Aviat A1 N137C accident near Ennis, Montana

Probable cause

The pilot's exceedance of the airplane's critical angle of attack while turning at low altitude, which resulted in an aerodynamic stall. Contributing to the accident was the pilot's distraction due to looking at wildlife.

NTSB analysis

The pilot reported that he was conducting an aerial survey to spot bears. After spotting bears, he flew multiple low-altitude passes to maintain sight of the bears. While maneuvering uphill at a low altitude, his attention was drawn to the bears and away from terrain. When he regained focus, he decided to turn the airplane right, away from rising terrain, but about 90º into the turn, the airplane descended and impacted terrain, and a postcrash fire ensued. The airplane sustained substantial damage to the wings and fuselage. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. The pilot added that he should have let the observer observe the bears during the low passes.

Text from the NTSB. Open the NTSB docket for GAA19CA432 for the full record.