Collision with terrain – Guimbal Cabri G2, VH-ZZT, Camden Airport, New South Wales, on 13 April 2012

On 13 April 2012, at about 1440 Eastern Standard Time, a Guimbal Helicopters Cabri G2 helicopter, registered VH-ZZT (ZZT), collided with terrain at Camden Airport, New South Wales. On board the helicopter was an instructor and a student.

The Guimbal Cabri G2 is a two-seat helicopter manufactured in France. It features a 7-bladed fenestron in place of a conventional tail rotor and a 3-bladed main rotor, which rotates clockwise when viewed from above. It received the European Aviation Safety Agency’s Type Certificate in December 2007.  ZZT was the first of the type to be registered in Australia.

The student was undergoing type endorsement training. The instructor simulated a jammed right yaw control pedal forward emergency in the hover.

The instructor then demonstrated a recovery procedure from the simulated emergency.  During the demonstration a rate of decent developed, which was assessed to be too fast.

The instructor attempted to abort the manoeuvre by increasing collective, applying full throttle to increase the rotor revolutions per minute and full right pedal to counteract the left yaw. The helicopter rotated to the left through several full rotations at an increasing rate.  The instructor was unable to recover the rotor RPM nor arrest the left yaw or left roll that developed.

The helicopter collided with terrain in a left skid-low, nose-high attitude.  The student suffered minor injuries and the helicopter was seriously damaged.

This accident highlights that different helicopter types have their own specific handling characteristics; and that pilots should be familiar with the emergency procedures prescribed in the flight manual and the immediate actions to be performed to ensure a successful outcome.

Aviation Short Investigation Bulletin - Issue 12