What happened
During a flight demonstration for an FAA inspector, a pilot applicant was performing a maneuver simulating a power failure from a two-foot hover. During this procedure, the pilot lost control of the helicopter. The aircraft drifted toward the rear and to the left before impacting the ground. Upon impact, the helicopter rolled onto its left side. An FAA inspector on board attempted to recover the aircraft, but these efforts were unsuccessful.
Findings
The investigation noted that common errors during power failure simulations in a hover include failing to use sufficient anti-torque pedal when reducing power, failing to stop all sideward or backward movement before touchdown, and failing to apply up-collective pitch properly. Such errors can result in a hard touchdown or an unlevel attitude. Additionally, the aircraft is susceptible to dynamic rollover during lift-off; if a factor causes the helicopter to pivot around a skid until it reaches its critical rollover angle, main rotor thrust will continue the roll, making recovery impossible regardless of cyclic corrections.