On August 19, 1994, at 0720 central daylight time (cdt), a Cessna 188, N133MC, registered to Max Birney Aerial Spraying Service, Incorporated of Sublette, Kansas, and piloted by a private pilot, was substantially damaged during a collision with an irrigation sprinkler and the ground shortly after takeoff. Visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 137 flight was not operating on a flight plan. The pilot reported minor injuries. The flight departed a farm field 16 miles northwest of Sublette, Kansas, at 0720 cdt. According to the pilot's statement on NTSB Form 6120.1/2, the airplane was loaded with "...900 pounds of wheat seed...." The pilot said the airplane "took the entire length of the pasture runway to get airborne." He said the airplane was "... too heavy and would not gain altitude." The load was not jettisoned in time and the airplane collided with an irrigation sprinkler and ground according to the pilot.