Accident Sequence
A flight instructor and a student were practicing 180-degree autorotation landings in a helicopter. During the training session, they climbed to 500 feet above ground level (agl) before initiating their final autorotation to the left. The student was at the controls and began a steeper turn in an attempt to reach the intended aiming spot. As a result, the helicopter entered a slight dive.
When the student rolled out to begin the flare, the helicopter was below 100 feet agl. At that point, the instructor took control of the helicopter. He pushed forward to level the helicopter, then rolled the throttle and attempted to pull up on the collective.
Impact and Damage
The helicopter struck the ground in a level attitude. Upon impact, it became airborne again. During the impact sequence, the tail boom was severed. The helicopter then spun three or four times before coming to rest on its left side.
Pilot Statement
According to the instructor, there was no mechanical malfunction with the helicopter.