History of the Flight
The helicopter, a Guimbal Cabri G2 registration G-CJEK, departed a private site at approximately 0930 UTC on 20 June 2022 with a pilot and one passenger. The purpose of the flight was for the passenger to experience his first helicopter flight. The aircraft initially flew west, then routed around the Lake District, returning to the landing site about 1 hour and 20 minutes later. The pilot did not report any problems during routine interactions with air traffic control.
Witnesses observed the helicopter approaching the landing site along the River Greta in a westerly direction. Some described the initial approach as normal. Closed-circuit television (CCTV) from a nearby farmhouse captured the helicopter flying west, then making a controlled left turn, heading south with decreasing groundspeed while climbing from approximately 70 ft to 130 ft above ground level. After leaving the camera's view, the helicopter entered an uncontrolled left yaw, initially maintaining altitude before the nose dropped. A witness reported hearing a bang or pop and saw the helicopter in a nose-down attitude descending. The CCTV momentarily captured the helicopter descending nose-down while rotating left before it struck trees. After impact, witnesses heard the engine continue running for about 5 minutes, then a fire broke out. The fire service arrived 39 minutes after the emergency call.
Accident Site
The accident site was in a tree-lined gully within a livestock field, about 100 m south of the River Greta and 250 m west of Bentham Road, near Ingleton, North Yorkshire. Witnesses initially saw the helicopter suspended in a hawthorn tree with the engine running; shortly after, a fire broke out, and the helicopter fell to the ground. The fuselage was destroyed by fire, coming to rest nose vertically downwards, with the main rotor gearbox on top of the gully and landing gear at the bottom. The occupants' bodies were within the wreckage under the engine, and their harness buckles were correctly fastened.
Main rotor blades showed evidence of striking trees with energy, with fragments up to 50 m from the wreckage. Two blades and part of a third were consumed by fire; the remaining blade was misshapen with tree entanglement. The main rotor gearbox casing had partially melted, exposing intact internal gears with no evidence of distress. Blade pitch control links were destroyed by fire. The engine was above the wreckage, front vertically downward, in its support frame. The engine output pulley, rotor input drive pulley, tensioning system, and drive belt were destroyed. The tail rotor came to rest at the bottom of the gully, with about 180° of its structure fire-damaged; all tail rotor blades were present with no leading edge damage. Drive from the tail rotor shaft to the gearbox was confirmed. The tail rotor drive shaft had fractured adjacent to the rear firewall bearing. Continuity of tail rotor pitch control was confirmed from the forward end of the yaw control cable to the blades, but fire damage prevented confirmation of attachment to the pedals. Dual cockpit controls were fitted; cyclic and collective levers were found, but fire melted control rods and mixer unit, preventing confirmation of control continuity.
Recorded Information
CCTV from three cameras at a nearby farmhouse provided about 12 seconds of footage before the helicopter left view, then briefly reappeared. Photogrammetry analysis established the helicopter climbed from about 70 ft to 130 ft agl during a left turn. Groundspeed could not be reliably quantified due to video compression artefacts. The helicopter was not fitted with a crash-protected flight recorder; later Cabri G2 models have a data logger, but G-CJEK, serial number 1151, was not equipped. Radar coverage was lost nine miles northeast of the site due to terrain masking but confirmed flight duration. Radio communications were routine.
Aircraft Information
The Guimbal Cabri G2 is a light two-seat helicopter powered by a Lycoming O-360-J2A piston engine. Drive is transmitted to the three-bladed main rotor via a belt and pulley on the main gearbox input shaft, which also drives the tail rotor shaft and shrouded seven-blade Fenestron tail rotor. The airframe comprises a carbon-fibre main fuselage, engine section, and composite tail boom. The engine is mounted rear of the passenger compartment and drives a pulley; a belt transmits drive to the rotor system via a freewheel coupling and a clutch mechanism that tensions the belt. The main rotor rotates clockwise when viewed from above. In engine failure, the helicopter would yaw right; loss of tail rotor drive would cause left yaw. G-CJEK was built in 2016 and owned by the pilot from new, maintained per the rotorcraft maintenance manual. The last recorded maintenance was a 15-hour airframe and 50-hour/4-month engine inspection in April 2022, at which time the helicopter and engine had 222.8 hours. The technical logs for flights since that maintenance were carried in the helicopter at the time of the accident.
Investigation
The investigation, hindered by fire damage and lack of available evidence, could not reach a definitive conclusion. A number of possible causes were identified but not elaborated.