What do the code flags NE2 indicate when exhibited by a warship?

The code flags NE2, when exhibited by a warship, specifically indicate that submarines are operating in the area. This signaling is important for ensuring that other vessels are aware of potential submarine activities, which can include operations that are not visible on the surface. The display of these flags serves as a warning to nearby vessels to exercise caution, maintain proper distance, and adhere to appropriate navigation protocols to avoid any interference with submarine operations.

Understanding this signal is crucial for maritime safety and the protection of submarine missions, as submarines may be submerged and not visible to other vessels. Hence, this coded communication plays a critical role in enhancing situational awareness in shared maritime space.