What happened
During a night departure under moonless conditions, the aircraft began a right-hand turn shortly after leaving the airport. The flight took place over remote terrain characterized by a lack of ground-based lighting and few external visual references. As the aircraft executed the turn, the bank angle increased significantly, eventually leading to a high-energy, low-angle impact with the ground. The wreckage was located approximately one mile from the airport, positioned in a manner suggesting the aircraft had turned roughly 180 degrees to the right after takeoff.
It is believed the pilot initiated this turn to navigate toward a navigational aid situated southwest of the airport, likely attempting to avoid terrain-induced turbulence and downdrafts caused by a nearby mountain range. At the time of the accident, weather reports noted strong winds gusting from the northeast.
Findings
Investigation of the wreckage showed no evidence of mechanical failure or malfunctions that would have prevented the aircraft from operating normally. Instead, the evidence suggests the pilot experienced spatial disorientation during the maneuver. The lack of a natural horizon and minimal visual cues, combined with the task of engaging the autopilot from the center console, likely reduced the pilot's awareness of the aircraft's attitude and altitude.
Several factors contributed to the loss of situational awareness:
- The presence of gusting winds and the lack of visual references during a night departure.
- The pilot's focus on secondary tasks, such as managing the autopilot system.
- The presence of therapeutic levels of doxylamine, a sedating antihistamine, in the pilot's system, which likely contributed to the onset of disorientation.
While the pilot was suffering from symptoms of an upper respiratory infection, the investigation could not definitively state how these symptoms impacted flight performance, though the sedative effects of the antihistamine were a significant factor.