On September 15, 1993, at 1130 hours Pacific daylight time, a Cessna A188B, N9523G, collided with power lines during an aerial application flight near Waterville, Washington. Visual meteorological conditions prevailed at the time and no flight plan was filed for the local flight. The airplane was destroyed by a post impact fire and the certificated commercial pilot was fatally injured. The flight had originated from Waterville and was spraying a herbicide. Witnesses in the area reported that they had observed the airplane flying in the area for most of the day. The airplane was spraying a field and making passes under the high tension lines before pulling up to make another pass. During the last pass, the witnesses observed something come off the airplane as it passed under the lines. The airplane climbed steeply, then turned to the left descending rapidly and impacted the ground. A post crash fire ignited and consumed the airplane. Post crash inspection of the area revealed damage was noted to two of the 1.3 inch diameter wires. The wires were approximately 100 feet above ground level. The terrain was slightly rolling with short dry grass covering the ground. The airplane's canopy had separated as well as the top of the vertical stabilizer. Both areas indicated evidence of impact with the wires.