Cessna 150M N66786 accident near Sinton, Texas

Probable cause

The inadequate service and repair of the airplane's carburetor, which led to a partial loss of engine power during takeoff and resulted in a forced landing.

NTSB analysis

The commercial pilot reported that after conducting a touch-and-go landing, the airplane's engine experienced a partial loss of power near the end of the runway. The airplane was unable to gain altitude, so he landed in an open field. During the forced landing, the airplane's engine mount was bent. According to the pilot, the airplane's carburetor was full of carbon and that the exhaust pipe was black from carbon buildup. Although it is unlikely that the black material in the carburetor was carbon, the excessive buildup within the carburetor would have adversely affected the engine's performance. The pilot stated that the carburetor was unable to properly regulate the fuel/air mixture due to the excessive buildup, corrosion in and on the main nozzle, and basic wear and tear, which caused the engine to flood and experience a partial loss of engine power. A review of the airplane's maintenance logbook showed that the carburetor had not been rebuilt since it was installed in 1974, about 44 years before the accident. Thus, it is likely that inadequate service and repair of the airplane's carburetor led to partial loss of engine power.

Text from the NTSB. Open the NTSB docket for CEN18LA177 for the full record.