If a cabin altitude message is indicated, who assumes Pilot Flying duties?

In the event of a cabin altitude message, the Captain assumes the Pilot Flying duties because this situation typically indicates a potential emergency that requires prompt and decisive action. The Captain, being the Pilot in Command, is responsible for the overall safety of the flight and has the authority to manage the situation effectively.

The Captain has the experience and leadership skills necessary to navigate emergency procedures, communicate with air traffic control, and make critical decisions quickly. While other crew members, such as the First Officer and Flight Engineer, play vital roles in managing the cockpit operations and monitoring systems, it is the Captain who has ultimate responsibility and is trained to handle such emergencies.

In this scenario, the Captain would take control of the aircraft to ensure proper descent to a safer altitude, determine the cause of the cabin altitude issue, and implement any necessary emergency procedures. Other options, such as a First Officer, Flight Engineer, or Senior Flight Attendant, would not typically assume Pilot Flying duties during a critical situation like this, as the hierarchy and structure of command in the cockpit dictate that the Captain remains in control.