Question 25 TV01 - Towing Vessels - Oceans or Near Coastal

The Correct Answer is B **Explanation for Option B (Correct Answer):** The placement requirements for navigation lights, including the masthead light, are detailed in the International Regulations for Preventing Collisions at Sea (COLREGS) and corresponding national rules (like the U.S. Inland Rules). For **power-driven vessels less than 12 meters in length**, Rule 23(c)(i) provides an exception allowing the masthead light to be placed *off* the fore-and-aft centerline. This exception is granted if centerline placement is impractical, provided that the masthead light (or all-round white light, which is often used instead of a masthead light on very small vessels) is offset but still meets visibility and arc requirements, and is located where its presence does not cause "undue practical difficulty." **Explanation of Incorrect Options:** **A) which has separate sidelights carried on the outboard extremes of the vessel's breadth:** This describes a specific arrangement for sidelights (Rule 23(a)(ii)), primarily used for power-driven vessels 20 meters or more in length to maximize separation. While this dictates sidelight placement, it does not grant an exception for offsetting the **masthead light** from the fore-and-aft centerline. **C) engaged in fishing:** A vessel engaged in fishing (Rule 26) must display specific identification lights (e.g., green over white, or all-round white light for gear extending out more than 150 meters). These lights are generally required to be displayed where they can best be seen, but the rule governing the *masthead light* placement (Rule 23) does not grant a blanket exception for centerline placement simply because the vessel is fishing, unless the vessel is also less than 12 meters in length. **D) less than 20 meters in length:** While vessels less than 20 meters have several light arrangement alternatives (e.g., combining the masthead and stern light into one all-round white light, or combining the sidelights in a single lantern), the specific regulatory exception allowing the **masthead light to be located off the centerline** is limited to vessels **less than 12 meters** in length (Rule 23(c)(i)), not the entire category of vessels less than 20 meters.