Mooney M20B N74786 accident near Animas, New Mexico

Probable cause

The pilot’s delayed use in the operation of carburetor heat which resulted in a loss of engine power due to carburetor icing.

NTSB analysis

During a night instrument flight rules cross-country flight, the airplane encountered weather that included clouds and icing conditions. Shortly thereafter, the engine began to run rough and lose power; radar contact was lost, and the airplane was located in mountainous terrain.

Postaccident examination of the airframe and engine revealed no mechanical anomalies that would have precluded normal operation.

Weather conditions reported at the time of the accident were conducive to the formation of serious carburetor icing at cruise power settings. The pilot reported that, during a climb into clouds, with the carburetor heat off, the engine began to run rough and was losing rpms before he applied carburetor heat. Therefore, it is likely that carburetor ice accumulated during the climb, which resulted in a partial loss of engine power.

Text from the NTSB. Open the NTSB docket for WPR21LA141 for the full record.