Piper PA18 N726 accident near Wyndmere, North Dakota

Probable cause

The pilot's exceedance of the airplane's critical angle of attack during an uncoordinated turn while maneuvering at low altitude, which resulted in an aerodynamic stall.

NTSB analysis

The pilot reported that he was hired to conduct a predator control flight. He added that, after completing a right turn to the west, he initiated a climbing left turn to the east, and about 75 ft above ground level, the airplane "banked violently to the right and back to the left about two-three times," descended, and then impacted snow-covered ground.

The airplane sustained substantial damage to the right wing.

The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.

The hiring agency check pilot reported that, during a postaccident flight review with the accident pilot, the pilot did not apply rudder inputs during turns, which resulted in uncoordinated turns, similar to what occurred in this accident.

Text from the NTSB. Open the NTSB docket for GAA19CA158 for the full record.