N23473

On November 10, 2016, about 0540 eastern standard time, a privately owned and operated Cessna 150H, N23473, nosed over during a forced landing in a field near Snow Hill, North Carolina. The private pilot and one passenger were not injured, and the airplane was substantially damaged. Visual meteorological conditions prevailed at the time and no flight plan was filed for the personal flight that was conducted under the provisions of 14 Code of Federal Regulations Part 91. The flight originated about 35 minutes earlier from Raleigh East Airport (W17), Knightdale, North Carolina, and was destined for Kinston Regional Jetport at Stallings Field (ISO), Kinston, North Carolina.The pilot stated that he performed a preflight inspection of the airplane and no discrepancies were reported. The flight departed with about 13 gallons of automotive fuel, and about 35 minutes after takeoff during cruise flight at 3,000 ft mean sea level, the engine suddenly lost power. He immediately applied carburetor heat which remained on, and about 1 to 2 times, the engine surged to full power but, "immediately died back off." Attempts to restore engine power were unsuccessful. He turned to fly to a nearby airport, but executed a forced landing in a field. While descending, he reported the propeller continued to windmill. After the nose landing gear contacted the ground, the airplane nosed over.

Examination of the inverted airplane was performed the same day by a Federal Aviation Administration (FAA) inspector. The examination revealed no visible fuel in the left fuel tank, while fuel was found in the right fuel tank. The carburetor bowl contained a normal amount of uncontaminated fuel, and the inlet screen was clean. The float assembly moved easily with no binding noted. There were no marks on the float indicating it had been rubbing against the interior surface of the carburetor bowl. The needle valve and seat operated normally with no contamination or binding, and the venturi of the carburetor appeared satisfactory. The fuel strainer also contained a normal amount of uncontaminated fuel, as did the flexible fuel hose from the fuel strainer to the carburetor. Examination of the air induction and exhaust systems revealed no evidence of blockage. Engine control continuity was confirmed from the cockpit to each respective control in the engine compartment; the controls were properly rigged. The carburetor heat door was in the position to apply carburetor heat with no discrepancies noted. The magnetos which were tightly secured to the accessory case, were operated by hand actuation and produced spark at all ignition leads; the magnetos were retained for further examination. Inspection of the ignition system revealed the spark plugs were "…dark charcoal around the outer perimeter and a light gray to whitish on the ground and center electrodes, very slight carbon buildup in the recessed center electrode area was observed…." Operational testing and disassembly inspection of the ignition switch revealed no discrepancies. Examination of the P-leads revealed the shielding of the left magneto was cracked, however, there was no path to ground for either p-lead. Crankshaft, camshaft, and valve train continuity was confirmed, and adequate oil supply remained.

According to the pilot who was present for recovery, after the airplane was uprighted the same day, fuel began leaking from the left fuel vent line. He estimated that the left fuel tank contained about 4 to 5 gallons of fuel.

Operational testing of the magnetos was performed at a FAA approved repair station; no evidence of preimpact failure or malfunction was noted.

A surface weather observation at Wayne Executive Jetport Airport (GWW) at 0545, indicated the temperature and dewpoint were 07° and 04°C, respectively. The accident site was located about 110°and 8 nautical miles from GWW.

According to Federal Aviation Administration (FAA) Special Airworthiness Information Bulletin (SAIB) CE-09-35 related to carburetor ice, the environmental conditions at the time were conducive for serious icing at cruise power.