Piper PA-12 N7243V accident near Centerville, Washington

Probable cause

A loss of engine power due to carburetor icing conditions and the failure of the pilot to use the correct amount of carburetor heat for the existing conditions.

NTSB analysis

The pilot reported that he was maneuvering the airplane when the engine lost power. He stated that the carburetor heat was on at the time. The pilot reported that he attempted to regain power; however, the engine did not respond and the airplane subsequently collided with terrain in a nose-low attitude. The airplane nosed over and sustained substantial damage to the firewall and empennage. Post accident examination of the engine by a certified airframe and powerplant mechanic revealed no mechanical anomalies with the engine. Trace amounts of water were noted in the carburetor's accelerator pump during the examination. Data taken from a carburetor icing probability chart showed that the known temperature conditions were favorable for "icing" at "glide and cruise power" settings.

Text from the NTSB. Open the NTSB docket for SEA08LA063 for the full record.