What does a white CAS message mean?

A white CAS (Crew Alerting System) message indicates that maintenance attention is required and that the aircraft cannot depart with that specific annunciation present. This is a critical communication tool used in aviation to ensure that flight crews are alerted to conditions that could potentially affect aircraft safety and operational readiness.

When a white CAS message appears, it signifies that there is a non-normal situation that requires resolution before continuing with the flight. This can include issues like a system malfunction or a component that is not functioning within its established parameters, necessitating maintenance intervention.

The other options do not accurately reflect the significance of a white CAS message. For instance, evasive action or flight path adjustments pertain more to immediate operational responses and are not implied by a white message. Meanwhile, operation within normal parameters generally would not trigger any CAS message, as the system communicates when deviations occur.