Incident Overview
A flight destined for a town in a mountain valley encountered an in-flight upset after a sightseeing maneuver. The pilot had been flying on the southwest side of the valley and then headed north toward the town where he intended to land and spend the night.
Sequence of Events
Approximately 3 miles south of the town, the aircraft flew over a small ridge, placing it about 500 feet above ground level (AGL). The passenger commented on some corrals on the ground below, prompting the pilot to execute a 360-degree turn to view the area. During the turn, the pilot noted a slight increase in airspeed. As the aircraft rolled out onto a northerly heading, it suddenly felt as if it stalled and entered a rapid descent.
Pilot Response and Landing
The pilot lowered the nose and flared as the aircraft approached the ground. The aircraft landed flat, and the impact broke off the landing gear. Shortly after ground contact, a large cloud moved overhead, bringing lightning and heavy rain with very gusty surface winds.
Mechanical and Environmental Factors
The pilot stated that there were no mechanical malfunctions or failures prior to ground contact. Based on pressure altitude and temperature recorded at a weather reporting station 15 miles east of the accident site, the density altitude was calculated to be about 7,500 feet.
Conclusion
The event involved a stall-like upset during a low-altitude turn, followed by a hard landing that resulted in landing gear failure. No mechanical issues were reported.