On June 4, 2004, approximately 1800 central daylight time, an Air Tractor AT-301 single-engine agricultural airplane, N3166U, was substantially damaged during a forced landing following a loss of engine power while maneuvering near Cotton Plant, Arkansas. The commercial pilot was not injured. The airplane was registered to Neal Aircraft Inc., of Slaton, Texas, and operated by Southern Air, Inc., of Cotton Plant, Arkansas. Visual meteorological conditions prevailed for the 14 Code of Federal Regulations Part 137 aerial application flight. The local flight originated from a private airstrip near Cotton Plant, Arkansas, at an unknown time. The 300-hour pilot reported in the Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2) that he was performing an aerial application of fertilizer on a field for about 4 hours. On the second to last pass, the "engine started to sputter" and he initiated a forced landing to an adjacent field. During the landing roll, the airplane nosed over and came to rest inverted. Examination of the airplane by an Federal Aviation Administration (FAA) inspector, who responded to the accident site, reported that the vertical stabilizer, rudder and elevators were structurally damaged. The engine mounts were also damaged. Both fuel tanks remained intact. No fuel residue was observed on the soft ground. The inspector added that about a cup of fuel was found in each of the fuel cells. Recovery personnel were asked to evaluate any remaining fuel after the aircraft was up-right, and all estimates were that there was less than one gallon of fuel remaining in the aircraft.