Events Leading to the Emergency Landing
The pilot of a single-engine aircraft was on a cross-country flight when, after approximately 1.5 hours, the engine began to run rough. In an attempt to correct the roughness, the pilot applied carburetor heat. Immediately after applying carburetor heat, the engine quit. The pilot then turned off the carburetor heat, but engine power could not be restored.
Emergency Landing
Faced with a complete loss of engine power, the pilot planned an emergency landing on an interstate highway, between two overpasses. The pilot delayed lowering the landing gear until the aircraft had cleared high lines along the approach path. The aircraft subsequently touched down with the landing gear retracted, resulting in a gear-up landing.
Environmental Conditions
The outside air temperature was 48 degrees Fahrenheit, with a dew point of 47 degrees Fahrenheit. According to icing probability charts, these conditions were conducive to the formation of carburetor ice.