What conditions necessitate wing and cowl anti-ice during flight?

The correct answer highlights that wing and cowl anti-ice systems should be activated when ice accumulation is indicated, which is crucial for the safe operation of the aircraft. Ice can affect the performance and handling characteristics of the aircraft, leading to potential safety hazards. When ice is annunciated, it serves as a warning to the flight crew that conditions are conducive to ice formation, and activating the anti-ice systems helps prevent ice buildup on critical surfaces.

Maintaining wing and cowl anti-ice is essential, particularly in conditions where the aircraft may be exposed to supercooled liquid water or other icy phenomena. Therefore, in-flight checks that indicate the presence of ice are critical, as they require immediate action to ensure continued safe operations. The operational guidelines regarding anti-ice systems emphasize monitoring for ice accumulation and responding appropriately to enhance the safety of the aircraft.