Pre-Flight Planning
The pilot obtained hazard information from the property owner, who was unaware of a distribution powerline strung across the valley. Unlike some other states, readily usable electricity network maps were not available to assist the pilot's planning. These maps can provide valuable safety information to help identify hazards such as wires and poles. The pilot had previously seen low powerlines at a neighboring property during road visits, but that knowledge did not help identify the airborne wire hazard.
Departure and Wire Strike
The pilot elected to depart in the same direction as the landing approach, meaning the powerline was not overflown during arrival. No aerial reconnaissance of the take-off and departure track was conducted, which could have helped identify the powerline's poles and wires. Consequently, the pilot was unaware of the distribution powerline across the intended flight path. The helicopter struck the powerline about 400 meters from the take-off site during a shallow departure climb down the valley.
Hazard Awareness
Powerlines at significant heights above ground are common in valleys, as they are often strung across them to reduce the number of poles and vegetation clearing. The pilot reported not expecting any powerline at a height exceeding 150 feet above ground level. The pole on the hill was visible from the take-off site, but the pilot did not see it. The powerline wires were inherently difficult to sight and had no markers to increase visibility.
The circumstances highlight that wirestrike prevention can be enhanced through a combination of available wire location information, wire marking, and avoidance of unnecessary low flying—especially below the height of surrounding higher terrain where wire spans may be present.