Robinson R22-Beta, VH-JNT, Coolangatta Aerodrome, Queensland, on 16 July 1990

Circumstances:

The student helicopter pilot was at an early stage of his training, however, he was a very experienced fixed-wing pilot. Before conducting some circuits, he was given practice in hovering. After this the instructor took over to demonstrate the manoeuvrability of the helicopter with the rotor disc steady. During this hovering the height increased to about 30 feet before the aircraft began to spin rapidly in an anticlockwise direction and dive towards the ground. The low rotor rpm warnings sounded during the descent. Impact evidence showed that the helicopter had struck the ground at a high rate of descent while travelling forward slowly. No signs of engine malfunction were found.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. The instructor did not maintain directional control of the aircraft.

2. The instructor did not maintain adequate rotor rpm.

3. The instructor was operating outside the safe flight envelope.