AIR TRACTOR INC AT-602

Full Narrative

HISTORY OF FLIGHTOn June 14, 2024, about 0700 central daylight time, an Air Tractor AT-602 airplane, N115AA, was destroyed when it was involved in an accident near Broseley, Missouri. The pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 137 agricultural application flight.
The operator reported that the pilot departed a private airstrip about 0600. At takeoff, the fuel load was about three-quarters capacity and the hopper was fully loaded. The pilot was planning to apply the fertilizer to a field about 1/2-mile north-northwest of the accident site.
An individual located 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 sheriff’s office reported that an individual contacted their office about 0830 to report the airplane was overdue. A search located the accident site a short time afterward.
The accident site was located about 3 miles northeast of the departure airstrip and about 1/2-mile southeast of the field being sprayed. The airplane impacted a wooded area adjacent to a soybean field and a postimpact fire ensued. The soybeans were 2 to 3 ft high, and the trees were 20 to 30 ft tall. There were no power lines, towers, or guy wires observed in the immediate vicinity of the accident site.
The owner of the application 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 employees of the farmer found that the pilot had potentially made one application pass on the field. No evidence of multiple application passes was observed.
No airplane position data for the accident flight was available. The airplane was equipped with a satellite tracking system; however, that system was destroyed by the postimpact fire. No ADS-B data for the airplane was located. PERSONNEL INFORMATIONThe pilot’s flight time logbook was not available to the investigation. WRECKAGE AND IMPACT INFORMATIONThe airplane came to rest upright about 35 ft from the south edge of the woods oriented on a southwest heading. The propeller assembly with the engine power section module attached was located adjacent to the impact crater. The power section had separated from the remainder of the engine assembly. A portion of the left wing tip, including the navigation/strobe light assembly, was located about 160 ft east of the main wreckage at the edge of the wooded area.
Multiple tree propeller cuts and tree breaks were present in the immediate vicinity of the wreckage. One tree, about 14 inches in diameter near the base, was broken off about 12 ft above ground level. It also exhibited five propeller cuts beginning about seven feet above ground level and progressively increasing in depth moving lower on the tree.
Detailed airframe, engine, and propeller examinations did not reveal any anomalies associated with a preimpact failure or malfunction. The airframe exhibited damage consistent with the impact to trees and terrain. No indication of an inflight structural failure was observed. The flight control surfaces were present at the accident site. Flight control system components displayed multiple separations; however, metallurgical examination revealed signatures consistent with overload separations.
The engine exhibited internal contact signatures consistent with rotation at impact. The propeller blades displayed chordwise abrasions, forward bending, and leading edge damage. The propeller cylinder exhibited damage consistent with the piston and blades being in the normal operating range at impact. MEDICAL AND PATHOLOGICAL INFORMATIONAn autopsy of the pilot was conducted by the Butler County Coroner. According to the autopsy report, the cause of death was multiple blunt force injuries, and the manner of death was accident. Toxicology testing performed at the FAA Forensic Sciences Laboratory revealed a low level of glucose (27 mg/dL) in urine, and the presence of naproxen in liver and muscle tissue. Naproxen is a non-prescription NSAID used to treat pain and inflammation and is normally acceptable for pilots. Ethanol was not detected.