What is the primary responsibility of the Executive Officer (XO) on a navy ship?

The primary responsibility of the Executive Officer (XO) on a navy ship is to act as the Aide to the Commanding Officer (CO). This role positions the XO as the second-in-command, directly assisting the CO in managing all aspects of the ship's operations and crew. The XO ensures that the CO's directives are implemented effectively and oversees various departments and personnel to maintain operational readiness.

Although overseeing shipboard logistics, maintaining crew morale, and conducting military drills are also important tasks within the XO's broad range of responsibilities, these are functions that fall under the larger umbrella of supporting the CO. The XO's effectiveness in their role significantly contributes to the overall efficiency and effectiveness of ship operations, making their relationship with the CO crucial for successful mission execution.