Accident Overview
On March 17, 2024, at 0825 eastern daylight time, a Beech A36 airplane, registration N729CW, was substantially damaged during an accident near Blackshear, Georgia. The aircraft was operating as a personal flight under Title 14 Code of Federal Regulations Part 91. The private pilot and two passengers reported no injuries.
Pilot Report
The pilot stated that while climbing through 11,000 ft mean sea level, he experienced a reduction in engine power and an inability to continue climbing. He observed a loss of oil pressure, followed by rough engine operation and eventual seizure. The pilot executed a forced landing onto a rural road, during which the airplane struck a tree, causing substantial damage to the right wing and engine mounts.
Post-Accident Observations
First responders photographed the engine, which showed a large amount of residual oil on the inside of the engine cowling. The pilot reported that before departure he checked the oil level and added 1 quart to the existing 11 quarts, totaling 12 quarts.
Engine and Turbocharger Examination
The airplane was moved to a secured facility, where salvage personnel removed the engine and turbocharger for examination at Continental Aerospace Technologies in Mobile, Alabama. The mechanic who removed the turbocharger noted no loose fittings or oil leaks. During a later visit by NTSB personnel, the turbocharger’s oil scavenge line was found clear of debris, and no leaks or residual oil were observed on the aircraft belly.
Disassembly of the turbocharger revealed its internal components, including the rotor assembly, bearings, and housing, were coated with a thick layer of oil and debris but showed no damage. No mechanical deficiencies were found that would have prevented normal operation.
Examination of the engine showed a large hole in the top of the crankcase between the No. 3 and No. 4 cylinders. The crankshaft was seized and could not be rotated. The oil filler cap was secure, and the oil sump contained a large amount of metallic debris, including a connecting rod and lifters. The oil scavenger pump and oil pump were manually rotated and disassembled, revealing no mechanical deficiencies.
Further disassembly revealed multiple failed and heavily damaged connecting rods. Indications of overheating consistent with oil starvation were evident on the No. 2 through No. 5 connecting rods. The No. 4 and No. 5 connecting rods were the most damaged and had separated from the crankshaft. The camshaft was sheared, and the No. 4 push rods were bent. All oil ports were clear except the No. 5 connecting rod journal, which was blocked, consistent with welding from heat during the failure sequence. Internal damage prevented rotation of the crankshaft and establishment of compression or engine timing.
Additional Information
The airplane was equipped with a Garmin GEA-24 engine indicating system, which lacked recording capability; no engine data was recovered.
Maintenance logs indicated that at the time of the accident the engine had accumulated 2,748 total operational hours. It had undergone a major overhaul 871 hours prior.