What is the minimum air temperature at which wing anti-ice must be turned on while in flight?

The minimum air temperature at which wing anti-ice must be turned on while in flight is crucial for ensuring safety and performance in conditions conducive to ice formation. The correct answer indicates that the wing anti-ice system must be activated at temperatures above 10°C when flying through clouds or precipitation that may contain supercooled water.

This procedure is designed to prevent ice accumulation on the wings, which can significantly affect aircraft performance, handling, and safety. Ice formation can lead to reduced lift, increased drag, and potential stall conditions. Therefore, it is essential for pilots to adhere to the temperature thresholds to activate the anti-icing systems in a timely manner.

In contrast, temperatures below 10°C may not require anti-ice activation if the aircraft is not in conditions where ice could form, as lower temperatures might not present the same risk associated with the specific conditions present at 10°C and above.