The aircraft had been engaged in spraying cotton fields in generally turbulent flying conditions. Power lines crossed one end of the area at an angle of about 20 degrees to the direction of the swath runs. At their lowest point, these wires were about 10 metres above the ground. The pilot reported that as he approached the power lines, intending to fly underneath at the lowest point, the aircraft ballooned upwards in turbulence. Despite corrective action the cockpit mounted wire deflector struck the lines. The deflector was broken and much of the fin and rudder was torn from the aircraft, which subsequently impacted the ground about 800 metres from the power line.