How does wing anti-ice protection generally operate on a narrowbody?

• A. Electrical heaters are used on the leading edges.
• B. Routing hot bleed air to the leading edges to prevent ice buildup.
• C. Pneumatic de-icing boots are installed on the wing.
• D. Wings are not anti-iced.

Answer: (B)

Wing anti-ice protection on a narrowbody generally operates by routing hot bleed air from the engines to the wing leading edges, heating them to above freezing so ice cannot form or will be melted off. The bleed air flows through ducts in the leading-edge structure and is controlled by valves and sensors to maintain the surface temperature in icing conditions. This method provides rapid, reliable heating over the entire leading edge, which is essential for preserving lift and handling in ice. While electrical heating is used on some designs, the standard approach for common narrowbodies is bleed-air anti-ice. Pneumatic de-icing boots aren’t used on jet wing leading edges, and saying wings aren’t anti-iced misses the safety-critical function in icing conditions.