Summary
During a training flight focused on auto rotations with power recovery, the helicopter made a hard landing that resulted in substantial damage to the fuselage. The incident occurred during a descent from an auto rotation maneuver.
Narrative
The flight instructor reported that as the helicopter descended through approximately 40 feet, he instructed the student pilot to increase the landing flare and roll on throttle for power recovery. As the helicopter continued to quickly descend to about 8 feet, the crew raised the collective. The flight instructor noted resistance in the collective, and the rotor RPM began to decrease. He then attempted to roll on the throttle to restore RPM.
The flight instructor believed that the student had tensed up on both the throttle and the collective while trying to keep the helicopter level and cushion the landing. The student pilot reported that, in hindsight, he was pulling up on the collective but his hand (wrist) was locked, which prevented the governor from rolling on and increasing power.
Damage
The hard landing resulted in substantial damage to the fuselage. No other damage was reported.
Mechanical Status
The flight instructor reported that there were no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation.