Question 15

The Correct Answer is A **Explanation for A (Neither vessel is the stand-on vessel.) being correct:** The scenario described involves two vessels crossing in Restricted Visibility (fog) that are **not in sight of one another**. This situation is governed primarily by COLREG Rule 19 (Conduct of vessels in restricted visibility). Rule 19 effectively overrides the crossing rules (Rule 17/15) when vessels detect each other solely by radar or sound signals and are not yet in sight. Rule 19(d) states that a vessel that detects another vessel's presence forward of the beam and judges that a close-quarters situation is developing or risk of collision exists **shall take avoiding action in ample time**. Furthermore, it specifies that this avoiding action **shall not involve an alteration of course to port** for a vessel that is hearing a signal forward of the beam (unless she has determined that a collision will be avoided by that action). Crucially, **Rule 19 does not assign the roles of stand-on or give-way vessel.** Both vessels are obligated to take timely and substantial avoiding action, usually involving reducing speed to bare steerageway (Rule 19(e)) or altering course to starboard, to avoid a close-quarters situation from developing. In restricted visibility, the concept of a "stand-on" vessel does not exist; both vessels are considered "give-way" and must act collaboratively to prevent collision. **Explanation of why other options are incorrect:** * **B) The vessel which hears the other vessel's fog signal first:** The timing of hearing a signal has no bearing on collision avoidance responsibilities. Both vessels must act immediately upon detection (Rule 19(d)). * **C) The vessel which has the other on her own starboard side:** This describes the give-way vessel in a *crossing situation* under Rule 15 (when in sight of one another). Rule 15 does not apply when vessels are solely relying on sound or radar signals in fog (Rule 19 takes precedence). * **D) The vessel which has the other on her own port side:** This describes the stand-on vessel in a *crossing situation* under Rule 15 (when in sight of one another). As explained above, Rule 19 applies, and the stand-on role is eliminated. Both vessels must take action.