Accident Sequence
According to statements from both pilots, the instructor conducted a high reconnaissance of a ridgeline before setting the helicopter up for a practice pinnacle approach. At approximately 500 feet above the ridge, the instructor turned the controls over to the student.
Shortly after the approach was initiated, the instructor observed evidence of strong surface winds and ordered a go-around. Both pilots stated that as the go-around began, the low rotor rpm warning horn activated. The instructor reported attempting to regain rotor rpm and accelerate the helicopter. However, they were "hit by a very strong downdraft that forced us down to the surface."
The instructor then lowered the nose in an attempt to fly away from the ridgeline. The helicopter settled into the brush on the ridge and subsequently rolled over.