Accident Details
On April 14, 2023, at approximately 1440 eastern daylight time, a Cessna 177RG, registration N7542V, was substantially damaged during an accident near Crestview, Florida. The pilot sustained serious injuries. The airplane was operated as a personal flight under Title 14 Code of Federal Regulations Part 91.
The pilot reported departing Destin Executive Airport (DTS), Destin, Florida, to practice RNAV and ILS approaches in visual meteorological conditions at Bob Sikes Airport (CEW), Crestview, Florida. The flight to CEW was uneventful. Shortly after being cleared for the first practice approach, the pilot heard a loud noise from the propeller hub. The propeller immediately began to shudder violently and oscillate in a semi-oval pattern. The fuselage vibrated intensely, and oil appeared on the propeller hub, subsequently coating the windshield and impairing visibility. The pilot shut down the engine and identified a field for a forced landing. However, upon approach, he observed obstacles and a marsh. He kept the landing gear retracted and landed in an area of cut trees. After touchdown, the airplane slid approximately 100 feet before coming to a stop.
Examination Findings
An FAA inspector examined the wreckage at the accident site. The engine firewall was buckled, with complete structural failure at the engine mounts. The left outboard wing section was bent upward, and the vertical stabilizer leading edge and horizontal stabilator were buckled. The lower fuselage was damaged, and the landing gear was fully retracted. Oil was present in the engine, but the engine was tilted forward in its mount, preventing an accurate oil quantity determination. Evidence of oil leakage was found on the right side of the aircraft.
The wreckage was recovered to a storage facility for further examination. During engine tear-down, the propeller was rotated manually through 90 degrees of travel before it stopped and could not be rotated further. The oil suction screen contained approximately one teaspoon of metallic flakes, and metal particles were present throughout the pleats of the oil filter element.
The No. 3 cylinder was removed, and the No. 3 connecting rod beam was cut to access the rear engine interior. Damage to the cylinder skirts of cylinders Nos. 1, 2, and 4 prevented their removal. The No. 1 cylinder barrel was cut and removed. The No. 1 connecting rod was found separated from the No. 1 crankshaft rod journal and damaged from impact with internal engine components. The No. 1 rod cap was damaged and found inside the crankcase. Two portions of the No. 1 connecting rod were also found inside the crankcase with rod bolt holes. Both rod bolt threaded ends were found in the crankcase; no rod nuts were observed on these ends. A portion of a threaded rod nut was observed inside the crankcase. Fragments of the No. 1 rod bearings were found inside the crankcase. The No. 1 crankshaft rod journal did not exhibit scoring or discoloration consistent with overheating, and no overheating indications were observed on other rod journals or crankshaft journals.
Maintenance History
A review of the aircraft maintenance logbooks revealed that, as of the last annual inspection on September 16, 2022, the engine had accumulated 1,624.61 hours since its last overhaul. The pilot, who owned the airplane, purchased it on September 10, 2021. The engine overhaul was completed on February 28, 1993, more than 30 years before the accident. According to Lycoming Service Instruction No. 1009BE, dated April 24, 2020, all engine models are to be overhauled within 12 calendar years of the date they first entered service or of last overhaul to mitigate engine deterioration with age, including corrosion and degradation of non-metallic components.