History of Flight
On July 29, 2016, at 0914 central daylight time, an Air Tractor AT-402 airplane, registration N1016G, collided with power lines and impacted terrain near Sac City, Iowa. The commercial-rated pilot was fatally injured, and the airplane was destroyed. The airplane was operated by a private individual under 14 Code of Federal Regulations Part 137 as an aerial application flight. Visual meteorological conditions prevailed, and no flight plan was filed. The airplane departed Arthur N Neu Airport (CIN) in Carroll, Iowa, at 0902 and was spraying in the area of Sac City Municipal Airport (SKI), Sac City, Iowa.
The pilot's ground crewman stated that he met the pilot at CIN around 0830 and loaded the airplane with 375 gallons of liquid applicant and 130 gallons of fuel, noting that the airplane was almost fully loaded and within specified limitations. He added that the pilot did not seem concerned about running late, seemed complacent, and did not appear rushed or nervous, which was unusual. The ground crewman described the area near the accident site as a "wire farm" due to the number of power lines present.
Personnel Information
A review of the pilot's logbooks and flight data revealed that he had accumulated 1,746.2 total flight hours and 414.1 hours in the Air Tractor AT-402. In the preceding 30 days, he had flown 114.5 hours, all in the accident airplane.
Wreckage and Impact Information
The main wreckage was located in a corn field about one mile south of SKI. The field being treated was north of the accident site. A large set of power transmission lines ran east to west along the southern border of the target field. The power lines and supporting tower structures were 80 to 90 ft tall, with the lines sagging between towers. A farm house and several farm buildings were located south of the power lines.
The wreckage debris path was oriented north to south and featured a swath cut through mature corn, continuing to the main wreckage about 900 ft south of the power lines and 75 ft south of the initial impact area. A smell consistent with jet fuel and agricultural chemical was present, and the ground was damp. No evidence of fire was found. The debris path began with the entire rudder on a gravel road under the power lines, followed by a portion of the vertical stabilizer on the north side of the farm house, then the swath of cut corn and initial ground impact point.
The forward cockpit wall was part of the hopper structure and lay adjacent to the fuselage. The instrument panel remained mostly intact and undamaged; the Hobbs meter showed 7,008.3 hours. The center fuselage between the firewall and cockpit was crushed, and the fuselage was bent and twisted left, coming to rest next to the left wing. The horizontal stabilizers and elevators exhibited minimal damage and remained attached. The lower portion of the vertical stabilizer remained attached to the empennage and showed a jagged horizontal cut at the top.
The right and left wings remained connected at the center splice joint. No prominent impact marks were on the leading edge or upper surface of the wings, but the bottoms exhibited impact damage. The outboard section of the right flap was bent under the inboard half. Both wing fuel tanks were breached at the inboard ends, with fuel caps secure. Control continuity was established despite impact damage. The elevator controls were continuous from the control stick to the elevators. Rudder cables were continuous to the aft fuselage, where they separated with signs of tension overload. The control stick remained attached to the torque tube. The flap actuator was in the retracted position. The trim system was continuous.
The main landing gear separated from the fuselage. The four-point pilot restraint system remained fastened, with the lap belt cut by first responders; shoulder harness straps had separated from the lap belt attachments with slight fraying. The engine sustained impact damage and remained attached to its mounts; the exhaust housing was damaged. The engine separated at the "C" flange, revealing the interstage baffle and power turbine wheel with damage to all blades and rotational scoring. The propeller hub and spinner remained attached; one blade remained, and two others were not found at the scene.
The airplane was equipped with a single curved acrylic windscreen, an aluminum bar in front, and a deflector cable from the canopy to the vertical stabilizer for wire strike protection. The aluminum bar was found separated from its lower base, bent left into a V-shape with an inside angle of about 45°. A 6 ft piece of deflector cable remained attached to the top of the bar, showing abrasion and damage. The upper right corner of the cockpit structure showed cylindrical abrasions and damage. The top 15 inches of the vertical stabilizer were separated with a jagged horizontal cut and impact damage; a portion of the deflector cable remained attached. The rudder had a 4-inch gouge into the vertical hinge line.
Additional Information
A Satloc M3 Bantam GPS and a Garmin aera 510 GPS were recovered from the wreckage and downloaded by the NTSB Recorders Laboratory. The combined data plotted on Google Earth showed a red flight path originating from the southeast and proceeding directly to the target field without an initial circling pass. Green areas indicated when the spray function was active. White lines represented the power lines crossing the flight path west to east.
A landowner near the accident site observed a few round, orange objects similar to high visibility power line markers on the road. The power company reported that no markers were installed on the power lines prior to the accident and could not find documentation of such markers. After the accident, the power company installed several high visibility markers on the new power lines.
Medical and Pathological Information
The Iowa Office of the State Medical Examiner completed an autopsy on the pilot, listing cause of death as multiple blunt force injuries. The FAA's Bioaeronautical Sciences Research Laboratory conducted toxicology testing, which was negative for ethanol and drugs.