If you are a stand-on vessel, when should you take action?

As a stand-on vessel, it is your responsibility to maintain your course and speed unless it becomes evident that the give-way vessel is not taking the appropriate action to avoid a collision. The primary principle of the "stand-on" situation is that you should not take evasive maneuvers while the other vessel has the duty to yield. However, if you determine that the give-way vessel is not moving or is in a position where a collision may occur, it becomes crucial to take action to ensure safety.

This approach allows the stand-on vessel to maintain predictability, which is essential for the give-way vessel to maneuver safely. If a stand-on vessel were to take unilateral action without a clear reason—such as when the give-way vessel is properly yielding—it could lead to confusion and potentially dangerous situations. Therefore, taking action is warranted only in the event that the give-way vessel is failing to fulfill its responsibility to avoid a collision.