Question 18 GLI04 - Mate of LT 500-1600 GRT

The Correct Answer is A **Explanation for A (A vessel constrained by her draft):** Rule 28(b) of the International Regulations for Preventing Collisions at Sea (COLREGs) specifies the lights for a vessel constrained by her draft. Such a vessel shall, in addition to the lights prescribed for a power-driven vessel of the same length, exhibit **three all-round red lights in a vertical line** where they can best be seen. These three vertical red lights signify the restriction in her ability to maneuver due to her draft. **Explanation for B (A vessel moored over a wreck):** A vessel moored or operating over a submarine cable or pipeline or engaged in certain diving operations generally displays lights indicating she is restricted in her ability to maneuver (Rule 27(b)), which involves red-white-red all-round lights (or three shapes: ball-diamond-ball). A vessel simply moored over a wreck does not have a specific set of lights defined by COLREGs as three vertical red lights. A wreck itself is marked by a specific lateral or cardinal mark, or a buoy displaying a flashing blue or yellow light (not covered by COLREGs vessel lighting). **Explanation for C (A vessel aground):** A vessel aground displays the lights prescribed for a vessel at anchor (an all-round white light or lights), and in addition, she shall exhibit, where they can best be seen, **two all-round red lights in a vertical line** (Rule 30(d)). Since the question specifies three red lights, this option is incorrect. **Explanation for D (A vessel dredging):** Dredging vessels are classified as vessels restricted in their ability to maneuver (Rule 27(b)). When underway, they display the red-white-red all-round lights (ball-diamond-ball shapes during the day). Specifically, when the vessel is restricted in its ability to maneuver due to dredging or underwater operations, it also displays two all-round red lights in a vertical line to indicate the obstructed side, and two all-round green lights in a vertical line to indicate the side on which another vessel may pass (Rule 27(d)). They do not display three vertical red lights solely to identify themselves.