What happened
A flight involving a single occupant ended in a fatal accident within the Sierra Nevada Mountains. The pilot-owner had planned to fly over a glacier situated near the base of a 14,000-foot mountain, specifically located at the head of a box canyon at approximately 12,000 feet MSL. Observers on the ground noted the aircraft entering the canyon area.
As the aircraft reached the vicinity of the glacier, it began an attempt to reverse its direction. During this maneuvering phase, the aircraft experienced an aerodynamic stall and entered a rapid descent. The plane struck rocky, 40-degree upsloping terrain, which resulted in a post-impact fire. There was one fatality involving the pilot.
Findings
Investigations into the accident identified several contributing factors related to the pilot's actions and the environment. The aircraft was operating in a high-altitude area characterized by difficult terrain conditions, specifically a blind box canyon.
Key findings include:
- The pilot failed to maintain an adequate altitude for the terrain.
- There was a delayed decision to reverse course, which placed the aircraft in a precarious position.
- The accident was precipitated by an inadvertent stall during the turn.
- Improper in-flight planning and decision-making by the pilot in command were primary factors in the loss of control.