Question 18 GLI01 - Master-Unlimited Tonnage

The Correct Answer is A. **Explanation for A (A vessel constrained by her draft) being correct:** According to the International Regulations for Preventing Collisions at Sea (COLREGs), Rule 28 (Vessels constrained by their draft), a vessel constrained by her draft may exhibit, in addition to the lights prescribed for a power-driven vessel underway, **three all-round red lights in a vertical line** where they can best be seen. These lights signify that the vessel is restricted in its ability to maneuver due to the depth and width of the navigable water and her own draft. **Explanation for why other options are incorrect:** * **B) A vessel moored over a wreck:** A vessel moored over a wreck does not have a specific requirement to display three all-round red lights in a vertical line. If it is a vessel engaged in diving operations, it would display three all-round lights in a vertical line, but the middle light would be **white**, with the top and bottom lights being red (indicating restricted ability to maneuver), or it would display the 'A' flag (Alpha flag). * **C) A vessel aground:** According to COLREGs Rule 30 (Anchored vessels and vessels aground), a vessel aground displays the lights prescribed for an anchored vessel (forward and aft anchor lights), and additionally, where they can best be seen, **two all-round red lights in a vertical line**. It displays two, not three. * **D) A vessel dredging:** A vessel engaged in dredging (or underwater operations, which are examples of vessels restricted in their ability to maneuver under Rule 27) displays three all-round lights in a vertical line: **red, white, red** (R-W-R). The white light in the middle is crucial. Furthermore, when there is an obstruction, they must also show two all-round red lights on the side of the obstruction and two all-round green lights on the side where another vessel may pass. They do not display three solid red lights in a vertical line.