The nacelle anti-ice system uses engine bleed air to provide engine cowl inlet ice protection. it can be operated in flight or on the ground.
The wing anti-ice system provides bleed air to each wing. It's inhibited in flight when leading edge flaps are extended and on the ground.
In flight when WAI is in auto the system operation is automatic. It can also be oprerated manually when the WAI is ON. No anti-ice system on the tail section because it's not necessary.
P.S. ask those recruiters in HKG why they rejected my application.
A2B