History of Flight
On March 20, 2016, about 1110 mountain daylight time, an Aeronca 7AC airplane, N84580, impacted terrain near Ellsworth, Nebraska. The private pilot sustained fatal injuries, and the airplane was destroyed. The airplane was registered to and operated by the pilot under 14 CFR Part 91 as a personal flight. Day visual meteorological conditions prevailed for the local flight, which departed without a flight plan from Alliance Municipal Airport (AIA), Alliance, Nebraska. At 1000, an airport surveillance camera captured the airplane departing from AIA. About 1100, the pilot's brother observed the airplane maneuvering near his home, about 31 miles northeast of AIA. After concerned family members reported the pilot missing, the accident site was located on March 22, 2016, about 4 miles southwest of the brother's home.
Personnel Information
The pilot, age 68, held a private pilot certificate with an airplane single-engine land rating. He was last issued an FAA third-class medical certificate on July 7, 2005, and held a valid driver's license. The Aeronca 7AC is defined by the FAA as a light sport aircraft (LSA). Pilots flying LSAs are only required to possess a valid driver's license and comply with 14 CFR 61.53(b). A review of the pilot's logbook showed 355 total flight hours, with 3 hours in the last 30 days. The most recent flight review was completed on February 22, 2016.
Aircraft Information
The airplane, serial number 7AC-3289, was manufactured in 1946 and registered to the pilot on September 10, 2013. It was a two-place, tandem, high-wing monoplane equipped with a Lycoming O-235-C1 engine, rated at 115 horsepower at 2,600 rpm. The most recent annual inspection was completed on July 25, 2015, at a total time of 1,848.2 hours. The airplane had accumulated 7 hours since that inspection. Although it held a standard airworthiness certificate, it met the definition of an LSA. The mechanic who performed the last annual inspection stated that an engine exhaust muffler crack was discovered in September 2015, located near a weld the pilot had performed. A new muffler was in the pilot's hangar at the time of the accident.
Meteorological Information
At 1053, the weather observation station at AIA, about 27 miles southwest of the accident site, reported wind variable at 6 knots, 10 miles visibility, clear skies, temperature 6°C, dew point minus 12°C, and an altimeter setting of 30.23 inches of mercury.
Wreckage and Impact Information
The aircraft impacted rolling terrain on a southeasterly heading. The main wreckage came to rest upright on a northerly heading, about 340 ft from the initial impact point. The left and right wings separated from the fuselage, with wood spars fractured near the wing roots. The right wing was about 210 ft northwest of the main wreckage, and the left wing was about 5 ft to the right of the main wreckage. The propeller separated and came to rest about 180 ft northwest of the main wreckage. Flight control surfaces remained attached; cables had normal continuity except the aileron cable, which was fractured in four locations with broomstraw appearance consistent with overload. No preimpact anomalies were noted with the flight control system. The engine remained attached; spark plugs showed normal wear, and a borescope inspection revealed no anomalies. Both magnetos produced spark. The carburetor float bowl had no anomalies. Propeller blades were twisted and curled aft with chord-wise polishing, consistent with operation at impact. The cabin heat control was off. The left muffler shroud was removed; the muffler was rusted and cracked in several locations, and the shroud contained exhaust residue. A carbon monoxide detector was not located in the wreckage.
Medical and Pathological Information
The pilot had reported no chronic medical conditions or medications during his last FAA medical exam in 2005. However, personal medical records showed treatment for prostate cancer in 2000 and intermittent treatment for hypertension. He underwent angioplasty and stenting for severe coronary artery disease in 2009 and 2011. Since 2013, he was treated for stress, insomnia, and anxiety with temazepam and buspirone. In 2011, he was diagnosed with obstructive sleep apnea and instructed to use a CPAP machine. A 2016 review indicated he was not using it to the desired extent. As of February 18, 2016, his medications included aspirin, finasteride, tamsulosin, simvastatin, metoprolol, clopidogrel, buspirone, temazepam, and nitroglycerin as needed. An autopsy determined the cause of death as blunt force trauma, manner accident, and also identified coronary artery disease with 50% stenosis. Toxicology testing identified carbon monoxide (carboxyhemoglobin) at 40% in subclavian blood, along with metoprolol, buspirone, and temazepam. Diazepam, oxazepam, and ranitidine were identified in urine. The pilot was not a smoker. Carboxyhemoglobin levels between 10% and 20% can result in confusion, impaired judgment, and difficulty concentrating.