Incident Overview
A public-use instructional flight ended with a hard landing while the crew was practicing autorotations. The helicopter impacted terrain after the maneuver was initiated.
Pilot Statements
The private pilot reported that the certified flight instructor (CFI) retarded the throttle, prompting her to enter an autorotation. The CFI then advanced the throttle to the full-on position. The helicopter was subsequently leveled and collective pitch was applied. The helicopter landed hard.
The CFI stated that he observed an excessive sink rate during the descent. He applied throttle but received no response. He used cyclic control inputs to assist the private pilot in leveling the helicopter and collective control to cushion the landing.
Sequence of Events
During the autorotation practice, the CFI reduced engine power. After the entry, he returned the throttle to the full-on position. The helicopter was then leveled and collective was raised. The landing was hard, with the CFI noting a lack of engine response when he attempted to add power.
Conclusion
The hard landing occurred during an instructional autorotation. The CFI's efforts to mitigate the sink rate and cushion the landing were unable to prevent the hard impact.