Introduction
A helicopter was damaged when it struck the ground and rolled onto its left side during a demonstration of maneuvers over tall grass near a hill.
Event Details
The pilot reported that a tail wind of five to ten knots was present at the time of the accident. While operating at 110% torque, the pilot believed the helicopter's tail stinger struck the hill. The pilot stated that he over-controlled the collective when he reduced torque, causing the helicopter to descend rapidly and collide with the ground.
Pilot's Account
According to the pilot, the helicopter descended rapidly after he reduced the torque. It then struck the ground and rolled onto its left side. The pilot attributed the rapid collective reduction to strong emphasis during training from the manufacturer's instructor pilots, who had stressed the importance of staying below maximum torque. The pilot said that this emphasis resulted in his rapid reduction of the collective, leading to the hard collision with terrain.
Background
During training, the pilot had been instructed by manufacturer's instructor pilots who strongly emphasized the necessity of remaining below maximum torque. The pilot stated that this emphasis directly influenced his actions during the accident sequence.