What happened
A commercial pilot and a pilot-rated passenger were conducting flight maneuvers within a rock quarry. The crew was practicing a pinnacle approach, which involves transitioning the aircraft into a hover over a specific point.
During the transition to a hover, the helicopter continued to settle toward the terrain. As the aircraft descended, the left skid made contact with the top of a gravel pile. In an attempt to recover, the pilot applied full collective and left cyclic input; however, these actions produced no notable response from the aircraft. Consequently, the helicopter continued to roll to the right and moved down the embankment.
The pilot reported that the accident was a dynamic rollover.
The investigation
An examination of the helicopter and its associated system components was conducted following the accident. The inspection revealed no evidence of any mechanical malfunction or failure.