What happened
During a flight training session, a certified flight instructor and a student were performing a practice autorotation. During the maneuver, the instructor determined that the aircraft would not be able to clear the trees located at the edge of the landing area.
The instructor attempted to take control of the helicopter and apply power to avoid the obstacles. However, he encountered resistance in the throttle system because the student did not relinquish control of the aircraft. In an attempt to clear the trees, the instructor may have pulled some collective and then flared the helicopter. The aircraft subsequently impacted the ground in a level attitude before coming to rest on its left side.
Findings
- The helicopter sustained damage during the impact.
- Resistance in the throttle system prevented the application of power due to the student's failure to relinquish control.