CEN24FA220 · Air Tractor Inc AT-602

The operator reported that the pilot departed to apply fertilizer to a field about 4 miles north of the airstrip. An individual about 2 miles from the accident site reported hearing what he believed was the accident airplane for a total of about 15 minutes. The pilot seemed to be flying in the vicinity of the accident site, and for most of that time the sound of the engine seemed normal. However, toward the end of that time the pitch of the engine increased slightly for about 3 or 4 seconds before the sound then completely faded away. He did not hear the airplane again nor did he hear the impact. The flight was reported overdue about 90 minutes after takeoff when the pilot had not returned. A search subsequently located the accident site about 3 miles from the departure airstrip: the airplane impacted a wooded area adjacent to a soybean field and a postimpact fire ensued. There were no power lines, towers, or guy wires observed in the immediate vicinity of the accident site. The owner of the field reported that the pilot was scheduled to apply fertilizer to three of his fields that day. A visual examination of the field that morning by the farmer’s employees found that the pilot likely made one application pass on the field. No evidence of multiple application passes was observed. Multiple tree propeller cuts and tree breaks were present in the immediate vicinity of the wreckage. Detailed airframe, engine, and propeller examinations did not reveal any anomalies associated with a preimpact failure or malfunction, including an inflight structural failure or flight control system anomaly. The examinations determined that the engine was operating and the propeller blades were rotating under power at the time of impact. Day visual meteorological conditions prevailed at the time of the accident. There was nothing in the results of the autopsy or toxicology to suggest pilot impairment or incapacitation. Because no airplane position data for the accident flight was available, an airplane performance analysis could not be conducted. The confined area of the wreckage and the limited tree damage outside of the immediate vicinity of the accident site suggested a high angle of descent such as found following an inadvertent aerodynamic stall. However, without any additional data, the reason for the pilot’s inflight loss of control could not be determined.

Verbatim NTSB analysis and probable cause from the NTSB dataset