Robinson Helicopter Company R44 II N445AB accident near Indiana, Pennsylvania

Probable cause

The pilot's operation of the helicopter at a low-forward airspeed out of ground effect, which resulted in the helicopter’s loss of translational lift and tail rotor authority and the pilot’s subsequent loss of helicopter control.

NTSB analysis

The single-engine helicopter was operating in an urban area with a three-person film crew onboard who were following the movements of police vehicles. One of the passengers reported that, while following cars and filming them, the pilot turned the helicopter about 180 degrees while not moving in a forward direction. The helicopter then started bucking forward and backward and, at the same time, began to spin downward until it impacted a building. A witness reported that he saw the helicopter flying about 100 feet above ground level at a very slow rate of forward airspeed in a west-to-east pattern while making multiple passes. He said that the helicopter was making 180-degree flat turns (without a banking attitude). A few minutes later, he saw the helicopter flying in a northwesterly direction, enter what he believed to be a short sudden autorotation, and then lose altitude. Postaccident examination of the helicopter did not reveal any preexisting mechanical anomalies with the airframe, drive system, or engine that could have contributed to the accident.

Two segments of video were recovered from one of the video cameras onboard the helicopter. The second segment was 73 seconds long and contained the final moments of the accident flight. Sixty-one seconds into the segment, the camera zoomed out, and the helicopter began a right rotation, before which, there was very little evidence of forward airspeed. Between 61 and 73 seconds, the helicopter completed two full right rotations. At 63 seconds, the helicopter pitched nose down, and, at 67 seconds, it then returned to nose level and lost altitude. At 68 seconds, the helicopter pitched nose up for 3 seconds. At 71 seconds, it pitched further nose up and then completed a quarter of a rotation before the video ended. From 67 seconds to the end of the recording, the main rotor blades came into view, and rotor blur was visible. Given the witness and video evidence, the helicopter likely experienced a loss of translational lift and corresponding loss of sufficient tail rotor authority to maintain level flight because the pilot was operating the helicopter out of ground effect at a low forward airspeed.

In March 1999, Robinson Helicopter issued Safety Notice SN-34 to be included as a supplement in the R-44 Pilot Operating Handbook; a revision was issued in April 2009. The Safety Notice indicated, in part, that, "Aerial survey and photo flights should only be conducted by well trained, experienced pilots who…Have at least 500 hours pilot-in-command in helicopters and over 100 hours in the model flown." The accident pilot had about 388 hours of total helicopter flight time, including about 41 hours in the accident model helicopter.

Text from the NTSB. Open the NTSB docket for ERA11FA272 for the full record.