Accident Overview
On September 23, 2024, at approximately 1357 central daylight time, an Aviat Aircraft Inc. S-1-11B airplane, registration N5111B, was substantially damaged when it crashed into the Cumberland River near Chapmansboro, Tennessee. The commercial pilot sustained fatal injuries. The airplane was operated as a personal flight under Title 14 Code of Federal Regulations Part 91.
Flight and Maneuvers
According to the pilot’s spouse, the pilot intended to practice aerobatic routines in preparation for seeking a qualification to perform in airshows. FAA ADS-B flight track data indicated that the airplane departed southeast from Whifferdill Airport (TN77) at about 1345. The flight track showed that after overflying the airport twice, the airplane spent the remainder of the flight about one mile south of the airport within the waivered aerobatic practice box, performing low-altitude maneuvers between 400 and 2,000 ft above ground level (agl). The final ADS-B data point was recorded at 1357, 12 minutes after takeoff.
Witness and Video Evidence
A witness on a kayak on the Cumberland River, about half a mile south of the accident site, reported that the airplane had been performing various aerobatic maneuvers at low altitude. The witness noted that the engine sound would go quiet and then “rev” back up during the maneuvers. The witness recorded several videos, including a two-minute video capturing the final moments of the flight. In the last seconds of the video, the airplane entered a climb and completed a 4-point aileron roll. It continued climbing briefly before leaving the camera’s view. ADS-B data indicated that the altitude for this final maneuver ranged between 700 and 1,800 ft agl. The airplane reappeared on video in an orientation consistent with an inverted flat spin, rotating slightly nose left, and descending rapidly toward the river. An increase in engine rpm was heard during the final seconds, and engine noise continued throughout the spin after the airplane disappeared below the tree line.
Aircraft Information and Maintenance
According to FAA records, the pilot purchased the airplane on June 3, 2022. An annual inspection was performed shortly before the purchase on April 19, 2022, at a tachometer time of 2,398.78 hours. Two subsequent annual inspections were conducted: one on July 7, 2023, at 2,408.03 hours, and the most recent on August 15, 2024, at 2,447.29 hours. The airplane had accumulated at least 39.3 hours since the purchase, and the pilot’s spouse stated that the pilot was the only person who had flown the airplane since the purchase.
Weather and Airport Conditions
The witness on the river reported a slight breeze with no significant weather. Routine surface observations from the surrounding area confirmed no clouds or precipitation at the time. A hurricane was tracking toward the area from the south, expected to bring rain later in the week. The pilot’s spouse recalled that the pilot was “trying to get his first practice flight in before the rain came the next day.” The pilot stored and operated the airplane out of TN77, a private-use fly-in community and airport. ADS-B data showed departure from Runway 15, a 2,000 ft turf runway. The Whifferdill practice aerobatics box was active with an associated NOTAM. The box was located immediately south of the airport over the Cumberland River, with each boundary 1 mile in length, extending from 500 ft agl to 3,500 ft mean sea level.
Impact and Wreckage Examination
The airplane impacted shallow water in the Cumberland River about 150 ft from the last observed ADS-B position. It was found inverted and partially submerged. A small fuel slick was evident on the water. The wreckage was recovered and transported to a salvage facility for examination. The airplane remained intact except for the canopy, which was not recovered. Flight control continuity was confirmed from the cockpit to all flight control surfaces. The top of the rudder and vertical stabilizer were bent 90° to the right. The top of the airframe exhibited downward crushing, while the bottom of the fuselage structure was relatively free of damage. The landing gear remained intact with little damage. The fuel header tank was breached on impact.
Engine and Propeller Examination
The engine remained intact and was free of major impact damage but contained a substantial amount of mud and debris, consistent with submersion. Crankshaft and camshaft continuity and thumb compression were observed on all cylinders. Top and bottom spark plugs exhibited normal combustion signatures, and the oil filter showed no evidence of metal contamination. The left magneto produced spark when its input driveshaft was rotated by hand; the right magneto was too waterlogged to produce spark. All three propeller blades had splintered and separated near the propeller hub on impact.
Medical and Toxicology Information
An autopsy performed by the Office of the Medical Examiner, District 23, Nashville, Tennessee, determined that the cause of death was blunt force injuries of the head, neck, torso, and extremities. Toxicology testing by the FAA Forensic Sciences Laboratory detected the high blood pressure medication lisinopril in the pilot’s urine, which was not generally considered impairing.