Aircraft and Flight Details
The aircraft, a Reims Cessna F406 Caravan II with registration G-TWIG, was built in 1987 and powered by two Pratt & Whitney Canada PT6A-112 turboprop engines. On 22 October 2004, it was operating a public transport (non-revenue) freight flight. The commander, aged 35, held an Airline Transport Pilot Licence and had 2,735 total flying hours, including 510 hours on type. The flight was the fifth sector of the day, delivering newspapers and magazines to the Northern and Western Isles, with the final leg from Stornoway to Inverness.
History of the Flight
The aircraft departed Stornoway at 1015 hrs, climbing to Flight Level (FL) 95. At 1029:07 hrs, the pilot contacted Lossiemouth Radar and requested descent. The controller cleared the aircraft to descend to FL75, and the pilot acknowledged in a clear, unhurried voice. This was the last transmission. At 1032:59 hrs, the controller advised the pilot of temporary loss of radar contact and reduced service to a Flight Information Service; no reply was received. Repeated attempts to contact the aircraft failed. At 1036 hrs, Lossiemouth ATC initiated search and rescue actions. The wreckage was discovered the following day at 1330 hrs on Meall Feith na Slataich, a mountain ridge at 2,480 ft elevation, 30 nm north-west of Inverness. The aircraft had struck the ground in a steep left spiral dive, with extreme fragmentation indicating a high impact speed, likely around 350 kt. Witnesses in the area reported hearing a loud bang at about 1030 hrs.
Pilot Information
The pilot began flying training in the USA in 1998 and obtained commercial and instructor qualifications. He returned to the UK and earned a Commercial Pilot Licence in March 2001. He had flown various aircraft including the Dornier 228 and was due to leave his current employer to join a short-haul jet operator. On the day of the accident, he was in a normal, happy mood and had swapped duties to make the Stornoway flight his last in the F406 type before departing.
Investigation Findings
The AAIB investigation discounted major airframe and powerplant failures. The available evidence indicated that the aircraft's descent rate became unsteady and it turned left shortly after initiating descent. The aircraft struck the ground in a steep left spiral dive with no evidence of an attempted recovery. No emergency call was transmitted, and the pilot gave no indication of any problems. The investigation concluded that there was insufficient evidence to draw firm conclusions about the reasons for the sudden deviation from controlled flight. Two safety recommendations regarding flight recorders, previously made to the European Aviation Safety Agency (EASA), were reiterated.