13-Nov-2012 Source: ATSB
The ATSB’s investigation into a wirestrike accident highlights the importance of a proper reconnaissance when flying in a wire environment and remaining focused only on operational tasks.
On 12 June 2012, a Robinson Helicopter Company R44 Raven 1 helicopter departed Moorabbin Airport, Victoria with one person on board to conduct a private flight to a property at Moolort, Victoria.
During the flight, the pilot decided to check on the progress of a bore under construction about 2 km west of his intended destination. The pilot landed at the bore site and, after a short time on the ground, decided to depart in the same direction as his approach.
As the helicopter transitioned from the hover to forward flight, the pilot saw a single strand powerline directly ahead. There was no time to avoid the wire and the helicopter struck the wire on the middle of the main rotor mast. The helicopter swung upwards on the wire and the pilot remembered seeing the sky before the wire broke, releasing the helicopter.
The pilot had limited control and was able to change the attitude to remain relatively straight and level until the helicopter landed heavily. The pilot was not injured, however the helicopter sustained serious damage.
The pilot reported that he had been focused on avoiding the main powerline and had not seen the second powerline during his scans of the area on arrival or prior to departure.
The accident highlights the importance of a proper reconnaissance when flying in a wire environment and remaining focused only on operational tasks. The pilot’s reaction to the wirestrike, which was to continue to fly the aircraft to the ground, assisted him to land without injury.
ATSB research has found that wirestrikes are the third most prevalent cause of fatal accidents in private flying operations. Research into aerial agriculture accidents found that wirestrikes occurred even when pilots knew the location of wires. Although this accident was not related to agricultural operations, the research found that focusing only on operational tasks while flying was an important habit to develop.