What happened
On 2 October 2019, a student pilot was conducting a solo circuit flight for training purposes in a Robinson R44 II, registration G-LLIZ, at Sherburn-in-Elmet Airfield in Yorkshire. Following the completion of the third circuit, the pilot noticed that a jacket, which had been placed on the left seat and secured with a seat belt, had shifted position near an open vent.
Before commencing the fourth circuit, the pilot reached toward the left side of the cockpit to retrieve the item. During this movement, the jacket became entangled with the left collective lever. As the pilot pulled the jacket, the lever was inadvertently raised, increasing the pitch of the rotor blades. This caused the aircraft to pitch nose up, resulting in the tail stinger striking the ground. The aircraft then yawed to the left and rolled onto its right side. The pilot sustained one injury (a head injury) but was able to exit the aircraft. The helicopter sustained damage beyond economic repair.
The investigation
The investigation examined the sequence of events using airfield CCTV, which showed the entire accident sequence lasting approximately four seconds. Investigators looked into the configuration of the cockpit, noting that while the pilot was flying solo, the dual controls remained installed. The investigation also reviewed the pilot's pre-flight actions, specifically the decision to open vents to clear a carbon monoxide light and the subsequent placement of the jacket on the unoccupied seat.
Findings
- The pilot reached for the jacket after completing the pre-flight checklist, leaving the item unsecured.
- The jacket became caught around the left collective lever, causing an unintended increase in blade pitch.
- The sudden pitch up caused the tail stinger to contact the ground, initiating a roll.
- The pilot's physical movement while reaching across the cockpit may have also caused an unintentional application of the left pedal, contributing to the yaw.
- The use of friction devices on the controls was not employed because the pilot intended to take off shortly after the retrieval.