What happened
The pilot was operating the aircraft during cruise flight when the engine began to exhibit irregular operation. Upon reducing power to idle, the misfiring ceased temporarily. However, when the throttle was advanced back to cruise power settings, the engine misfired several more times before the number one cylinder physically separated from the engine.
Following the mechanical failure, the pilot executed a forced landing into an agricultural field containing corn that was approximately six to eight feet high. During the landing roll, the aircraft nosed over and ultimately came to rest in an inverted position.
The investigation
Examination of the engine revealed evidence indicating that the number one cylinder was loose prior to its separation from the engine block.