What happened
Five minutes after departing, while flying at an altitude of 500 feet, the pilot heard a loud noise from the engine which resulted in a reduction in power. The pilot attempted to regain power by manipulating the carburetor heat control. Due to this partial loss of engine power, the pilot performed a precautionary landing at the first available site, a small private airstrip.
During the landing roll, the aircraft veered to the right. Although the pilot attempted to correct the course to the left, the airplane departed the runway and entered soft ground on the left side of the airstrip. The impact caused the aircraft to nose over onto its back. At the time of the accident, meteorological data from the nearest station indicated a temperature of 95 degrees Fahrenheit and a dew point of 60 degrees Fahrenheit.
The investigation
Under the supervision of an FAA inspector, an Airframe & Powerplant mechanic examined the engine and found no anomalies. The mechanic was able to start the engine and achieved 800-900 rpm before shutting it down because of vibrations caused by a bent propeller.