Question 13

The Correct Answer is A. **Explanation for Option A (Correct):** Option A states, "Slow to minimum to maintain course and navigate with caution." This action is required by Rule 19(e)(i) of the International Regulations for Preventing Collisions at Sea (COLREGs), which applies to both International and Inland waters (as the Inland Rules generally mirror COLREGs Rule 19). Rule 19 governs the conduct of vessels in restricted visibility. Specifically, Rule 19(e) mandates that if a vessel detects the presence of another vessel forward of the beam by radar (or, by hearing its fog signal, as this indicates a vessel is nearby and poses a risk of collision): 1. The vessel must take avoiding action in ample time. 2. If circumstances permit, the vessel must "reduce her speed to a minimum necessary to keep her on course." 3. She must navigate with extreme caution until the danger of collision is over. Hearing a fog signal ahead indicates the presence of a vessel whose position is unknown but dangerous, thus requiring the vessel to slow down to the minimum steerageway speed and proceed cautiously. **Explanation of Why Other Options Are Incorrect:** * **B) Slow to moderate speed and navigate with caution:** A "moderate" speed is subjective and generally still too fast for conditions where an unseen vessel is known to be ahead in heavy fog. Rule 19 explicitly requires speed to be reduced to the *minimum* necessary to maintain course, not merely a moderate speed. * **C) Stop engines and navigate with caution:** While stopping engines might seem cautious, it only applies if the vessel has reached a point where collision is imminent and stopping is the only option, or if the vessel is a non-self-propelled vessel. A self-propelled vessel must maintain steerageway to maneuver and take avoiding action, which requires maintaining a *minimum* speed. Stopping the engines entirely would render the vessel unable to control its course effectively, potentially increasing the risk of collision if immediate action is required. * **D) Maintain speed and sound five short and rapid blasts:** Maintaining speed in restricted visibility when a vessel is detected ahead violates the foundational principle of Rule 19. Furthermore, sounding five short and rapid blasts (the danger signal) is the correct signal when a vessel doubts the intentions of another vessel *in sight*, or doubts whether sufficient action is being taken to avoid collision. This signal is not the required action solely upon hearing a fog signal ahead in restricted visibility.