What happened
During a sightseeing excursion through a narrow canyon, the pilot performed tight, descending turns to allow passengers to photograph several black bears observed in the area. During these maneuvers, the aircraft's stall warning horn activated; however, the pilot proceeded with the turns. As the flight transitioned from the turns into an uphill climb within the valley, the aircraft was unable to sustain sufficient airspeed to clear the rising terrain.
The resulting loss of control led to a collision with the ground and a subsequent nose-over at an elevation of approximately 3,000 feet. The ambient temperature at the time of the accident was 62° F. There were six occupants on board the aircraft, all of whom sustained serious injuries.
Findings
Investigations into the accident identified several contributing factors related to the pilot's actions and environmental conditions:
- The pilot's attention was diverted from essential flight parameters during the maneuver.
- Inadequate preflight planning and preparation by the pilot in command.
- The aircraft experienced an inadvertent stall/mush condition.
- High density altitude conditions contributed to the difficulty of maintaining performance.
- The terrain characteristics, specifically the rising nature of the valley, made a proper climb rate impossible under the circumstances.