Which term refers to a vessel that must not change course unless necessary?

The term that refers to a vessel that must not change course unless necessary is the stand-on vessel. In navigation rules, a stand-on vessel is one that has the right of way and is required to maintain its course and speed. This designation helps prevent confusion and potential collisions on the water by clearly indicating which vessel should continue on its existing path unless a situation arises that necessitates a change, such as avoiding a collision with another vessel that is required to give way.

Understanding this concept is essential for safe boating practices, as it promotes predictability in vessel movements, allowing operators to anticipate the actions of other vessels on the water. The stand-on vessel is expected to be vigilant and prepared to take evasive action only if the give-way vessel does not take appropriate measures to avoid a collision.