Primary finding
Probable cause
The partial loss of engine power for reasons that could not be determined.
Investigator assessment
Analysis narrative
The pilot reported that the airplane’s engine did not respond to a commanded power increase while maneuvering for spacing due to aircraft traffic. He subsequently made a forced landing to a field. The airplane sustained substantial damaged to the forward fuselage when it struck a terrace in the field. A postaccident engine run was conducted and although the test was limited due to the bent propeller, the engine exhibited no anomalies during the engine run. The possibility of carburetor icing existed based on the atmospheric conditions present at the time of the accident, but the pilot stated that he had carburetor heat applied during the event. The carburetor heat system worked normally during the engine run. Based on the available information, the reason for the partial loss of engine power could not be determined.
Source record
Factual narrative
On January 5, 2023, about 1120 central standard time, a Cessna 182M airplane, N71494, was substantially damaged when it was involved in an accident near, Council Bluffs, Iowa. The pilot and passenger were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. According to the pilot, he was flying to Council Bluffs Municipal Airport (CBF) to discuss having avionics work performed on the airplane. There was another airplane on a practice VOR-A instrument approach to CBF and the pilot recognized there was going to be a conflict, so he elected to perform a 360° turn to allow for increased spacing. At this time, he had the airplane configured with 10° flap, with the manifold pressure at 13 inches of mercury, and carburetor heat on. As the airplane entered the turn, he increased power to 17 inches of mercury and held his altitude at 1,900 ft msl. As the airplane completed about half of the 360° turn, he added power to maintain altitude and there was no response from the engine. The airplane was about 500 ft above ground level and the pilot stated that he did not have time to restart the engine. He said that he focused on locating a suitable landing area and controlling the airplane. The pilot stated that he did not turn off the carburetor heat during the turn or after the engine stopped producing power. There was about 38 gallons of fuel on-board the airplane and the fuel selector was on BOTH. The pilot executed a forced landing to a harvested soybean field. During the landing, the airplane struck a terrace in the field, which damaged the forward fuselage. After the accident a test run of the engine was conducted. The engine started normally and idled smoothly. Once warmed up, the engine was advanced to 1,500 rpm and the engine continued to run smoothly. A magneto check was performed indicating about 75 rpm drop on each magneto. The carburetor heat was activated and indicated a drop in rpm when applied. The engine rpm was not advanced above 1,500 rpm due to concerns about the bent propeller. The weather conditions at the time of the accident included a temperature of -1° C, and dewpoint of -7° C. These were in a range for potential carburetor icing at glide and cruise power.