On September 27, 2000, at 1430 Pacific daylight time, an Air Tractor AT-602, N5111A, registered to and operated by Weaver Flying Service as a 14 CFR Part 137 aerial application flight, collided with power lines and subsequently the terrain near Columbia River, Washington. Visual meteorological conditions prevailed at the time and no flight plan was filed. The aircraft was substantially damaged and the commercial pilot, the sole occupant, was not injured. The flight originated from a private airstrip in Quincy, Washington, about 15 minutes prior to the accident. In a written statement, the pilot reported that he over flew the area to be sprayed to check for people, obstacles and the wind condition. The pilot stated that he noted the powerlines on the northeast side of the field and trees running east/west on the north end. The pilot made the first spray pass to the north, on the east side of the field, paralleling smaller power lines. When the pilot pulled up on the north end of the field, the aircraft collided with the powerlines in the northeast corner of the field. The engine began to lose oil and power. The pilot then maneuvered the aircraft for a forced landing in an apple orchard. The aircraft collided with several small apple trees before coming to rest.