History of the Flight
The pilot, a commercial licence holder with 903 hours total flying experience (1 hour on type), was tasked with collecting the aircraft from Tilstock Airfield in Shropshire and returning it to its home base at Headcorn (Lashenden) in Kent. He travelled by train to Shropshire, arriving around 1320 hrs, and encountered delays due to incomplete aircraft documentation. The aircraft, a Cessna T206H Turbo Stationair (registration G-KIKX, serial number T20608267, manufactured 2001), had a single Lycoming TIO-540-AJ1A piston engine.
After resolving the documentation issue, the pilot noted the fuel load of approximately 30 US gallons was insufficient. He was advised that fuel was unavailable at Tilstock but could be obtained at Sleap Airfield, about 7.5 nm away. The aircraft's GPS navigation unit had a defective screen obscuring the first character of waypoint entries, a defect noted during earlier training. The pilot departed Tilstock shortly before 1700 hrs and arrived at Sleap, where the aircraft was refuelled to full. He contacted his manager at Headcorn for a weather briefing and was told conditions were workable but with a cloud bank to the east; he was advised to call the control tower but did not do so.
The pilot departed Sleap for Headcorn at approximately 1710 hrs (reports from Sleap indicated 1720 hrs) on a VFR flight of at least 172 nm. Sunset was at 1757 hrs, so the landing was expected in twilight or darkness; the runway at Headcorn was unlit.
The Accident
The flight was uneventful until reaching North Kent as daylight faded. The pilot confirmed his position over the Lambourne VOR/DME using GPS and VOR equipment, then set the GPS to navigate directly to Headcorn (entering the ICAO code EGKH, he thought). The resulting track and distance appeared correct. The aircraft encountered increasing cloud and flew above an overcast layer. With approximately 7 nm to run to the GPS destination, the pilot commenced a descent through cloud, aiming to remain at or above 600 ft (Headcorn airfield elevation is 72 ft). The aircraft descended below 600 ft; as the pilot applied power, the aircraft struck terrain at an elevation of about 580 ft amsl. The engine stopped abruptly, the aircraft pitched nose-down and slid on its main wheels and forward fuselage before coming to rest.
The pilot, who sustained minor injuries, vacated the aircraft and telephoned the police, reporting his position as north-west of Headcorn. He then returned to the aircraft to make it safe. After about an hour with no help arriving, he re-powered the GPS and entered EGKH as the destination, which indicated his position as approximately 8 nm north-east of Headcorn, not north-west. The aircraft had crashed near Challock gliding site (ICAO: EGKE), elevation 600 ft amsl, on relatively flat terrain. The safety altitude for the area was 2,400 ft based on a mast 16.5 nm north-west of Headcorn.
Further Investigations
Further enquiries revealed that during a demonstration flight and differences training prior to the ferry flight, it had been made clear that the aircraft's GPS navigation database had expired and was not usable; pilots were advised to use a portable GPS unit.
Pilot's Assessment and AAIB Comment
In his report, the pilot identified fatigue, time pressure, and poor decision-making as contributing factors. He believed he had made a GPS input error, likely selecting Challock (EGKE) instead of Headcorn (EGKH) due to the defective screen, fatigue, and time pressure. The AAIB commented that the pilot could have delayed the flight but instead proceeded in an unfamiliar aircraft, in less-than-ideal weather, with an estimated time of arrival after dark at an unlit airfield, without a planned alternate, and in a fatigued state. The AAIB noted that the decision to descend below the safety altitude without visual references, using the GPS as primary navigation, was the primary cause of the accident. The proximity of the two airfields (Challock and Headcorn) meant that the GPS track and distance were not grossly in error, reducing the likelihood of detection without thorough pre-flight preparation and positional awareness.