Cessna 182 N5700B accident near Aberdeen, Idaho

Probable cause

The pilot's failure to use carburetor heat while operating in conditions conducive to carburetor icing, which resulted in a partial loss of engine power and a subsequent forced landing and nose-over.

NTSB analysis

The pilot was conducting a personal, cross-country flight. During the flight, the airplane encountered light drizzle and reduced visibility. After continuing for a few minutes in these conditions while about 2,000 ft above ground level, the pilot decided to initiate a right turn and divert from his original destination. As the airplane exited the turn, the engine “stuttered” a few times and eventually lost power. Despite the pilot's attempts to restore engine power, during which he did not apply carburetor heat, the engine would only run roughly and inconsistently. He then decided to divert to another airport that was closer to the airplane’s position. As he was about to reattempt to restore engine power, the engine developed partial power; however, it was insufficient to sustain flight. Realizing the airplane could not reach the airport, he chose to conduct an emergency landing to an open field. During the landing roll, the main landing gear dug into dirt, and the nosewheel then hit the ground hard and collapsed. Subsequently, the nose dug into dirt, and the airplane nosed over, which resulted in substantial damage to the vertical stabilizer, rudder, and fuselage.

Examination of the engine revealed no evidence of preaccident mechanical malfunctions or failures that would have precluded normal operation. The atmospheric conditions that existed around the time of the accident were conducive to the formation of serious carburetor icing at cruise power. Therefore, it is likely the engine lost power due to the accumulation of carburetor ice, which resulted from the pilot’s failure to use carburetor heat.

Text from the NTSB. Open the NTSB docket for WPR18LA149 for the full record.