In-flight anti-ice with ICE annunciation, which surfaces are anti-iced?

• A. Wing only
• B. Tail surfaces
• C. Wing and Cowls
• D. All surfaces

Answer: (C)

Anti-ice systems are focused on surfaces where ice most disrupts aerodynamics and engine airflow. When ICE annunciation is active, the heating is applied to the wing leading edge and the engine cowls (nacelles) to prevent ice from forming there. These areas are critical for maintaining lift and smooth engine airflow, so they’re protected first. Tail surfaces aren’t typically included in this in-flight anti-ice circuit, either due to lower icing risk for those surfaces or to save weight and power. So the surfaces that are anti-iced in this scenario are the wing and the cowls.