What happened
On July 22, 2016, a Stinson 108-2 was conducting a cross-country flight from Mankato Municipal Airport (MKT) to Oshkosh, Wisconsin. The flight departed MKT at approximately 1130 central standard time. While cruising at 1,000 feet AGL, the engine power decreased from 2,350 RPM to 2,100 RPM. The pilot applied carburetor heat for several seconds before returning it to the off position.
As the aircraft continued toward Dodge Center Airport (TOB), the power loss persisted for approximately 10 miles before further degradation occurred. The pilot attempted to land on a road near Dodge Center, but the aircraft landed in a field and rolled over. The aircraft, N8019K, sustained substantial damage. Of the 3 occupants on board, the pilot and one passenger sustained minor injuries, while one passenger was not injured.
The investigation
An FAA inspector examined the wreckage at the accident site and found no mechanical anomalies. Meteorological data from the Dodge Center airport indicated a temperature of 31 degrees Fahrenheit and a dew point of 24 degrees Fahrenheit. According to the Icing Probability Chart, these conditions were susceptible to light carburetor icing during cruise or descent power.