Incident Overview
During a currency training flight involving two FAA inspectors, the helicopter experienced a hard landing while performing a practice power recovery autorotation. The pilot delayed in applying power and collective pitch, and upon ground contact, all engine instruments indicated normal operation with the engine RPM at idle. Additionally, the pilot failed to maintain adequate rotor RPM throughout the maneuver.
Sequence of Events
After the hard landing, an immediate inspection did not disclose any damage. However, upon the flight's return to Birmingham, substantial structural damage was noted in the right rear skid area. The damage was not apparent at the touchdown site but became evident later.
Damage Findings
Substantial structural damage was identified specifically in the right rear skid area of the helicopter. No other damage was reported. The helicopter had been operated without any prior indication of the extent of the damage until the post-flight inspection at Birmingham.