Robinson Helicopter Company R44 II N44KY accident near Las Vegas, Nevada

Probable cause

The pilot’s loss of helicopter control after the door opened during takeoff. Contributing to the accident was the pilot’s failure to confirm that the door was properly closed before departure.

NTSB analysis

Just after takeoff on an air tour flight, the pilot’s door opened abruptly as the helicopter accelerated through effective translational lift. The sudden wind startled the pilot, who released the collective with his left hand and reached across his body to close the door, inadvertently applying right cyclic. The helicopter descended, the right skid contacted the ground, and the helicopter entered a dynamic rollover, resulting in substantial damage. The pilot was uninjured, and the two passengers sustained minor injuries.

The pilot thought the door was latched before departure, and postaccident photographs showed the latch handle in the fully aft, down, and locked position. However, fresh paint scratches and dents around the latch receptacles were consistent with the horizontal and vertical latch pins being extended but not captured in their respective holes in the door frame. It is, therefore, possible that the pilot engaged the door latches before the door had fully closed, allowing it to open under aerodynamic loads as airspeed increased.

The circumstances of this event would have resulted in a strong startle response. Such an unexpected and forceful sensory event can momentarily override trained responses, leading to instinctive action. In this case, the pilot reacted reflexively to the perceived immediate threat by attempting to close the door, which resulted in loss of aircraft control.

A safety notice issued by the helicopter manufacturer cautions that cockpit distractions, including an open door, can lead to a loss of aircraft control and advises pilots to land rather than attempt to close a door in flight.

Text from the NTSB. Open the NTSB docket for WPR25LA110 for the full record.