What happened
On March 30, 2024, at approximately 11:55 local time, a Robinson R44 II, registration EC-LYD, was undergoing engine start-up procedures at the Barcelona Port Heliport (LEPB). The aircraft had previously completed a tourist flight earlier that morning and was being prepared for a subsequent mission.
During the pre-flight checklist, specifically at the moment the pilot applied throttle, the helicopter underwent a rapid leftward rotation. The aircraft completed two full revolutions to the left, tilting forward and striking the helipad surface. The impact caused the tail cone to fracture and the tail rotor to detach, while also causing significant damage to the main rotor blades and the fuselage. The pilot, who was the sole occupant, was uninjured and managed to shut down the engine by cutting the mixture.
The investigation
Investigators examined the wreckage and reviewed surveillance footage from the heliport. The inspection of the Robinson R44 II revealed no mechanical deficiencies in the tail rotor controls or any pedal jams. However, the investigation noted that the throttle was found in the maximum power position and the left pedal was fully engaged following the event.
Surveillance video analysis showed the pilot's physical posture immediately before the rotation; the pilot's left leg was extended with the foot appearing to be on the left pedal, while the right foot was resting on the cabin floor. A witness also reported hearing the engine being revved to high RPMs during the incident. The investigation also considered meteorological conditions, which were found to be stable and not a contributing factor.
Findings
- The primary cause of the accident was the loss of control of the aircraft during the engine start-up sequence.
- It is highly probable that the rapid application of throttle, combined with excessive left pedal input, induced a sudden torque-related rotation that the pilot could not counteract.
- The pilot's physical position, with the right foot not on the control pedal, likely prevented an immediate corrective input to the right pedal.
- The aircraft sustained substantial damage to the tail cone, main rotor, and fuselage.
- There were no injuries to the pilot or any other persons.