What happened
On 1 August 2014, a Robinson R44 Raven I, registration G-OAJC, was conducting a private flight from Roscrea, Co. Tipperary, to an agricultural field near Kinnitty, Co. Offaly. The pilot intended to land in a field that had been pre-arranged for use, with the expectation that a ground person would be present to guide the approach to a safe landing spot.
As the pilot approached the field, they noted that the initial intended landing area contained tall grass, which posed a fire risk from the engine exhaust. To avoid this, the pilot began to hover-taxi toward a different corner of the field. During this maneuver, at an altitude of approximately eight feet, the main rotor blades made contact with telephone wires stretching from a roadside pole to a nearby schoolhouse. The impact caused the blades to disintegrate, sending large fragments across the road and causing the helicopter to spin and tumble into the field. The pilot, who was wearing a safety harness, managed to exit the aircraft through the rear passenger door. There were no injuries to the crew, and no fire occurred, though the aircraft was destroyed.
The investigation
The AAIU examined the circumstances of the wire strike, noting that the pilot was unfamiliar with this specific landing site. The investigation established that while the pilot had arranged for a person to be in the field to assist with the landing, no such person was present upon arrival. The investigators also analyzed the visual challenges associated with overhead wires, noting that such obstacles are notoriously difficult to detect due to human physiological limitations and background camouflage, especially when viewed against complex landscapes like trees and hills.
Findings
- The primary cause of the accident was the contact between the main rotor blades and telephone wires.
- The pilot lacked familiarity with the landing location.
- The absence of a ground person to indicate the landing area deprived the pilot of a critical safety resource.
- The flight was conducted in daylight under Visual Meteorological Conditions (VMC).