Primary finding
Probable cause
The pilot's failure to maintain clearance from wires during an agricultural application flight.
Investigator assessment
Analysis narrative
The pilot reported that, during the agricultural application flight into rising terrain, he saw power wires. He said he "lowered the collective…slightly nose down" to attempt to go under the wires, but the helicopter struck the wires, rolled right, and started descending. The helicopter touched down, bounced, spun right, and then rolled onto its left side. The helicopter sustained substantial damage to the tail rotor drive system. The 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 helicopter pilot reported that, during the aerial application flight into rising terrain, he saw the powerline wires when the airspeed was about 40 knots. The helicopter struck the wires and rolled to the right, and subsequently descended. The helicopter touched down upright and bounced. The nose of the helicopter spun to the right and the right skid struck the ground. The helicopter rolled onto its left side and stopped. The helicopter sustained substantial damage to the tail rotor drive system. The pilot reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation.