Amateur-built Classic Sport S-18 N216TB accident near Tea, South Dakota

Probable cause

A loss of engine power for undetermined reasons and the pilot's loss of airplane control, which led to an aerodynamic stall.

NTSB analysis

A witness reported that the pilot was flying a maintenance test flight because the airplane engine’s carburetor was replaced with a fuel injection system and a new air filter system was installed. The engine appeared to be developing full power during the takeoff roll. When the airplane was about 500 feet above ground level (agl), it made a left crosswind turn. The witness reported seeing a brief puff of black smoke coming from the engine exhaust. The airplane then entered a descending left turn before encountering a full stall about 100 to 150 feet agl. The airplane impacted a cornfield near the airport in about a 60- to 70-degree nose-down, inverted attitude. Postaccident inspection of the airframe revealed no preimpact anomalies. The inspection of the engine and fuel injection system revealed no preimpact anomalies; however, the mechanical fuel pump and both magnetos were broken by impact forces and could not be tested. No other anomalies were found with the airplane.

Text from the NTSB. Open the NTSB docket for CEN10LA429 for the full record.