Primary finding
Probable cause
The pilot’s failure to maintain adequate clearance from transmission power wires, which resulted in a tail rotor strike.
Investigator assessment
Analysis narrative
The chief pilot reported that, while the pilot was working on transmission power wires, the pilot maneuvered the helicopter closer to the wires to give a better position for the other crewmember. He added that the pilot heard a noise and felt a vibration from the tail section. The pilot moved away from the wires, noticed no abnormality of flight, and returned to the landing zone without further incident. Postaccident examination revealed that the helicopter sustained substantial damage to the tail rotor. The chief pilot reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation.
Source record
Factual narrative
The Chief Pilot reported that, while working on transmission power wires, the pilot maneuvered the helicopter closer to the wires to give a better position for the other crew member. He added that the pilot heard a noise and felt a vibration from the tail section. The pilot moved away from the wires, noticed no abnormality of flight, and returned to the landing zone without further incident. Postaccident examination revealed that the helicopter sustained substantial damage to the tail rotor. The Chief Pilot reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation.