History of Flight
On October 8, 2017, about 1257 central daylight time, an Aero Vodochody L39C, registration N580LL, collided with terrain half a mile south of Wilbarger County Airport (F05), Vernon, Texas. The commercial pilot was fatally injured and the airplane was destroyed. The airplane was owned and operated by the pilot under 14 CFR Part 91. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight, which had departed from F05 about 1153.
Eight witnesses provided accounts that varied in details. All agreed that the airplane made a pass over runway 20, with estimated altitudes ranging from 50 to 300 ft above ground level. One witness thought the airplane might be conducting a go-around. The airplane then made a sharp left bank; witnesses estimated the bank angle between 45° and 90°. Two witnesses believed the pilot was attempting a barrel roll. One witness stated that the airplane entered an inverted attitude and spun to the ground; others reported that the left wing struck the ground before impact.
Another witness, driving north along the highway adjacent to the airport, saw the airplane fly by at low altitude. He noted the nose came up slightly and it entered a steep left bank, such that the entire profile was visible. He then observed a fireball and black smoke.
A GoPro camera recovered from the wreckage was sent to the NTSB Vehicle Recorders Division. The internal microSD card was catastrophically damaged and data unrecoverable.
Personnel Information
The pilot held a commercial pilot certificate with ratings for airplane single- and multi-engine land and instrument airplane, along with a type rating in the Aero Vodochody L39. His second-class FAA medical certificate, dated August 25, 2017, required corrective lenses. On the application, the pilot reported 1,124 total flight hours, with 17 hours in the previous six months.
Aircraft Information
The airplane was manufactured in Czechoslovakia in 1984 as a training aircraft for Warsaw Pact countries. It was equipped with an Ivchenko AI-25-TL turbofan engine rated at 3,792 lbs of thrust. The most recent condition inspection of the airframe and engine was completed on August 8, 2017, at total times of 1,440.5 and 894.7 hours, respectively. The engine had 107.7 hours since last overhaul. The transponder, altimeter, and encoder were also checked and recertified.
Meteorological Information
The 1255 automated observation at F05 recorded wind from 210° at 14 knots, visibility 10 miles, clear skies, temperature 28°C, dew point 6°C, and altimeter setting 29.70 inches of mercury.
Wreckage and Impact Information
On-site investigation revealed a 40-ft long ground scar consistent with the left wing contacting the ground, leading to a 50-ft long crater. The airplane fragmented, leaving a 580-ft long debris path aligned on a 170° magnetic heading. Surrounding grass burned from a flash fire likely ignited by vaporized fuel. The airplane itself was fragmented and burned. The right wing separated with the aileron missing; the left wing was destroyed. The empennage was identified. The engine compressor showed signatures consistent with rotation followed by sudden stoppage, with broken or crushed guide vanes and scoring on the engine case. Flight control continuity could not be established due to impact damage, but pushrod movement was noted when the elevators and rudder were moved by hand.
Medical and Pathological Information
An autopsy performed by the Office of the Chief Medical Examiner, Tarrant County, Texas, attributed the pilot's death to multiple traumatic injuries due to an airplane crash. Toxicology testing was negative for ethanol and drugs; carbon monoxide tests could not be performed. Although thermal injuries were present, the trachea showed no soot deposition.
The FAA Bioaeronautical Sciences Research Laboratory detected 24 mg/dL ethanol in muscle tissue, but putrefaction was noted, indicating the ethanol likely originated from sources other than ingestion. Additionally, ondansetron (Zofran) was detected in liver and muscle tissue; ondansetron is a non-sedating antiemetic used to treat nausea and vomiting.