Question 30 ONC03 - Master LT 500-1600 GRT

The Correct Answer is C **Explanation for why option C ("sailing vessel") is correct:** Illustration D080RR shows a combination of lights: 1. A **red sidelight** and a **green sidelight** (indicating a vessel underway). 2. A **red over green** all-around light configuration displayed vertically. According to the COLREGs (International Regulations for Preventing Collisions at Sea) Rule 25, a power-driven vessel underway must show masthead lights, sidelights, and a stern light. A sailing vessel underway is only required to show sidelights and a stern light, but Rule 25(c)(i) permits a sailing vessel to exhibit the optional vertical configuration of **red over green** all-around lights at or near the top of the mast. This "Red over Green, Sailing Machine" mnemonic indicates a sailing vessel. Since the illustration displays the necessary running lights (sidelights) and the optional "red over green" display, the vessel is identified as a **sailing vessel** underway. **Explanation for why the other options are incorrect:** * **A) vessel on pilotage duty:** A vessel engaged in pilotage duty displays two all-around lights in a vertical line: **white over red** ("White over Red, Pilot Ahead"). * **B) law enforcement vessel:** While law enforcement vessels often display flashing blue lights, their primary identification lights (if they are exhibiting status lights) do not universally utilize the red over green configuration. This configuration is specifically reserved for sailing vessels (optionally) or, in other contexts (like trawling), for fishing. * **D) vessel engaged in fishing:** A vessel engaged in fishing that is **trawling** displays **green over white** ("Trawling light, Green over White"). A vessel engaged in fishing other than trawling displays **red over white** ("Fishing boat, Red over White"). The illustrated light combination (red over green) does not match the mandatory lights for any type of fishing vessel.