What happened
On March 5, 2015, a Robinson R44 helicopter, registration F-GOLT, was performing a general aviation flight from Mâcon Charnay to the Beaune Challanges aerodrome. Upon arrival, the pilot attempted to land on a 5-meter square concrete pad located on a 10% slope.
As the aircraft touched down, only the front portion of the skids was resting on the concrete surface. After contact, the pilot reduced collective pitch. During this maneuver, the aircraft tilted backward and experienced a right yaw, causing the helicopter to lean heavily to the left. This movement caused the main rotor blades to strike the ground, subsequently severing the tail boom and the rear transmission. The aircraft came to rest on its left side, and while the three occupants sustained minor injuries, the helicopter was destroyed.
The investigation
The investigation focused on the aircraft's positioning on the landing pad and the pilot's control inputs. Investigators noted that the chosen landing area was elevated approximately 30 centimeters above the surrounding ground. The pilot, who had approximately 100 total flight hours, stated he was aware the aircraft was not centered on the pad but did not realize the skids were not fully supported by the concrete.
Meteorological data indicated wind speeds of approximately 12 knots, with potential gusts up to 25 knots. Analysis of the wreckage confirmed that the main rotor blades had struck the tail boom and rear transmission with enough force to sever them. The pilot noted that during the backward tilt, he may have applied abrupt cyclic and collective inputs as a reflex.
Findings
- The primary cause of the accident was the improper positioning of the skids on the landing pad, which created an unstable landing configuration.
- The decision to continue the landing while the aircraft was not fully supported by the concrete pad made the helicopter difficult to control.
- The pilot's likely abrupt application of collective and cyclic inputs during the backward tilt caused the rotor blades to flap, leading to the collision with the tail boom.