Accident Overview
On May 21, 2023, at approximately 1435 central daylight time, a Piper PA-28-180 (registration N9139J) sustained substantial damage during a forced landing near Lancaster, Tennessee. The private pilot and one passenger suffered minor injuries. The flight was operated under Title 14 Code of Federal Regulations Part 91 as a personal flight.
Flight Sequence
The pilot reported that after landing at John C Tune Airport in Nashville, Tennessee, he had the fuel tanks topped off and performed a preflight inspection, including checking the wing tank sump drains. No issues were noted. Departing for Seymour Air Park in Seymour, Tennessee, the flight proceeded uneventfully for about 20 to 25 minutes. While cruising at 3,500 feet mean sea level with visual flight rules flight following, the engine abruptly lost power, running roughly—described by the pilot as 'like it were running on 2 cylinders.' The airframe shook, and the airplane began losing altitude. The pilot activated the auxiliary fuel pump, switched fuel tanks, checked the magnetos, and applied carburetor heat, but none of these actions restored power. The nearest airport was 17 nautical miles to the south; the pilot observed several large fields nearby and informed the air traffic controller of the engine failure, then declared he would land in a field. He executed a forced landing with full flaps. At touchdown, the nose landing gear collapsed, and the airplane pitched nose-down. It came to rest upright in a nose-down attitude, with substantial damage to the engine mount.
Post-Accident Examination
Recovery personnel noted the nose landing gear was collapsed aft. Approximately 45 gallons of fuel were drained from the tanks, with no contamination found. The engine was examined after recovery, revealing a fractured exhaust valve on the No. 2 cylinder. The valve head was missing, and damage was present on several areas of the piston top. The No. 2 cylinder and fractured valve stem were sent to the National Transportation Safety Board Materials Laboratory for detailed examination.
Metallurgical Findings
Laboratory examination determined that the valve fractured due to fatigue cracking initiated at multiple locations along the stem exterior surface. As the cracking progressed across most of the stem cross-section, the head separated. The resulting damage was consistent with the loose fragment battering repeatedly against the cylinder and piston surfaces. The valve exhibited thick lead oxide deposits, surface oxidation, and a coarsened microstructure, indicating exposure to elevated temperatures.
Maintenance History
Review of engine maintenance records showed that the engine had accrued about 1,915 hours and 45 years since its last overhaul; the No. 2 exhaust valve had been replaced 1,635 hours and 39 years prior; and the valve guides had been replaced 1,218 hours and 34 years earlier. According to Lycoming Service Instruction No. 1009BE (not mandatory for Part 91 operators), all engine models should be overhauled within 12 calendar years of first service or last overhaul.