Incident Overview
On the first flight following maintenance, the pilot experienced a sudden loss of engine power during the initial climb. The pilot reported that the engine stopped producing power and began behaving erratically. In response, the pilot declared an emergency to air traffic control and initiated a return to Palwaukee Municipal Airport.
Pilot Report
According to the pilot, the engine was "backfiring and sounded like only one cylinder was hitting." Unable to maintain altitude, the pilot selected a nearby field for a forced landing. After circling the field twice, the pilot executed a landing on an easterly heading. Upon touchdown, the aircraft skidded and rolled for approximately 250 yards before coming to rest on the bank of a small creek. The pilot evacuated the airplane and waited for assistance.
Post-Incident Examination
An examination of the number four cylinder revealed excessive black carbon buildup on the cylinder head and exhaust valve seat. No other mechanical anomalies were reported in the source.
Probable Cause
The source does not state a probable cause for the incident.