On August 5, 1996, a Piper PA-12 (registration N2564M) was involved in an aviation accident near Astoria, OR. Investigators recorded the probable cause as: failure of the carburetor heat box flapper valve, and the resultant air flow restriction to the carburetor. A factor relating to the accident was: high vegetation in the area where the forced landing was executed. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
Aircraft experienced complete loss of engine power at 200 feet AGL during initial climb. Pilot executed forced landing in high vegetation, resulting in substantial damage. Inspection found carburetor heat box flapper valve broken and restricting airflow.
Incident Overview
During the initial climb after takeoff, at approximately 200 feet above ground level, the aircraft suffered a complete loss of engine power. Faced with this emergency, the pilot maneuvered the aircraft toward a forced landing. The touchdown occurred in an area covered with high vegetation. The forceful landing resulted in substantial damage to the aircraft.
Investigation Findings
A post-incident examination of the engine was conducted. Investigators discovered that the carburetor heat box flapper valve had separated from its mounting. This broken component was found to be obstructing the airflow within the carburetor throat. The restricted airflow was identified as the direct cause of the engine power loss.