What happened
On May 18, 2014, at approximately 1600 MST, an American Eurocopter AS350B3, registration N840PA, experienced a fatal accident at the Ramada landing site near the bottom of the Grand Canyon. The aircraft was being operated by Papillon Airways Inc. for a repositioning flight from Grand Canyon West Airport (1G4).
Prior to landing, the pilot notified ground personnel that he intended to perform a "fluid level check." According to company interviews, this term was frequently used by pilots as a code for exiting the aircraft to relieve themselves without shutting down the engine.
After touching down at the North Ramada/LVH Pad, the pilot tightened the cyclic friction and adjusted the engine to flight idle. The pilot then removed his headset, placed earplugs in his ears, and exited the aircraft. During the period the pilot was outside the cockpit, the helicopter experienced increased airframe buffeting due to a crosswind. The aircraft subsequently began to pitch nose down, roll to the right, and yaw to the left. The helicopter continued this motion until the main rotor blades impacted the ground, causing the aircraft to roll over. The pilot sustained 1 fatal injury after being struck by the rotor blades.
The investigation
Investigators examined the wreckage at the landing site, finding the helicopter resting on its right side. The investigation team found no abnormalities in the airframe, engine systems, or flight control systems. The aircraft was equipped with an Appareo Vision 1000 cockpit imaging and flight data monitoring device, which provided critical video and engine data.
Analysis of the cockpit video and engine data recorder revealed that while the pilot had previously performed similar maneuvers at ground idle, the engine in this instance was at flight idle. The data showed that the collective position increased and the rotor RPM declined sharply shortly before the aircraft's upset. The investigation also noted that both main cabin doors were found open at the scene.
Findings
- The pilot exited the helicopter while the engine was still running.
- The flight controls were not properly secured before the pilot exited the aircraft.
- The engine was operating at flight idle rather than ground idle at the time of the accident.
- A company culture existed where pilots used "fluid checks" as a euphemism for exiting the aircraft to relieve themselves without shutting down the engine.
- The aircraft was subjected to a buffeting crosswind during the event.