NTSB Factual Report

On July 7, 2016, at 0650 central daylight time, an Air Tractor Inc AT-602, N967JB, collided with power lines and terrain during an aerial application of a field about 4 miles northeast of Kennett, Missouri. The airplane was destroyed by impact forces. The commercial pilot sustained fatal injuries. The airplane was registered to and operated by Bootheel Air Services LLC under 14 Code of Federal Regulations Part 137 as an aerial application flight that was not operating on a flight plan. Visual meteorological conditions prevailed at the time of the accident. The local flight last departed from Hornersville Memorial Airport (37M), Hornersville, Missouri, about 0541.

According to a Federal Aviation Administration (FAA) inspector, a chemical loader stated that the airplane was loaded at 37M with 375 gallons of liquid chemical applicant to spray a 75-acre corn crop field, which was adjacent to a bean field. There were no witnesses to the accident.

The accident site was located near electrical lines that were oriented in an east/west direction and in the middle of the corn field that was being sprayed by the airplane. Two of the electrical lines were severed and a third damaged near the east edge of the field. A section of the airplane spray boom was bent around and hanging from the damaged, third electrical line. There was a ground scar consistent with the airplane's impact with terrain approximately 1,000 feet from the severed/damaged electrical line and in the bean field adjacent to the corn field. Approximately 50 feet from the severed/damaged lines, there were sections of right wing and aileron on the ground. The ground scar extended in the bean field and inn a northerly direction for approximately 200 feet. There were several propeller strikes in the ground near the beginning of the wreckage path.

The propeller blades, propeller hub, engine, and landing gear were found separated from the airplane. The fuselage, remaining wing, and empennage were located near the end of the wreckage path. The cockpit and tail section had an approximate tail-to-nose heading oriented towards the south.

Examination of the flight control confirmed flight control continuity. The engine turbine blades display signatures consistent with engine power. Fuel quantity could not be verified, but a fuel spill was noted underneath the wing section. There was no evidence of remaining spray chemical solution on scene. The shoulder harness air bag restraint system was deployed.

The 48-year-old pilot had reported multiple orthopedic surgeries and use of medication for high cholesterol to the FAA. At the time of his last aviation medical examination, diabetes was diagnosed and treatment with metformin initiated. The aviation medical examiner questioned records from a recent hospitalization that stated the pilot had anxiety/depression but was told this was not a current diagnosis and that he had not been on medication in years. According to the autopsy performed by Mineral Area Pathology LLC, the cause of death was multiple blunt force injuries and the manner of death was accident. No significant natural disease was identified. Toxicology testing identified acetaminophen, chlorpheniramine, citalopram and its metabolite n-desmethylcitalopram, dextromethorphan and its metabolite dextrorphan in liver. Acetaminophen and chlorpheniramine were found in cavity blood and the rest were found in muscle. Acetaminophen was identified in urine.

Acetaminophen is an analgesic and fever reducer available over the counter in many products; it is commonly marketed as Tylenol. Chlorpheniramine is a sedating antihistamine available over the counter in many cold, cough, and allergy preparations. It carries this warning, "May impair mental and/or physical ability required for the performance of potentially hazardous tasks (e.g., driving, operating heavy machinery)."

Citalopram is a prescription antidepressant medication often marketed with the name Celexa. It carries this warning, "In studies in normal volunteers, citalopram in doses of 40 mg/day did not produce impairment of intellectual function or psychomotor performance. Because any psychoactive drug may impair judgment, thinking, or motor skills, however, patients should be cautioned about operating hazardous machinery, including automobiles, until they are reasonably certain that citalopram therapy does not affect their ability to engage in such activities." N-desmethylcitalopram is its primary metabolite.

Major depression itself is associated with significant cognitive degradation, particularly in executive functioning. The cognitive impairment often resolves as the emotional symptoms resolve. The FAA requires that pilots treated for depression undergo specific testing to ensure their cognitive functioning is intact and they are using a non-impairing antidepressant. The FAA's Guide for Aviation Medical Examiners states "The use of a psychotropic drug is disqualifying for aeromedical certification purposes – this includes all antidepressant drugs, including selective serotonin reuptake inhibitors (SSRIs). However, the FAA has determined that airmen requesting first, second, or third class medical certificates while being treated with one of four specific SSRIs may be considered. The Authorization decision is made on a case by case basis. The Examiner may not issue." The four potentially allowable antidepressants are fluoxetine (Prozac), escitalopram (Lexapro), sertraline (Zoloft), and citalopram (Celexa).

Dextromethorphan is a cough suppressant available over the counter in many products. At usual dosing, it is not considered impairing. Dextrorphan is its primary metabolite.

NTSB Probable Cause

The pilot's failure to maintain clearance from power lines while maneuvering during the aerial application flight.