Question 26 GLI03 - Master-LT 500-1600 GRT

The Correct Answer is D **Explanation for Option D (Correct):** Option D is a direct application of the special lighting provisions for Great Lakes vessels defined in Rule 23(f) of the Inland Rules (which incorporates specific exemptions and substitutions relevant to the Great Lakes). Specifically, for power-driven vessels of less than 50 meters in length operating solely on the Great Lakes, the rule states that an all-round white light may be carried in lieu of the second masthead light and the stern light. This substitution simplifies the required lighting configuration for smaller vessels operating in this region. **Explanation for Incorrect Options:** **A) Great Lakes vessels are exempted from the requirement to show yellow towing lights.** This is incorrect. The requirement to show yellow towing lights (a specialized stern light carried above the white stern light) applies to vessels when engaged in towing, including those on the Great Lakes, and is defined in Rule 24. There is no general exemption from this requirement for Great Lakes vessels. **B) Sidelights for vessels over 50 meters are required to have only a two-mile range of visibility.** This is incorrect. For power-driven vessels 50 meters or more in length, the minimum range of visibility required for the sidelights (red and green) is mandated to be **3 miles**, not 2 miles (Rule 22, Table 84.15). The 2-mile requirement applies only to sidelights on vessels between 20 meters and 50 meters. **C) The showing of a forward masthead light is optional for vessels under 150 meters.** This is incorrect. The forward masthead light is a mandatory requirement for all power-driven vessels underway (Rule 23(a)(i)), regardless of length, unless specifically exempted (e.g., small vessels under 12 meters may substitute an all-round white light). Furthermore, vessels 50 meters or more must show **two** masthead lights (forward and after). The forward masthead light is a core navigational light and is never optional for Great Lakes vessels of this size range.