# CREW ALERTING SYSTEM (CAS)

### CREW ALERTING SYSTEM (CAS) WINDOW <a href="#crew-alerting-system-cas-window" id="crew-alerting-system-cas-window"></a>

* Four message priority levels:
  * WARNING (red): Indicates an emergency or airplane system condition that requires immediate corrective or compensatory crew action.
  * CAUTION (amber): Indicates an abnormal operational or airplane system conditions that require immediate crew awareness and should require a subsequent corrective or compensatory action.
  * ADVISORY (cyan): Indicates operational or airplane conditions that require crew awareness. Subsequent or future crew action may be required.
  * STATUS (white): Indicates information/ status messages.
    * STATUS LINE
  * Selected by using the CCD. Turning the active CCD scroll knobs scrolls the alert message stack list under the CAS window.
  * Indicates the number and type of messages out of the CAS window, and if they are located above or below.
  * Warning messages are not scrolled out of the window.

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### ROOT EICAS MESSAGES <a href="#root-eicas-messages" id="root-eicas-messages"></a>

* EICAS messages which may generate more messages with them are called Root EICAS messages and they are highlighted by a preceding chevron “>”.

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### EICAS MESSAGE INHIBITION <a href="#eicas-message-inhibition" id="eicas-message-inhibition"></a>

* Some EICAS messages are inhibited on takeoff or approach and landing to prevent it from being a nuisance.