When should the wing anti-ice be activated for descent in a CRJ 200?

The wing anti-ice system in a CRJ 200 should be activated when ice is detected or when the aircraft is operating in icing conditions below 230 KIAS. This procedure is critical for ensuring safe flight operations, particularly during descent through atmospheres that could contain supercooled liquid water, which is a primary concern in icing conditions.

By activating the wing anti-ice system under these circumstances, the pilot ensures that ice does not accumulate on the wings, which could adversely affect the aircraft's performance, control, and safety. Ice buildup can alter aerodynamic characteristics, reduce lift, and lead to stall conditions if not managed properly.

In contrast to other scenarios listed, such as activating the system at specific airspeeds or temperatures, effective management of wing icing is primarily dependent on the actual environmental conditions encountered during flight. Therefore, the activation of the wing anti-ice system when ice is either detected or expected in conditions conducive to icing is aligned with best safety practices and operational procedures to maintain aircraft performance.