What happened
On 6 June 2006, a Robinson R44 Astro, registration G-RONN, was preparing for a solo cross-country navigation training flight at Netherthorpe Airfield in Nottinghamshire. Prior to departure, the student pilot had placed a map between the seat and the door. As the helicopter lifted off, the map fell into the footwell.
In an attempt to retrieve the map, the pilot leaned forward, which inadvertently moved the flight controls and caused the aircraft to lurch to the right. This movement pushed the map further under the pedals. The pilot reported that the situation caused a sense of panic, leading him to instinctively depress the left yaw pedal, mimicking the action of applying a brake in a car. This input caused the helicopter to rotate rapidly to the left, completing at least one full rotation.
Unable to regain control, the pilot attempted an emergency landing. While the aircraft remained upright, the rear of the right skid struck the ground, causing the airframe to twist. During the incident, the pilot attempted to shut down the engine by cutting the mixture, but the engine and main rotor gearbox oversped before the engine could be stopped. There were no injuries to the pilot.
The investigation
Investigators examined the wreckage and the pilot's account of the flight. The post-accident inspection of the Robinson R44 Astro revealed that the airframe had sustained significant distortion. This structural damage had specifically affected the engine controls, which had prevented the pilot from being able to close the throttle during the emergency.
Findings
- The primary cause of the loss of control was the unintentional control input caused by the pilot's attempt to retrieve a map during the takeoff phase.
- The pilot's instinctive reaction to apply the left pedal as a braking mechanism contributed to the rapid leftward rotation of the aircraft.
- The engine and gearbox oversped because the distorted airframe prevented the immediate closure of the throttle.