Amateur-built W10 N129WT accident near West Livingston, Texas

Probable cause

A partial loss of engine power due to carburetor ice.

NTSB analysis

About 30 minutes after departing on a cross-country flight, the pilot heard the engine “misfire,” but observed that all engine instruments and temperatures appeared normal. The engine misfired again, and he decided to return to his departure airport. A few minutes later, the engine lost partial power. Unable to maintain altitude, the pilot elected to divert to a nearby airport. During the landing roll, the airplane exited the runway surface, nosed over, and came to rest inverted.

The airplane sustained substantial damage to the vertical stabilizer and rudder. Postaccident examination of the airframe and engine revealed no evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation.

Based on the reported weather conditions at the time of the partial power loss, the airplane was operating in conditions conducive to the formation of serious icing at glide power. The pilot reported that he applied carburetor heat and felt that application exacerbated the problem, so he turned off the carburetor heat and continued with the forced landing. It is likely the engine sustained a partial loss of engine power due to the formation of carburetor ice and that the pilot likely turned off the carburetor heat before the ice melted.

Text from the NTSB. Open the NTSB docket for CEN24LA301 for the full record.