What should a vessel do if it is uncertain about another vessel's actions?

When a vessel is uncertain about the actions of another vessel, the prudent course of action is to be ready to take action to avoid a collision. This principle is rooted in the fundamental tenet of navigational safety, which emphasizes that mariners must always prioritize avoiding collisions whenever there is any doubt about the intentions of another vessel.

By being prepared to take evasive action, a vessel can react promptly to an unexpected maneuver by another vessel, ensuring safety for all parties involved. This may involve adjusting course or speed, or taking other measures to create safe distances. Maintaining a cautious approach allows mariners to make informed decisions even in ambiguous situations, thereby mitigating risks on the water.

In contrast, adjusting speed to match the other vessel can lead to confusion rather than clarification, and assuming a vessel has the right of way without knowing the other's intentions could lead to dangerous situations. Sounding the horn continuously may not convey useful information and can escalate tension or confusion without effectively communicating intentions. Thus, readiness to take action is the most appropriate response when uncertainty exists.