What must a vessel do if it cannot accurately determine the windward vessel?

In situations where a vessel is unable to accurately determine which vessel is windward, it has a responsibility to keep out of the way of the other vessel. This guideline is reflective of the maritime principle of ensuring safety and preventing collisions, especially in scenarios where visibility or other factors may complicate navigation. By yielding to the other vessel, it upholds the overarching regulation of safe vessel operation, which places the priority on avoiding collisions.

The expectation to keep out of the way also emphasizes the need for vigilance and caution during maneuvers in unpredictable circumstances. The decision to yield contributes significantly to maritime safety, ensuring that if there is any uncertainty regarding right of way, the action taken minimizes the risk of an accidental collision.

In contrast, the other options present less prudent courses of action. Not sailing may not be practical or necessary, as the vessel could be navigating safely under certain conditions. Proceeding as normal without awareness of nearby vessels could lead to dangerous situations, and signaling the other vessel, while potentially helpful, does not replace the obligation to take precautions by giving way. Therefore, keeping out of the way is the most responsible and safe action when the windward vessel cannot be determined.