Accident Sequence
On June 20, 2015, at about 1100 central daylight time, a Cessna 150L (registration N17292) sustained substantial damage when it nosed over during a forced landing following a loss of engine power near Carthage, Indiana. The pilot was not injured. The airplane was registered to and operated by a private individual under 14 CFR Part 91 as a personal flight. Visual meteorological conditions prevailed, and the flight was not on a flight plan. The local flight originated from Small Airfield (IN81) in Carthage, Indiana.
The pilot reported that after performing a pre-flight inspection and run-up, he proceeded to takeoff. During the initial climb, the engine lost power. The engine speed decreased and the pilot could not maintain altitude. He attempted to adjust the fuel mixture and throttle with no effect. He applied carburetor heat, which caused the engine to run rougher, but he left it on. The pilot subsequently made an off-airport landing to a corn field. During the landing roll, the nose landing gear dug into soft mud and the airplane nosed over.
Post-Accident Examination
The pilot/owner disassembled the airplane and removed it from the field before notifying the National Transportation Safety Board or the Federal Aviation Administration (FAA). On January 15, 2016, FAA inspectors examined the airplane. The fuselage was present; the owner had removed the wings, doors, engine, radios, and instruments and sold them. Inspection of the fuselage revealed a torn engine mount, missing nose gear, wrinkled lower firewall, missing windshield, twisted left horizontal stabilizer, and damage to the top of the vertical stabilizer and rudder.
The engine had been sold to an individual who hired a mechanic to overhaul it. The mechanic stated the engine was improperly assembled with non-certificated parts. He reported that cylinder hold-down nuts were not properly tightened, crankcase parting flange hardware was loose, connecting rod cap bolts were not cotter-pinned, camshaft gear and crankshaft gear attaching hardware were not safety-wired, the vacuum pump drive gear was not installed, and the camshaft and lifters were not certificated parts. The magnetos were worn out. As a result, the case halves were not repairable, the magnetos were not serviceable, the camshaft and lifters were not certificated, the crankshaft was damaged, and two cylinders were not serviceable. The mechanic opined that the reassembler was unfamiliar with manufacturer's maintenance or overhaul procedures and regulatory guidance.
Maintenance records were not available; FAA inspectors reported that the owner destroyed the records before FAA involvement.
Weather Conditions
At 1053, the reported weather 15 miles southwest of the accident site included a temperature of 24°C and dew point of 21°C. According to a carburetor icing probability chart, these conditions were in the range of susceptibility for moderate carburetor icing at cruise power and severe icing at descent power. FAA Special Airworthiness Information Bulletin CE-09-35, "Carburetor Icing Prevention", states that a drop in engine speed in fixed-pitch propeller airplanes is a warning sign of potential carburetor icing, and application of carburetor heat may cause temporary engine roughness while ice melts.