Accident Narrative
The pilot had fueled the airplane with auto gas 1 1/2 weeks prior to the accident. On the day of the accident, the fuel tanks were 3/4 full, and the temperature at the time of departure was 19 degrees Fahrenheit. After takeoff, the pilot climbed to between 150 and 200 feet above ground level to look for cows. Approximately 25 minutes into the flight, the engine RPM dropped by 300 RPM. The pilot then pushed the throttle fully forward, but the engine did not respond. He pulled the carburetor heat on, which caused the engine RPM to decrease by an additional 200 RPM. The pilot turned the airplane toward a stubble field. Despite his efforts, the airplane continued to lose altitude. He attempted to increase the RPMs but was unable to regain engine power. The pilot reported that a wind gust might have caught him and pulled the airplane to the ground. The airplane subsequently impacted the ground.
Post-Accident Examination
Following the accident, the spark plugs were removed and found to be worn and carbon fouled. The air intake filter was grimy. The fuel line to the carburetor had a small ice pellet formation, covering approximately one-fifth of the circumference of the metal neck where it flared into the carburetor B-nut. Additionally, the aircraft had not received an annual maintenance inspection.