What happened
A flight was being conducted for the purpose of a new hire checkout. The crew intended to land at a specific location to retrieve a door that had detached from the aircraft during a flight the previous day.
During the approach, the pilot performed both high and low reconnaissance of the area to verify that the landing zone was clear of obstructions and to determine wind direction. Approximately 100 feet from the intended touchdown point, the wind shifted and became a tailwind. In an attempt to compensate for the resulting loss of altitude, the pilot increased power; however, the engine lacked sufficient power to maintain altitude.
While the helicopter remained controllable using full left rudder, the aircraft began to settle as both the engine and rotor RPM decayed. As the pilot attempted to fly downhill to regain RPM, he encountered resistance on the controls. At this time, the check pilot instructed the other pilot to verify his RPM and verbalized that he was taking flight control. The check pilot attempted a low RPM recovery by reducing the collective and rolling on the throttle, but noted the throttle was already in the full-on position. The check pilot then attempted to recover RPM by moving the collective up and down to clear the ridgeline. Despite these efforts, the helicopter continued to settle and landed hard, subsequently striking a tree and becoming inverted.
The investigation
The investigation found no discrepancies with the engine power.