On May 30, 2000, at 1730 central daylight time, an Air Tractor AT-301 agricultural airplane, N8594S, sustained substantial damage during a forced landing following a loss of engine power near Garwood, Texas. The airplane, owned by a private individual doing business as ANF Air Service, Inc., was operated under 14 Code of Federal Regulations Part 137. The commercial pilot, sole occupant, received minor injuries. Visual meteorological conditions prevailed for the local aerial application flight, and a flight plan was not filed. The flight originated from a private turf airstrip, approximately 30 minutes prior to the accident. The pilot and operator reported that the pilot had flown the airplane approximately 8 flight hours that day with numerous takeoffs and landings from the dirt airstrip near the rice field which the pilot was spraying with fertilizer. During the swath, the "engine lost power and started blowing smoke." The pilot dumped the hopper load and initiated a forced landing to the airstrip; however, the airplane impacted the terrain approximately 200 feet short of the runway. During the forced landing, the airplane cleared a levee, struck the ground, spun around and came to rest upright. The operator and the FAA inspector found the engine separated from the airframe. Structural damage occurred to the horizontal stabilizer. Oil covered the windshield and portions of the airframe. The operator stated that the supercharger seal failed.