Question 18 OSV02 - Mate - Offshore Supply Vessels

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 exhibit, in addition to the lights prescribed for a power-driven vessel underway (masthead lights, sidelights, sternlight), **three all-round red lights in a vertical line** where they can best be seen. These lights indicate that the vessel is constrained by the depth or width of the navigable water and must be given extra maneuvering room. **Explanation for why other options are incorrect:** * **B) A vessel moored over a wreck:** A vessel engaged in diving or other similar operations that restrict maneuverability usually displays three all-round lights in a vertical line: green, white, green. A vessel moored (or anchored) over a wreck might simply show anchor lights, unless it is also engaged in operations that restrict its maneuverability (in which case it would be treated as a vessel restricted in her ability to maneuver, which displays red, white, red). There is no specific standard for three all-round red lights for a vessel simply moored over a wreck. * **C) A vessel aground:** Rule 30(e) specifies that a vessel aground displays the anchor lights (forward all-round white light, and stern all-round white light if over 50 meters), and additionally, **two all-round red lights in a vertical line** where they can best be seen. It displays two red lights, not three. * **D) A vessel dredging:** A vessel engaged in dredging operations (which falls under a "vessel restricted in her ability to maneuver") displays three all-round lights in a vertical line: **red, white, red**. Furthermore, if the vessel is restricted in her ability to maneuver, she must also show two all-round red lights in a vertical line on the side where an obstruction exists, and two all-round green lights on the side where another vessel may pass. It does not display three vertical red lights as its primary identifying signal.