On June 16, 2015, about 1030 Pacific daylight time, a Rockwell International S-2R, airplane, N8420V, sustained substantial damage during landing roll and subsequent noseover, in an adjacent field to the Kinch Farms Airport, Washtucna, Washington. The commercial pilot, sole occupant of the airplane, was seriously injured. The airplane was registered to B & R Aerial Crop Care, Inc., and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 137 as an agricultural application flight. Visual meteorological conditions prevailed and no flight plan was filed for the local flight. In a written statement, the pilot stated that during the 10th landing of the day on runway 3, the wind shifted resulting in a quartering tailwind. During the landing, he lost directional control and the airplane veered left into an adjacent field. The field had recently been plowed, and the soil was soft. Subsequently, the airplane nosed-over, resulting in substantial damage to the canopy roll cage structure. The pilot reported no mechanical malfunctions or failures with the airplane that would have precluded normal operation. The nearest weather reporting station reported wind near the time of the accident was from 130 degrees at 5 knots, gusting up to 10 knots. A postaccident examination of the airplane was conducted by the Federal Aviation Administration (FAA). The cockpit overhead structural tubing was bent, and the pilot's helmet had impact marks.