What does the 1st Substitute flag indicate?

The 1st Substitute flag indicates that a flag officer is ashore. This is a signal used in naval operations to communicate the status of senior officers. When the 1st Substitute is displayed, it conveys that the commanding officer or a higher-ranking officer, who may usually be aboard the vessel, is not present but is instead on land.

This flag is essential for maintaining proper command and communication protocols within naval operations. It informs other vessels and personnel that while a senior officer is not currently on board to oversee operations, there is a chain of command still in place and functioning. The significance of this flag helps prevent confusion regarding the status of command and ensures that all personnel are aware of the leadership structure at that moment.