NTSB Identification: ERA11LA409
14 CFR Part 91: General Aviation
Accident occurred Wednesday, July 20, 2011 in Dayton, NJ
Probable Cause Approval Date: 04/02/2012
Aircraft: ROBINSON HELICOPTER R22 BETA, registration: N83509
Injuries: 2 Serious.
NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.
The pilot slowed the helicopter to an out-of-ground-effect hover at an altitude of 400 to 500 feet above ground level (agl) while performing a photography mission. The photographer asked for a different vantage point; as the pilot explained that wind and high power demands would prevent him from accommodating the request, the helicopter began to "settle with power." The pilot attempted to arrest the descent with a reduction of power and a forward cyclic input. As the pilot took the corrective action, the helicopter yawed to the right and began to rotate around the main rotor mast. He reduced the throttle to idle to arrest the spin, and the yaw rate slowed. However, the spin continued as the helicopter descended through about 250 feet agl. The pilot stated that the helicopter was still spinning when it struck the ground upright. Review of an audio recording from a video camera aboard the helicopter indicated that the low rotor rpm audio alarm was on during the final 7 seconds of the flight. A witness reported that the engine ran "fine" and "perfectly" all the way to ground contact.
Examination of the wreckage revealed no evidence of pre-impact mechanical malfunctions or failures that would have precluded normal operation of the helicopter. The helicopter was operating in a high-power, low-airspeed condition that required the pilot to be especially aware of wind direction in order to avoid tailwinds, which can result in a loss of control due to settling with power and/or a loss of tail rotor effectiveness. Although the pilot’s comment to the photographer indicated that he was concerned about the wind angle, it is likely that he did not maintain a nose-into-the-wind position. When the helicopter began to settle with power, the rotor rpm dropped, and the tail rotor lost effectiveness. There was insufficient altitude for the pilot to affect a recovery before the helicopter impacted the ground.
The National Transportation Safety Board determines the probable cause(s) of this accident to be: The pilot's inadequate compensation for wind during an out-of-ground-effect hover, which resulted in a loss of control due to settling with power and loss of tail rotor effectiveness. Full narrative available
Index for Jul2011 | Index of months