ANC15LA046

The private pilot was conducting a personal cross-country flight. The pilot reported that he was flying the airplane over an inland waterway when the engine began surging. The pilot switched fuel tanks, but the engine continued to surge and then lost total power. The pilot subsequently executed a forced landing on a highway, which resulted in substantial damage to the wing. After the accident, the pilot and a mechanic started the airplane, and the engine ran smoothly at various power settings. The atmospheric conditions at the time of the accident were conducive to the accumulation of serious carburetor icing at glide power and moderate icing at cruise power. Therefore, it is likely that carburetor ice formed, which caused the engine to lose power, and that the pilot did not apply carburetor heat.

On July 4, 2014 about 1943 Alaska daylight time, a Cessna 182 airplane, N4861D, sustained substantial damage during a forced landing on a highway about 8 nautical miles south of Merrill Field, Anchorage, Alaska. The airplane was registered to, and operated by, the pilot as a visual flight rules (VFR) personal flight under the provisions of 14 Code of Federal Regulations Part 91. The pilot and two passengers were not injured. Visual meteorological conditions prevailed for the flight that originated from Seward Airport, Seward, Alaska. In a telephone conversation with the National Transportation Safety Board investigator-in-charge, the pilot stated that while flying across the Turnagain Arm, an inland waterway, the engine began surging. He switched from the right fuel tank to the left fuel tank, but the engine continued to surge and was followed by a complete loss of engine power. The pilot performed a forced landing to a highway, which resulted in substantial damage to the wing. Following the accident the aircraft was moved off the highway to a parking lot where the pilot and a mechanic started the engine; it ran smoothly at various power settings. About 15 gallons of fuel was drained from the main fuel tanks before the wings were removed. No damage to the fuel lines were noted during the removal of the wings. Examination of the wing tanks did not reveal any anomalies that would have precluded fuel from reaching the engine. The closest weather reporting facility was the Merrill Field Airport, Anchorage, about 8 miles north of the accident site. At 1953, an aviation routine weather report (METAR) from the Kenai Airport was reporting in part: wind from 300 degrees at 3 knots; sky condition overcast 7,000 feet; visibility 10 statute miles; temperature 63 degrees F; dew point 52 degrees F; barometric pressure 30.17 inHg. The carburetor icing probability chart included in Federal Aviation Administration Special Airworthiness Information Bulletin No. CE-09-35, Carburetor Icing Prevention, indicated that the airplane was operating in an area that was associated with a risk of carburetor ice formation, at glide and cruise power settings. The pilot did not complete the NTSB form 6120 Pilot/Operator Aircraft Accident/Incident Report as requested.