Which anti-ice systems protect the A321 and when are they activated?

• A. Wing anti-ice uses hot bleed air; windshield anti-ice uses electrical heat; activated in icing conditions or when icing is detected
• B. Wing anti-ice uses hot bleed air; windshield anti-ice uses electrical heat
• C. Wing anti-ice uses electrical heat; windshield anti-ice uses hot bleed air
• D. Wing anti-ice uses hot bleed air; windshield anti-ice uses electrical heat; activated in icing conditions or when icing is detected

Answer: (A)

On an A321, protecting surfaces from ice relies on two systems working in tandem: wing anti-ice and windshield anti-ice. The wing anti-ice system uses hot bleed air from the engines to heat the leading edges of the wings, preventing ice from forming there. The windshield anti-ice system uses electrical heating elements embedded in the windshield to keep it clear of ice and fog.

Activation happens when icing conditions are present or when ice is detected by the aircraft’s sensors, so these systems can come on automatically or be commanded by the crew as needed. This combination—hot bleed air for the wings and electrical heating for the windshield, with activation tied to icing conditions or ice detection—best matches how the A321’s anti-ice protection is designed.