What effect does applying carburetor heat have when ice is present in the carburetor?

Applying carburetor heat when ice is present in the carburetor reduces engine power temporarily because it increases the temperature of the air-fuel mixture entering the engine. Carburetor icing occurs when moisture freezes within the carburetor, which can disrupt the normal flow of fuel and air, leading to a richer mixture and potential engine performance issues.

By applying carburetor heat, the heat causes the ice to melt, allowing for a normal flow of the air-fuel mixture. However, during this process, the introduction of warmer air lowers the overall density of the mixture, leading to a temporary decrease in engine power. The engine may experience a drop in performance until the blockage from the ice is fully cleared and the mixture returns to optimal conditions.

This is a key operational understanding for pilots, as managing carburetor heat effectively is crucial during conditions where icing is likely, ensuring engine performance is maintained while addressing the ice issue.