On April 3, 1998, at 1000 central standard time, a Piper PA-25-235, N7108Z, was substantially damaged following a total loss of engine power and subsequent forced landing in a farmer's field. The commercial pilot reported no injuries. The 14 CFR Part 91 maintenance flight was not operating on a flight plan. Visual meteorological conditions prevailed at the time of the accident. The flight departed Sabetha Municipal Airport, Sabetha, Kansas, at 0955. According to the pilot's written statement, the purpose of the flight was to calibrate the sprayers on the aircraft. The pilot stated that the aircraft lost engine power while maneuvering near the airport and he was unable to restart the engine. The pilot stated that he landed the airplane in a pasture and the airplane came to rest after a short slide. The accident engine was inspected by the Federal Aviation Administration (FAA) Flight Standards District Office (FSDO), Wichita, Kansas, and no anomalies were found.