What happened
On 27 June 2011, a Robinson R22 Beta II, registration EI-EAS, was involved in an accident in Hazelwood, Co. Sligo, while performing a private flight. After landing in a large grassland field earlier that afternoon, the pilot intended to take a passenger on a local sightseeing flight.
During the takeoff phase, the pilot performed an air taxiing maneuver at an altitude of approximately 15 to 20 feet. While attempting to re-establish a hover to prepare for departure, the helicopter experienced a sudden descent. The right landing skid struck the ground, causing the aircraft to roll onto its right side. The impact caused the main rotor blades to strike the ground, leading to the engine stalling and the separation of the main rotor driveshaft and pylon from the fuselage. The pilot sustained a minor wrist injury, and while the passenger was shaken, no other injuries were reported. There was no fire, though fuel was found leaking from the aircraft upon the arrival of emergency services.
The investigation
The AAIU investigation examined the flight conditions, the aircraft's mechanical state, and the terrain. The aircraft was found to be within weight and center of gravity limits, and there were no recorded technical defects or malfunctions prior to the impact. The investigation focused on the pilot's maneuvers and the environmental factors at the landing site.
Investigators noted that the pilot was maneuvering with the nose out of the wind. The terrain consisted of deep, clumpy grassland, which was identified as a significant factor in the aircraft's movement during the incident.
Findings
- The helicopter was maneuvering in a nose-out-of-wind condition with a downwind component.
- The pilot did not sufficiently respond to the increased power requirements needed during this maneuver, leading to an unplanned descent.
- The right landing skid became a pivot point due to the deep, clumpy grass, initiating a dynamic rollover.
- The pilot's response to the developing roll was inadequate to prevent the aircraft from reaching its critical rollover angle.