Amateur-built T-18 N467JF accident near Willcox, Arizona

Probable cause

The pilot’s failure to maintain sufficient airspeed during a steep turn and at a low altitude in the traffic pattern, which resulted in an aerodynamic stall.

NTSB analysis

The airplane was observed in the traffic pattern, about 500 feet above ground level, when it made a steep left turn to enter the downwind leg. The turn continued as the airplane entered a left descending spiral until it impacted the ground in a nose-low attitude. Postaccident examination of the airframe and engine revealed no evidence of a mechanical malfunction or failure that would have precluded normal operation.

The Pilot Operating Handbook for the airplane indicated that the airplane has an abrupt stall with a tendency to drop a wing, especially if the airplane is in an uncoordinated turn during the stall. There is very little warning preceding the stall. Stall recovery can be quickly affected by releasing back pressure on the stick; however, a secondary stall may occur if the stick is brought back abruptly after recovery without sufficient airspeed. It is likely that during the initial steep turn, the airplane entered an aerodynamic stall from which the pilot was unable to recover at the low altitude.

Text from the NTSB. Open the NTSB docket for WPR10LA429 for the full record.