What happened
On 4 November 2021, a pilot operating a Chayair Sycamore Mk.1 gyrocopter, registration ZU-BZE, was preparing for flight operations at Farm Klipdrift in the Free State. The flight was intended to be a private operation consisting of circuits around the farm under visual meteorological conditions.
After completing standard pre-takeoff checks and the pre-rotation sequence, the pilot released the brakes to begin the takeoff roll on the grass runway. During this acceleration, the nose gear encountered a bump in the terrain. This impact caused the aircraft to bounce, leading to a sudden upward movement of the main rotor. The resulting rotor flap caused the blades to strike the vertical fin and tail assembly. The pilot immediately aborted the takeoff and returned the aircraft to the hangar.
The investigation
The investigation examined the aircraft's maintenance history and the condition of the takeoff area. Records indicated that the aircraft had undergone its last annual inspection on 8 March 2021, with only 22.2 airframe hours accumulated since that service. No mechanical defects were reported or identified prior to the event, as all structural damage was directly attributed to the impact of the rotor blades against the tail components. Following the incident, the runway surface was scraped to remove the bumps that caused the disturbance.
Findings
- The primary cause of the accident was the nose gear striking a bump on the grass runway.
- The impact caused the aircraft to bounce, triggering the main rotor to flap into the vertical fin and tail.
- The aircraft sustained substantial damage to the main rotor blades, the vertical fin, and the tail section.
- The pilot was not injured during the occurrence.
Safety action
As a safety message, it is advised that gyrocopter pilots perform thorough runway inspections prior to takeoff to identify potential surface hazards. Additionally, a recommendation has been made for the Director of Civil Aviation to consider implementing specific runway safety requirements for gyrocopter operations under Part 94 of the Civil Aviation Regulations.