Summary
A helicopter engaged in power line construction in mountainous terrain struck an 80-foot metal pole during a maneuver to position a traveler, resulting in a dynamic rollover and subsequent ground impact. The accident occurred as the aircraft approached pole number 89 to straighten a traveler, a device used in line-pull operations.
Accident Details
According to witnesses, the helicopter initially approached the pole from the upwind side to straighten the traveler. After aligning the traveler and moving away, the rotor wash caused the traveler to shift out of position again. The helicopter then reapproached the pole at a higher speed than before. During this second approach, the helicopter's skid contacted the pole approximately 2 feet below its top. The impact caused the helicopter to dynamically roll over the top of the pole. As the pole entered the pilot's doorway, the pilot released all controls and braced himself against the pole. The helicopter then severed three main conductors before colliding with the ground.
Aftermath
The helicopter was operating with a pilot and a passenger seated in the rear. The passenger's role involved physically kicking travelers into proper position at the top of the pole to establish correct tension for line pulling. No information about injuries, fatalities, or damage extent was provided in the source.