Question 47 AB01 - Able Seafarer

The Correct Answer is D **Explanation for Option D (A 16-meter sailing vessel):** Option D is correct based on the Convention on the International Regulations for Preventing Collisions at Sea (COLREGs), specifically Rule 25 (Sailing vessels underway and vessels under oars) and its associated Annex I, Section 5 (Positioning and Technical Details of Lights and Shapes). * **COLREGs Rule 25(b):** "In a sailing vessel of less than 20 meters in length the lights prescribed in Rule 25(a) may be combined in one lantern carried at or near the top of the mast where it can best be seen." * Rule 25(a) prescribes sidelights and a stern light. * A 16-meter sailing vessel is less than 20 meters, thus meeting the length requirement for combining these three lights into a single tri-color masthead lantern. This arrangement is permissible under both International and Inland Rules (which generally mirror COLREGs for this specific provision). **Explanation of Incorrect Options:** **A) A 25-meter power-driven vessel:** This is incorrect. Power-driven vessels of this size (25m) must display separate and distinct lights: sidelights, a stern light, and two masthead lights (fore and aft). They are not permitted under COLREGs Rule 23 to combine these lights, regardless of the vessel's length. **B) Any non-self-propelled vessel:** This is incorrect. While many non-self-propelled vessels (like barges being pushed or towed) may use simplified lighting arrangements (e.g., only sidelights), they are governed by specific rules (Rule 24, Rule 30) regarding vessels constrained by draft or towing/pushing. The ability to combine sidelights and a stern light into a single fixture is explicitly reserved for small sailing vessels (under 20m) and certain small power-driven vessels (under 7m) that cannot exceed 7 knots, not for all non-self-propelled vessels generally. **C) A 28-meter sailing vessel:** This is incorrect. The maximum length permitted for a sailing vessel to utilize the combined tri-color lantern is less than 20 meters. A 28-meter sailing vessel must display the standard separate sidelights (on the hull) and a separate stern light.