Accident Overview
On 27 September 2024 at 1559 UTC, a Guimbal Cabri G2 helicopter, registration G-FICH, was involved in an accident at Leicester Airport during a training flight. The helicopter was manufactured in 2015 (serial number 1131) and powered by one Lycoming O-360-J2A piston engine. The flight was an instructional sortie with a commander (aged 40, holding a Commercial Pilot’s Licence with 314 total hours, 212 on type) and a student on board. No passengers were carried.
History of the Flight
The flight departed Leicester Airport for revision exercises at altitude before returning for hovering practice. While moving forward very slowly in a hover, the helicopter began to yaw to the left. The yaw rapidly accelerated, and G-FICH completed four rotations before striking the ground. The helicopter came to rest on its left side. Both pilots egressed; the student sustained minor injuries, and the commander reported no injuries. Four days after the accident, the commander was found unresponsive at home due to a basilar artery thrombosis and died three days later. Medical expertise concluded the thrombosis was unrelated to the accident.
Accident Site and Damage
The helicopter came to rest on its left side near the hover location. The cabin and cockpit had minor damage. The main rotor blades were severely damaged, the tail boom separated, the right door detached, and the skids slid sideways. The maintenance organisation disconnected the tail rotor control rod to facilitate transport.
Recorded Information
The helicopter was equipped with a GoPro camera in the overhead panel, but the flight was not recorded. CCTV footage from the airport captured the accident sequence. The wind was steady from the northwest at 16 to 24 kt, with good visibility and no cloud below 3,400 ft.
The CCTV showed G-FICH moving slowly forward into wind before yawing rapidly left. The first rotation was roughly level; during the second rotation the helicopter descended, then climbed vertically during the third rotation (likely from collective increase), and descended again during the fourth rotation before ground contact with the rear skids and tail.
Aircraft Information
The Guimbal Cabri G2 is a two-seat light helicopter used primarily for training. G-FICH had dual controls with yaw pedals on both sides. The right-side pedals were adjustable (two positions), while the left-side pedals were fixed and non-adjustable. The manufacturer initially fitted non-adjustable pedals on both sides but switched to adjustable right-side pedals from 2011 onward. Adjustable left-side pedals were available as a factory option or retrofit. Following this investigation, the manufacturer plans to install adjustable left-side pedals as standard on new models. No guidance on pilot height or leg length for pedal adjustment was published.
Yaw Control and Training
The Cabri G2 uses a fenestron instead of a conventional tail rotor. The yaw control is immune from stall or vortex ring states but requires greater pedal input during approach to the hover due to the large vertical fin. Wind from the right can decrease fenestron effectiveness. The manufacturer's Service Letter 12-001 A identifies factors that exacerbate left yaw: instinctive collective raising, wind from the right with slow pilot reaction, and high altitude conditions. For G-FICH, the first two factors applied. The manufacturer demonstrated that applying and maintaining full opposite pedal will stop rotation. It is likely that full pedal was not applied or held long enough.
Examination and Safety Action
Examination of the helicopter revealed no technical faults. The manufacturer has taken safety action to install adjustable pedals in the left seat of all new Cabri G2 models and to add a pre-flight check of fenestron travel.