Forced Landing After Engine Seizure During Cruise (N4540H)

Maintenance and Preflight Inspection Before the accident flight, the pilot stated that the airplane had received an oil and filter change, along with replacement of the oil temperature and oil pressure gauge. The pilot added one quart of oil and observed the mechanic add five additional quarts. After an engine run, the dipstick indicated 4.5 quarts of oil. The pilot then topped off the fuel and completed a preflight inspection, noting no anomalies. All required checklist items were completed before taxiing out and departing. ## In-Flight Engine Failure During cruise flight at 2,500 feet and 95 mph, the pilot observed changes in oil pressure and oil temperature. The oil pressure rose above 50 psi, then dropped below 40 psi, reached 0 psi, and the engine quit and seized. The pilot initiated a forced landing, maneuvering the airplane below some wires on final approach. The aircraft landed on a road and rolled into a grassy area. ## Collision Sequence The airplane collided with a bump, bounced, and touched back down. The pilot saw a tree to the right and applied left rudder to avoid it, but the right wing struck the tree and separated. The airplane turned right, and the left wing collided with another tree. The aircraft then turned left and struck a third tree head-on, coming to a complete stop. ## Post-Accident Examination Recovery personnel examined the engine. The oil temperature and oil pressure lines were attached and undamaged. The oil dipstick cap was separated from the dipstick, and its spring was found lodged in an engine mount on the right side of the firewall. No oil was present on the engine case halves or in the engine compartment. Upon disassembly, the No. 1 cylinder connecting rod had separated from the rod journal. The No. 1 rod journal and connecting rod showed heat discoloration, and the rod cap bearing was partly melted and displaced. The No. 1 rod journal oil inlet was partly melted and blocked. No metal particles were found in the oil filter or oil screen. The rear accessory gears and crankcase halves were dry and not coated with oil. Fifteen ounces of black oil were drained from the oil sump, and a small amount of clear oil was observed in the valve covers.