Incident Overview
A Cessna 152 experienced a partial loss of power while on a night visual flight rules (VFR) pleasure flight, resulting in a forced landing to a rough plowed field where the aircraft nosed over during the landing roll.
Flight Details
The pilot, accompanied by his girlfriend, had offered to demonstrate negative gravity. During the flight, he slowed the aircraft and climbed to approximately 2,600 feet above mean sea level (MSL). While recovering from the resulting dive, the engine began to run rough and would only produce partial power.
Pilot Actions
The pilot checked the mixture control, magnetos, fuel quantity, fuel valve, and carburetor heat. Despite these efforts, the engine would only produce 1,400 RPM, and the pilot was unable to maintain altitude. He executed a forced landing to a rough plowed field. During the landing roll, the aircraft nosed over.
Post-Incident Examination
An airframe and powerplant (A&P) mechanic examined the aircraft engine and found no discrepancies in the engine controls or aircraft fuel system.
Conclusion
The partial loss of power and subsequent forced landing resulted from an engine issue that was not identified during post-incident inspection.