Question 15 RVR05 - Master of LT 100 GRT

The Correct Answer is A **Explanation for A (A seaplane):** Rule 31 of the International Regulations for Preventing Collisions at Sea (COLREGs) governs seaplanes. It states that: "Where a seaplane on the water is unable to comply with the provisions of these Rules concerning lights and shapes, she shall in complying with the provisions of Rules 4 to 19 inclusive, have regard to the fact that she is such a vessel." Rule 18 (Responsibilities between Vessels) establishes the hierarchy of right-of-way. While a seaplane is generally treated as a power-driven vessel when maneuvering on the water, Rule 18(a)(iii) specifically states that a power-driven vessel (which includes a seaplane when underway) **shall keep out of the way of** a vessel engaged in fishing, a sailing vessel, and a vessel not under command. Since a seaplane is essentially treated as a power-driven vessel when on the water and maneuvering, it must keep clear of all the other listed options (B, C, and D). Therefore, a power-driven vessel should not impede the navigation of a seaplane only when the seaplane is restricted by draft or unable to maneuver due to external circumstances, but in the standard hierarchy of Rule 18, the seaplane (as a power-driven vessel) should not impede another power-driven vessel, but it *must* keep out of the way of vessels B, C, and D. The question asks which vessel's navigation a power-driven vessel should **not impede**. When two power-driven vessels (like a seaplane and a standard power-driven vessel) meet, the rules of passing (such as head-on or crossing situations) apply, meaning neither has absolute right of way, but neither is required to automatically keep out of the way of the other in the Rule 18 hierarchy. In contrast, the power-driven vessel *must* keep clear of B, C, and D. **Why the other options are incorrect (must be kept clear of by a power-driven vessel):** * **B) A sailing vessel:** This is incorrect. According to COLREGs Rule 18(a)(ii), a power-driven vessel **shall keep out of the way of** a sailing vessel. Therefore, the power-driven vessel must impede its own navigation to accommodate the sailing vessel. * **C) A vessel not under command:** This is incorrect. According to COLREGs Rule 18(a)(i), a power-driven vessel **shall keep out of the way of** a vessel not under command. * **D) A vessel engaged in fishing:** This is incorrect. According to COLREGs Rule 18(a)(ii), a power-driven vessel **shall keep out of the way of** a vessel engaged in fishing.