Incident Overview
A helicopter experienced a hard landing during a practice touchdown autorotation (auto) while operating in closed traffic at an airport. The aircraft was conducting training maneuvers in a landing area adjacent to the runway. Another helicopter was also in closed traffic practicing the same type of approach and landing.
Sequence of Events
The private pilot initiated the autorotation. The certified flight instructor (CFI) then assumed command because he assessed that the helicopter would not clear a perimeter fence located short of the intended touchdown point. The CFI applied collective pitch to extend the glide path over the fence. According to the private pilot, the rotor RPM subsequently depleted, and the CFI did not flare the helicopter sufficiently to regain rotor RPM or reduce ground speed. The helicopter landed hard and bounced.
Examination and Findings
Neither the private pilot nor the CFI reported any mechanical failures or malfunctions with the helicopter. No other issues were identified during the post-incident inspection.
Conclusion
The incident involved a hard landing during a training autorotation, with the CFI taking corrective action to avoid a fence but not executing a flare adequate to preserve rotor RPM or control descent rate.