History of Flight
On September 12, 2015, about 1625 eastern daylight time, an Aero Vodochody L-39C Albatros, N139RT, was destroyed when it impacted terrain shortly after takeoff from Scott Municipal Airport (SCX), Oneida, Tennessee. The airline transport pilot was fatally injured. The airplane was registered to Float Dancer, Inc., and operated by the pilot under 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed, and no flight plan was filed for the local airshow performance flight.
According to witnesses, the pilot flew the airplane to SCX the day before the accident to perform in the Wings Over Big South Fork airshow. Witnesses reported that the pilot was scheduled to be the final performer. A friend of the pilot, who had flown the airplane about a week before and assisted on the day, reported that he removed the safety pins for the front cockpit ejection seat, filled the smoke system oil tank, and observed the pilot perform a full power engine check and smoke system check before takeoff from runway 23. He stated the takeoff "appeared normal in all respects." As the airplane began to climb, he diverted his attention, and when he looked back, he could not locate it. Moments later he observed a rising column of smoke.
The airboss, who cleared the airplane for takeoff, reported no distress calls or abnormal communications. Several witnesses reported that a "puff of smoke" exited the airplane's exhaust before taxi and that the airplane seemed "slow" during climbout. A witness near the departure end of the runway stated that the airplane did not appear to be climbing as quickly as other jet-powered airplanes he had observed. He further stated that the airplane made a right turn and pitched up to gain altitude, and "the engine failed." The airplane subsequently entered a "sliding turn" and descended nose first toward the ground.
Personnel Information
The pilot, age 61, held an airline transport pilot certificate with ratings for airplane single- and multiengine land. He also held type ratings for Cessna CE-525- and CE-525S-series airplanes and had private pilot privileges in single-engine sea airplanes. His personal flight logs were not located. He reported 6,000 hours of total flight experience, with 40 hours accumulated during the previous 6 months, on his most recent FAA medical examination on December 23, 2014, which resulted in a limited second-class/full third-class special issuance medical certificate. A flight instructor reported that the pilot satisfactorily completed a flight review and pilot proficiency check in the airplane on April 16, 2015.
Aircraft Information
The single-engine, two-seat, high-performance airplane was manufactured in Czechoslovakia as a basic and advanced military jet trainer. It was equipped with an Ivchenko AI-25TL turbofan engine with a takeoff thrust rating of 3,792 pounds. According to FAA airworthiness records, the airplane was manufactured in 1983 and purchased by the pilot on October 7, 1999. It was issued an FAA experimental special airworthiness certificate in the exhibition category on October 23, 1999.
The airplane was maintained under an FAA-approved maintenance program. The most recent condition inspection was performed on April 2, 2015. The pilot's friend reported that the airplane had been flown about 13 to 15 times and had accumulated about 15 to 18 hours since that inspection. At the time, the airplane had been operated for about 1,550 total hours and about 325 hours since purchase. The engine, new when installed on March 27, 2001, had about 325 hours. The airplane was not flown between October 25, 1999, and the date the new engine was installed.
Meteorological Information
At 1635, weather conditions at Campbell County Airport (JAU), about 24 nautical miles east-southeast of the accident site, included wind from 310° at 5 knots, visibility 10 statute miles, clear sky, temperature 23°C, dew point 4°C, and an altimeter setting of 29.85 inches of mercury.
Airport Information
Scott Municipal Airport (SCX) in Oneida, Tennessee, served as the departure point. The airshow, Wings Over Big South Fork, was being held on the day of the accident.
Wreckage and Impact Information
The airplane impacted trees about 2 miles west of the departure end of runway 23 in the Big South Fork National River and Recreation Area. The airplane was severely fragmented and partially consumed by a postimpact fire. A debris path began around a group of about 75-ft-tall broken trees and continued on a magnetic heading of about 120° for about 325 ft over sloped, uneven terrain to the engine.
Portions of all major airframe parts, including all flight controls, were identified in the debris path. The fuselage and both wings were fragmented, and the empennage was separated. The vertical stabilizer and rudder were separated, and the rudder trim tab was separated from the rudder. The left and right elevators remained attached to the horizontal stabilizer, which displayed crushing damage and tearing consistent with tree and ground impacts. The left aileron remained attached to the outboard portion of the left wing, and the right aileron was separated. Both wing tip fuel tanks were separated. The postimpact condition precluded confirmation of flight control continuity.
The airplane was equipped with ejection seats. One ejection seat rocket motor was found discharged, and one parachute was located in the debris path; however, its respective envelope was not inflated.
The engine was impact and fire damaged. It was complete from the inlet case's front flange to the exhaust duct's rear flange. Visual examination of the last stage turbine assembly did not reveal damage consistent with an internal catastrophic failure. The gearbox was missing from the engine. A small section of the gearbox housing, which included three internal spur gears with no apparent teeth damage, was recovered among the debris.
Additional examination after recovery revealed that all fan ducts were in place, except for an area on the top of the engine between the intermediate case and the rear fan duct that was partially burned away. There was no forward-to-aft linearity of soot and burn patterns, consistent with a postimpact fire. All 1st, 2nd, and 3rd stage fan blades were in place. Five 1st stage fan blades were separated up to 2 inches above their blade root platforms, and the remaining fan blades were bent in the midspan area opposite the direction of rotation. None had soft body or hard body impact damage. The 3rd stage fan blade shroud contained imprints of the blades, with no circumferential rub marks. The fuel control throttle pointer indicated 30 (0-110 scale), and the high-pressure compressor variable stator vane indicator was at 17 (0-30 scale). The fuel control unit remained attached to the engine but sustained both impact and thermal damage.
Medical and Pathological Information
The Knox County Regional Forensic Center performed an autopsy on the pilot. According to the report, the cause of death was "multiple blunt force injuries following airplane crash." Review of the pilot's medical history revealed a history of hypertension, high cholesterol, and severe coronary artery disease, which required surgery in 1997. He reported these diagnoses to the FAA, as well as the use of medications including atorvastatin and atenolol.
Toxicological testing by NMS Labs on specimens from the pilot identified 0.064 gm/dl of ethanol and caffeine in muscle tissue. Ethanol is an intoxicant that may also be produced in body tissues by microbial activity after death. Testing by the FAA Bioaeronautical Science Research Laboratory was limited by the lack of available blood, urine, or vitreous. No ethanol was identified in muscle; however, diphenhydramine and metoprolol were detected in muscle and brain tissue. Metoprolol is a beta-blocking agent similar to atenolol used to treat high blood pressure and reduce the risk of recurrent heart attacks. Diphenhydramine is a sedating antihistamine used to treat allergy symptoms and as a sleep aid.