Overview
On 6 September 2021 at 14:15 local time, an Airbus Helicopters AS350 B1 (registration LN-ORJ) operated by Heli-Team AS became entangled in an overhead power line spanning the Gullesfjord in Kvæfjord municipality, Troms county. The helicopter was conducting a line inspection for Vesterålskraft Nett AS (now Vestall AS). There were four people on board: the commander and three power company personnel. No injuries or environmental damage occurred.
Sequence of Events
The helicopter had been inspecting a 22-kV power line that day. Earlier, it had crossed the Gullesfjord north of the power line, then flew to Gullesholm and followed the line south toward Tverrbakkhella. At Tverrbakktinden, the mountain rises in a south-eastern direction. Power supply fitters on board identified a fault in a crossarm of an electricity pole and wished to return to document it. The commander planned a right-hand turn. Without realizing, he flew the helicopter under the overhead power line crossing the fjord. He initiated an ascending right-hand turn. After approximately 180 degrees of the turn, the helicopter began descending toward the fault location. At that moment, the commander became aware of the power line and pulled the collective pitch control hard, but a collision was inevitable. The helicopter caught the middle of the three cables, lifting it over the northernmost cable. The helicopter was briefly stuck before the rotor blade cut the cable.
Damage and Injuries
The helicopter was damaged in the impact, but the rotor blade was not critically damaged and the flight controls remained intact. There were no personal injuries. The commander performed a controlled emergency landing afterward. The power line was cut.
Investigation
The Norwegian Safety Investigation Authority (NSIA) classified the event as a serious aviation incident. The NSIA’s investigation found that the safe job analysis had identified crossing power lines as the main risk. The power line that was cut had already been inspected by the commander that day. The NSIA expressed the opinion that inadequate preparation by the helicopter operator, planning and performance, the poor visibility of the line, and the pilot’s limited experience of line inspections and high mental workload explained why the pilot did not become aware of the power line until a collision was inevitable. The NSIA also noted that only coincidence prevented the incident from becoming a fatal accident and that the commander demonstrated good airmanship after the rotor blade cut the cable.