Amateur-built Swift II N84NS accident near San Antonio, Texas

Probable cause

The pilot's failure to attain a proper pitch attitude and airspeed during initial climb, which resulted in an aerodynamic stall.

NTSB analysis

The airplane was climbing through about 50 to 75 feet above ground level when it suddenly rolled left. The pilot tried to counteract the roll, but the airplane was unresponsive to control inputs. The sudden roll followed by a lack of control authority was consistent with an aerodynamic stall as the airplane transitioned from the aerodynamic effects of flight near the ground. A stall progression near the ailerons would have affected control authority. A postaccident examination of the flight control system revealed no malfunctions or failures that would have precluded normal operation. It is likely that the pilot climbed too steeply after takeoff without attaining the proper airspeed.

Text from the NTSB. Open the NTSB docket for CEN13LA116 for the full record.