On July 19, 1994, at 0730 mountain daylight time, a Piper PA-25- 235, N6580Z, registered to Arlie L. Aeschliman of Syracuse, Kansas, and piloted by a commercially certificated pilot, was destroyed during a collision with high standing corn and terrain. 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 no injuries. The flight departed from Tribune, Kansas, exact time unknown. The pilot reported, on his NTSB Form 6120.1/2, that he passed over powerlines and settled above the corn crop to begin his first spray run over the field. He stated that as he was opening the spray valve, the airplane "suddenly settled without responding to any control movement." A Federal Aviation Administration Principal Operations Inspector (POI) interviewed the pilot. He said the pilot felt he had hit some bad air or possibly a dust devil as he flew over the powerlines. The pilot, according to the POI's statement, said the airplane's engine and systems were operating normal just before and during the events leading to the accident. The pilot said he did not decelerate the airplane using rapid or more than normal elevator back pressure force. The pilot said the surface temperature just before takeoff was about 70 degrees Fahrenheit. He said the temperature at 400 feet above ground was about 85 degrees Fahrenheit with very light turbulence.