Exeter weather reported surface winds of 130°/08 kt (varying 110°–170°), visibility of 6,000 metres, scattered cloud at 500 feet, broken cloud at 1,200 feet, temperature +9°C, dew point +8°C, and QNH 1011 mb. ## Approach and Accident Sequence With approximately 50 miles remaining to Dunkeswell, the pilot attempted to contact Dunkeswell Radio but received no reply, assuming the airfield had closed for the night. The lights of Dunkeswell village and an industrial site at the aerodrome’s north-eastern edge were visible but appeared milky, as if seen through scattered mist pockets. The aircraft descended to 2,600 feet on the Exeter QNH, and the main altimeter was set to the Dunkeswell QFE by subtracting 31 mb from the Exeter QNH to account for the aerodrome’s 850-foot elevation. The pilot used two GPS navigation systems programmed to provide centreline information for Runway 23 on a Course Deviation Indicator (CDI) with a 0.3 nm full-scale deflection. Although Dunkeswell had no runway lighting, the pilot had placed white reflective panels (18 cm by 9.5 cm) on the right edge of Runway 23, mounted vertically on low black plastic supports. These panels were intended to show the right runway edge and touchdown zone when illuminated by the aircraft’s landing light. The Runway 23 threshold was displaced 290 metres from the road along the northern aerodrome boundary, with the first reflector positioned 220 metres beyond the displaced threshold. Reflectors were spaced over 460 metres, with intervals varying between 15 and 49 metres. The white centreline markings would also have been visible in the landing light at low altitude. The end of the 46-metre-wide runway was 280 metres from the last reflector. The pilot had previously conducted numerous night approaches and landings to Runway 23 using similar visual references. The pilot identified the industrial site lights earlier than expected, at six miles, while maintaining 2,600 feet on the Exeter QNH. He then cancelled his radar service from Exeter, which had been providing ranges and bearings from Dunkeswell, and made blind transmissions on the Dunkeswell Radio frequency regarding his position and intentions. During the final approach, the pilot observed scattered cloud near the approach path. At approximately 2.5 nautical miles from the runway threshold and 800 feet above ground level, the pilot noticed a mist pocket ahead and decided to initiate a go-around and divert to Exeter. At that point, the aircraft had the second stage of flap extended, landing gear down, airspeed reducing through 135 kt, and all three landing lights on. The pilot increased power and began a climb but regained visual contact with the runway, prompting him to reduce power and resume the approach. A high rate of descent developed, and the radio altimeter’s automatic 50-foot audio warning sounded. The pilot began to increase engine power but was unable to prevent a severe impact with terrain. The aircraft’s wings were torn off as it passed between two trees, and the fuselage continued across a grass field, remaining upright until it came to a stop. ## Post-Accident Actions and Weather Data The passenger immediately exited the aircraft through the normal passenger cabin exit and returned to assist the pilot. After shutting off the electrical and fuel systems, the pilot also exited through the normal exit. A leak developed from the oxygen system, which had been disrupted in the accident, and the pilot was unable to remove the fire extinguisher from its stowage due to airframe deformation. The pilot contacted Exeter Air Traffic Control (ATC) via mobile telephone to report the accident, and emergency services were dispatched. An automatic meteorological recording station at Dunkeswell, which provides data to the Meteorological Office at Bracknell but is not available to the aerodrome or broadcast to pilots, recorded the 1700 UTC weather as surface wind 140°/11 kt, visibility of 100 metres in fog, and sky obscured. The 1800 UTC report indicated surface wind 150°/10 kt, fog, and sky obscured. ## Investigation Findings The pilot concluded that the fog and scattered mist/cloud may have caused him to misinterpret the distance to the runway, which he had estimated using visual orientation from the industrial site lights, a mast on the aerodrome’s south perimeter, and an aerial beside its north perimeter. The radio altimeter’s selectable audio warning was set at 500 feet, which was the height at which the go-around was initiated; the pilot believed he may have missed the audio warning due to concentration on the approach. A 200-foot-deep, steep-sided valley ran from left to right across the final approach track. As the aircraft crossed the rising ground of the valley side, the height above ground indicated by the radio altimeter decreased rapidly, triggering the 50-foot audio warning. The investigation concluded that the accident occurred due to an attempt to land at night in fog at an airfield with no runway lighting and only limited cultural lighting for visual orientation. These visual references were lost when the aircraft entered the fog. The aircraft impacted the treeline at the top of the valley 1,600 metres short of the displaced threshold and 200 metres to the right of the centreline.