Question 3 RVR01 - Master of Unlimited Tonnage

The Correct Answer is B **Explanation of Option B (Correct):** Option B states that a course change alone may be the most effective action provided that **it is a large course change**. This principle is directly derived from the International Regulations for Preventing Collisions at Sea (COLREGs), Rule 8 (Action to avoid collision). Specifically, Rule 8(b) mandates that any alteration of course and/or speed to avoid collision shall, if the circumstances of the case admit, be **large enough to be readily apparent to another vessel observing visually or by radar**. A succession of small alterations of course should be avoided. The key is to make the avoiding action clear, definitive, and unambiguous. A large course change meets this requirement, maximizing the chance that the other vessel will detect the action and recognize the intent, thereby helping to ensure a safe passing distance. **Explanation of Other Options (Incorrect):** * **A) the course change is to starboard:** While Rule 19 (Conduct of vessels in restricted visibility) and Rule 14 (Head-on situation) generally favor a turn to starboard, the effectiveness of an action taken to avoid collision (Rule 8) is determined by its magnitude and clarity, not solely its direction. A large turn to port might be required in certain crossing or overtaking situations, or if it is the only way to avoid immediate danger. Therefore, direction alone does not guarantee effectiveness. * **C) it is done in a succession of small course changes:** This is explicitly contradicted by Rule 8(b), which advises against a succession of small alterations of course. Small, successive changes make the action ambiguous and difficult for the other vessel to detect and interpret, potentially delaying or confusing the collision avoidance process. * **D) it is NOT done too early:** While Rule 8(d) states that action taken must be "timely," the issue of "too early" is generally not the primary determinant of effectiveness. The key to effectiveness for a course change alone is its magnitude (large enough to be apparent). Action should be taken early enough to be effective, but the magnitude of the change is the factor that makes it most effective as a singular action. Taking a large, early action is ideal, but the regulation focuses on the size of the alteration to ensure visibility.