History of Flight
On June 6, 2016, at about 0745 Pacific daylight time, a Rockwell International S-2R restricted-category agricultural airplane, registration N4191X, was substantially damaged during a collision with guy wires, powerlines, and trees. The accident occurred about 3 nautical miles west of De Smet, Idaho, while the airplane was engaged in an aerial application flight. The airplane was owned and operated by Faunce Ag Aviation Inc., Tekoa, Washington. The commercial pilot, the sole occupant, sustained fatal injuries. Visual meteorological conditions prevailed, and the flight was conducted under 14 Code of Federal Regulations Part 137 without a flight plan. The flight had departed a private airstrip near Tekoa at about 0700.
A witness watching from her residence about 700 ft east of the accident site observed the pilot spraying a field north of the road. The pilot was making spray passes in west and east directions parallel to a powerline along the south side of the field. She saw the airplane flying south along the west side, then turn left to an easterly heading and begin a spray pass on the south edge next to the powerline. Shortly afterward, she saw downed powerline wires and heard the sound of impact, though she did not witness the collision with the wires.
The property owner, interviewed by the National Transportation Safety Board (NTSB) investigator-in-charge, stated the pilot was applying a fungicide to a wheat field. The owner noted the pilot had sprayed the field for the past 25 years and was very familiar with the environment, having no previous issues.
According to a family member familiar with the operation, interviewed by a Federal Aviation Administration (FAA) safety inspector, the accident occurred on the pilot's fourth load of the morning. The amount of chemical loaded was not determined.
Personnel Information
The pilot held a commercial pilot certificate with an airplane single-engine land rating and a second-class medical certificate issued January 12, 2016, with limitations: "Not valid for night flying or by color signal control. Not valid for any class after January 31, 2017." According to operator records, the pilot had accumulated 10,109 total flight hours, with 7,124 hours in the accident airplane make and model. The pilot's personal logbook was not provided.
Aircraft Information
The single-seat, low-wing, fixed-gear, tailwheel-equipped airplane, serial number 1956R, was manufactured in 1974. It was powered by a Garrett TPE331-6-252M engine, serial number P-03069C, rated at 715 horsepower. The last annual inspection was on November 6, 2015, at a total airframe time of 9,944 hours and engine time of 9,888.7 hours. The airplane had accumulated 167.1 hours since that inspection.
Meteorological Information
At 0753, the Pullman/Moscow Regional Airport (PUW) reported wind calm, visibility 10 miles, sky clear, temperature 23°C, dew point 13°C, altimeter 29.92 inHg. At the accident time, the sun was about 13.8° above the horizon, and its lateral position was about 20° left of the airplane's eastbound spray run heading.
Wreckage and Impact Information
An NTSB investigator and FAA inspector surveyed the accident site the following day. Physical evidence showed the airplane first impacted a set of guy wires about 660 ft west of where it entered the field on the spray run. The guy wires were secured to the top of a utility pole supporting the powerline along the south field edge, descending at about a 45° angle and anchored about 65 ft north of the pole. After hitting the guy wires, the airplane collided with and went through powerline wires, crossed a county road, and struck a stand of fir trees. It came to rest in the trees about 490 ft southeast of the initial impact. An outboard right wing section, about 30 inches long, was found about 160 ft east-southeast of the first impact. Yellow and black paint chips consistent with the wing's paint scheme were located about 100 ft southeast of the guy wires.
The airplane was severely fragmented and deformed. Except for about 7 ft of the inboard forward spar, the right wing separated from the fuselage and was destroyed. The left wing and aft fuselage from cockpit to forward empennage were completely separated and destroyed. The entire empennage separated and was located about 20 ft south of the main wreckage. The engine remained attached at its mounts. The cockpit was crushed and deformed. With the exception of the outboard right wing section, the wreckage was within a 50-ft radius. No catastrophic mechanical anomalies were found with the engine or airframe that would have precluded normal operation.
Medical and Pathological Information
An autopsy attributed the cause of death to blunt force trauma. Toxicological testing by the FAA's Bioaeronautical Research Laboratory was negative for carbon monoxide and ethanol; ibuprofen was detected in cavity blood. Testing for cyanide was not performed. Ibuprofen is a nonsteroid anti-inflammatory drug commonly used for pain, fever, and inflammation.