On July 14, 2001, at 1340 central daylight time, a Piper PA-36-300, N9900P, sustained substantial damage when the airplane impacted a muddy field near Langdon, North Dakota. The agricultural flight was operating under the provisions of the 14 CFR Part 137 and was not on a flight plan. The commercial pilot was not injured. The aerial application flight departed at 1330 from a private airstrip near Langdon, North Dakota. The pilot reported that on his first run he had 200 gallons of chemicals and 60 gallons of fuel. The pilot reported, "I took off from the airport and went around town. When I was com[m]ing up to a set of power lines I hit an air pocket and didn't have enough altitude to clear the lines so I turned to the east and hit the ground." The pilot reported the airplane did not have a mechanical malfunction.