What is an indication of carburetor icing?

The indication of carburetor icing is often characterized by a loss of RPM and engine roughness. This phenomenon occurs when moisture in the air freezes within the carburetor, causing disruptions in fuel-air mixture flow. As the ice builds up, it restricts airflow into the engine, which can lead to a decrease in power output and stability. Pilots may notice a drop in engine RPM, as the engine struggles to maintain performance due to the inadequate mixture of fuel and air caused by the icing. Additionally, the roughness in engine performance results from the inconsistent combustion conditions caused by the blocked airflow and fuel delivery.

While other options may convey different aspects of engine performance, they don't accurately represent the characteristic symptoms of carburetor icing. Increases in RPM or stable engine performance would not typically coincide with an icing event, and a decrease in fuel consumption does not directly relate to the symptoms experienced when icing occurs. Therefore, identifying loss of RPM and engine roughness is crucial in recognizing carburetor icing during flight operations.