Question 24 OSV02 - Mate - Offshore Supply Vessels

The Correct Answer is A **Why Option A is Correct:** This scenario is specifically addressed in the International Regulations for Preventing Collisions at Sea (COLREGs), Annex I, Section 5, which covers the specifications for the location and technical details of lights and shapes. For WIG (Wing-In-Ground) crafts, Rule 23 (Power-driven vessels underway) applies regarding their required lights, but due to their unique construction and operational characteristics, they often cannot physically meet the specific spacing and height requirements set forth in Annex I. Annex I, Section 5(c) states the governing principle for such specialized vessels: "The masthead light or lights must be so placed as to be clear of and above all other lights and obstructions except as specified in sub-paragraph (ii). ... (ii) **The vertical spacing of masthead lights of a wing-in-ground (WIG) craft shall be at the maximum possible height consistent with the design characteristics of the craft and shall be as specified by the competent authority of the State whose flag the craft is entitled to fly.**" Therefore, the WIG craft is required to comply with the rules as closely as possible, and the specific limitations and resulting compliance standard are determined and approved by the vessel's flag state (her government). **Why Other Options Are Incorrect:** * **B) An all-round light should be substituted for the after-masthead light and the stern light.** This suggestion introduces a substitution that is not authorized for a standard power-driven vessel (Rule 23) and does not address the specific issue of masthead light spacing required for WIG crafts. While some vessels use all-round lights, WIGs must generally display the prescribed masthead lights, albeit at the maximum possible vertical spacing. * **C) The WIG must carry only the lights that comply with the rules; the others may be omitted.** This is incorrect and dangerous. Omitting required navigation lights (such as a second masthead light or a stern light) violates the fundamental requirements of COLREGs (Rule 23) and would severely compromise the vessel's visibility and identity to other vessels. The rules require maximum possible compliance, not omission. * **D) The WIG must be altered to permit full compliance with the rules.** While full compliance is always preferred, the premise of the question is that the vessel *cannot* comply due to fundamental design limitations (inherent to being a WIG craft). COLREGs recognize that altering the design of such specialized vessels to meet every technical specification may be impossible, which is why the flexibility provided in Annex I, Section 5(c)(ii) exists.