Accident Details
A helicopter accident occurred when a pilot applicant was demonstrating a simulated power failure from a two-foot hover to an FAA inspector. During the demonstration, the pilot lost control of the helicopter. The helicopter drifted aft and to the left before impacting the ground and rolling onto its left side. The FAA inspector attempted to recover the helicopter but was unsuccessful.
Common Errors in Power Failure Execution
According to the FAA Rotorcraft Flying Handbook, common errors when executing a power failure in a hover include:
- Failing to use sufficient proper antitorque pedal when power is reduced.
- Failing to stop all sideward and backward movement prior to touchdown.
- Failing to apply up-collective pitch properly, resulting in a hard touchdown.
- Failing to touch down at a level attitude.
- Not rolling the throttle completely to idle.
Dynamic Rollover Phenomenon
The handbook also notes that a helicopter is susceptible to a lateral rolling tendency, called dynamic rollover, when lifting off of the surface. For dynamic rollover to occur, some factor must first cause the helicopter to roll or pivot around a skid or landing gear wheel until its critical rollover angle is reached. Beyond this point, main rotor thrust continues the roll and recovery is impossible. If the critical angle is exceeded, the helicopter rolls on its side regardless of cyclic corrections.
No additional details about the specific conditions of this accident, such as the helicopter model, registration, operator, or date, were provided in the source.