Accident Overview
A certified flight instructor (CFI) was providing helicopter flight instruction to an experienced airplane pilot who had accumulated approximately 2 hours of helicopter flight time. The accident occurred while the student pilot was hovering the helicopter oriented into the wind.
Sequence of Events
During the hover, the student allowed the rotor RPM to decrease. As the helicopter began turning left, the CFI assumed control but was unable to restore rotor RPM. The helicopter continued its left turn, prompting the CFI to execute a downwind emergency running landing onto soft, muddy turf.
After a ground run of approximately 15 to 20 feet, the helicopter started turning right. The skids dug into the soft turf, causing the helicopter to roll 90 degrees onto its left side. Both main rotor blades struck the terrain.
Damage
The helicopter sustained substantial damage to the main rotor system, transmission, tail rotor, tail boom, and fuselage.
Examination
A postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The CFI reported that he had been too slow in taking remedial action.