On 23 February 2013, a Robinson R44 Raven I helicopter, registered VH-HGF, was engaged in agricultural operations in a paddock near Clarks Hill, Victoria. The pilot was the only person on board.
As the helicopter approached the paddock from the south, at 50 kt and at spray height, the pilot remembered a wire that extended halfway across the southern boundary of the paddock to a pump house. The pilot judged that it was too late to attempt to pull up over the wire and attempted to avoid the wire by flying underneath it. The vertical stabiliser contacted the wire and the tail rotor gearbox separated from the tail boom. The pilot was able to exit the helicopter with minor injuries however the helicopter was substantially damaged.
The practice within the aerial agricultural industry is to extensively pre-plan an application task that takes into account the specific hazards affecting an application. Any change from the previously planned application runs, including an unplanned change of direction has the potential to affect a pilot’s awareness of the relative position of previously known power lines and other hazards.