Cessna A188-A1, VH-KVM, 5 kilometres NE of MacAlister QLD, 11 January 1989

The pilot reported that a single power line was strung diagonally across the treatment area. A number of runs had been conducted under the wire. At about the mid-span of the wire between the supporting poles, the aircraft struck the wire. The wire deflector failed, allowing the wire to slip between the fin and rudder. The mass balance and the top of the rudder were severed, but the pilot maintained control and subsequently landed without further incident.