Question 30 ONC02 - Second Mate/Third Mate Unlimited Tonnage

The Correct Answer is C **Explanation for Option C (sailing vessel):** The illustration D080RR (often associated with navigation rules) shows two lights visible in an arc of visibility (presumably from the bow): a **red sidelight** and a **green sidelight**. Rule 25 (Sailing Vessels Underway and Vessels Under Oars) dictates the required lights for a sailing vessel: 1. Sidelights (red on port, green on starboard). 2. A stern light (white). If an observer sees *only* the red and green sidelights, it means the observer is viewing the vessel head-on or nearly head-on (within the 112.5-degree arc covered by the sidelights). A vessel showing only sidelights (and no masthead light) is definitively a **sailing vessel** (or a vessel under oars) that is underway, as it is not exhibiting the required masthead light(s) that characterize power-driven vessels, fishing vessels, or pilot vessels. **Explanation of Incorrect Options:** * **A) vessel on pilotage duty:** A vessel engaged in pilotage duty (Pilot Vessel) exhibits two all-round lights: a white light over a red light. Since the illustration shows only red and green sidelights (not stacked white and red all-round lights), this option is incorrect. * **B) law enforcement vessel:** While specialized law enforcement lights exist (often flashing blue or red/blue lights), a standard power-driven law enforcement vessel would display sidelights and a white masthead light (or multiple masthead lights depending on length), which are not shown in the illustration. Therefore, this is incorrect. * **D) vessel engaged in fishing:** A vessel engaged in fishing (Rule 26) displays two all-round lights: a red light over a white light. If it is trawling, it may also show a second white masthead light lower than the stern light. Since the illustration shows only red and green sidelights, and no stacked red and white all-round lights, this option is incorrect.