When your commanding officer is on leave, which flag should be flown?

The correct flag to be flown when the commanding officer is on leave is the third substitute. The third substitute flag indicates that the commanding officer is not present, allowing for a clear signal to others that the usual chain of command is temporarily altered. This practice is rooted in naval tradition, ensuring that the status of leadership on a vessel or station is transparent to all personnel and visitors, maintaining order and clarity in command structure.

The other substitute flags have different meanings. The first substitute is used when the commanding officer is absent but not on leave, often indicating a designated officer is temporarily in charge. The second substitute signals the absence of the executive officer. The fourth substitute is not a standard flag used to denote the absence of key personnel and thus would not be appropriate in this context. Each substitute flag serves a specific purpose, so understanding the correct flag to raise in each scenario is essential for proper naval protocol.