On July 23, 2021, about 1520 central daylight time, an Aeronca 7AC airplane, N83365, was substantially damaged when it was involved in an accident near Harrah, Oklahoma. The pilot and pilot-rated-passenger sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 instructional flight.

The pilot-rated-passenger stated that, during the preflight inspection, he and the pilot noted that the carburetor heat control was not installed. They completed a short ground taxi and engine runup with no anomalies noted. Shortly after takeoff, the engine rpm surged then decreased such that the airplane was unable to maintain altitude. The pilot made a forced landing to a field and the airplane nosed over. The passenger reported that he had experienced carburetor ice many times in the past and believed that the loss of engine power was the result of carburetor ice.

The pilot, who was also the airplane owner, stated that, about 150 ft above ground level after takeoff, the airplane was sluggish and the engine surged between 2,000 and 2,400 rpm, then experienced a loss of power. They made a forced landing to a field of tall grass and soft soil and the airplane nosed over. The pilot reported that there were no mechanical malfunctions or anomalies that would have precluded normal operation. The pilot provided photos that showed substantial damage to the horizontal stabilizer and rudder.

The atmospheric conditions at the time of the accident were conducive to the development of serious carburetor icing at glide and cruise power. Postaccident photos of the airplane revealed that the carburetor heat control was missing.