On April 21, 2004, approximately 1230 central daylight time, an Air Tractor 502B single-engine airplane, was destroyed by fire after it collided with terrain during takeoff from Powell Ranch near San Angelo, Texas. The commercial rated pilot, sole occupant of the airplane, was not injured. Visual meteorological conditions prevailed and no flight plan was filed for the local, aerial application flight conducted under 14 Code of Federal Regulations Part 137. According to the pilot, he stated that he "didn't plan well" for the flight. He attempted to takeoff on about a 180-degree heading from a 3,000-foot-long dirt strip on a hot day with 500 gallons of chemicals on board, full fuel tanks, and a crosswind. He applied full power, started the take-off roll, and the airplane became airborne. But, when the airplane got to the end of the runway, it "wouldn't fly." The pilot tried to dump the chemical load, but was unsuccessful. Subsequently, the landing gear contacted tree tops, and the airplane rolled and collided with the ground. Once the airplane came to a stop, it caught on fire. The pilot reported a total of 14,522 flight hours, of which, 577 hours were in this make and model airplane. He also reported there were no mechanical deficiencies. The weather observation facility at San Angelo Regional Airport/Mathis Field (SJT), near San Angelo, Texas, approximately 20 miles northwest of Powell Ranch, at 1251, reported the wind from 250 degrees at 12 knots gusting to 16 knots, 10 statute miles visibility, sky clear, and a barometric pressure setting at 29.71 inches of Mercury. The temperature was 84 degrees Fahrenheit, and the dew point was 37 degrees Fahrenheit. The field elevation was 1,919 feet mean sea level. The density altitude was calculated by the investigator-in-charge at 4,179 feet.