N139RTGulfstream Aerospace GVI (G650ER) · 2020

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 the provisions of 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 that was being held on the day of the accident. Witnesses reported that the pilot was scheduled to be the final performer in the airshow.

A friend of the pilot, who had flown the airplane about 1 week before the accident and assisted the pilot on the day of the accident, reported that he removed the safety pins for the front cockpit ejection seat, filled the airplane's smoke system oil tank, and observed the pilot perform a full power engine check and smoke system check before the takeoff from runway 23. He further stated that the takeoff "appeared normal in all respects." As the airplane began to climb, he diverted his attention to the spectators, and when he looked back for the airplane, 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 from the pilot before the accident. Several witnesses reported that a "puff of smoke" exited the airplane's exhaust before the airplane's taxi to the runway and that the airplane seemed "slow" during climbout. A witness located 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 previously 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.

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.

The pilot's 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 Federal Aviation Administration (FAA) medical examination, which was conducted on December 23, 2014, and resulted in the issuance of 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.

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, which had 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. Review of maintenance records revealed that the airplane's 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 of flight time since the condition inspection.

At that time, the airplane had been operated for about 1,550 total hours and about 325 hours since it was purchased by the pilot. The engine, which was new when it was installed on March 27, 2001, had been operated for about 325 hours. The airplane was not flown between October 25, 1999, and the date the that new engine was installed.

At 1635, the weather conditions reported at Campbell County Airport (JAU), which was located about 24 nautical miles east-southeast from the accident site, included wind from 310° at 5 knots, visibility 10 statute miles, clear sky, a temperature of 23°C, a dew point of 4°C, and an altimeter setting of 29.85 inches of mercury.

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, which had 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. Review of maintenance records revealed that the airplane's 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 of flight time since the condition inspection.

At that time, the airplane had been operated for about 1,550 total hours and about 325 hours since it was purchased by the pilot. The engine, which was new when it was installed on March 27, 2001, had been operated for about 325 hours. The airplane was not flown between October 25, 1999, and the date the that new engine was installed.

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 parts of the airframe, which included all the 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 from the empennage. The rudder trim tab was separated from the rudder. The left and right elevators remained attached to the horizontal stabilizer; however, the horizontal stabilizer and both elevators 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 of the airframe 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 any 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 airplane debris.

Additional examination of the engine after it was recovered from the accident site revealed that all the 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 the soot and burn patterns, consistent with a postimpact fire. All of the 1st, 2nd, and 3rd stage fan blades were in place in their respective disks. 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 of the 1st stage fan blades had any soft body or hard body impact damage. The 3rd stage fan blade shroud contained imprints of the 3rd stage fan 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.

The Knox County Regional Forensic Center, Knoxville, Tennessee, performed an autopsy on the pilot. According to the autopsy report, the cause of death was "multiple blunt force injuries following airplane crash."

Review of the pilot's medical history revealed that he had a history of hypertension, high cholesterol, and severe coronary artery disease, which required surgery in 1997. He reported all those diagnoses to the FAA, as well as the use of several medications, including atorvastatin and atenolol.

Toxicological testing performed by NMS Labs on specimens from the pilot at the request of the medical examiner identified 0.064 gm/dl of ethanol and caffeine in muscle tissue. Ethanol is an intoxicant commonly found in beer, wine, and liquor that acts as a central nervous system depressant. Ethanol may also be produced in body tissues by microbial activity after death.

Toxicology testing performed on specimens from the pilot by the FAA Bioaeronautical Science Research Laboratory, Oklahoma City, Oklahoma, was limited by the lack of available blood, urine, or vitreous for testing. 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 that is 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.