Question 7 GLI06 - Master or Mate of LT 100 GRT

The Correct Answer is C **Explanation for C (Correct Option):** Option C states, "You may sound at least five short and rapid blasts on the whistle." This action is governed by **Rule 34 (Maneuvering and Warning Signals)**, which applies universally, but is especially relevant when applying the rules regarding narrow channels (Rule 9). Rule 34(d) of the **International Regulations for Preventing Collisions at Sea (COLREGs)** states: "When vessels in sight of one another, a vessel shall, if from any cause she is in doubt whether sufficient action is being taken by the other vessel to avert collision, sound at least five short and rapid blasts on the whistle." Since the scenario specifies you are "in doubt as to his intentions," sounding the doubt/danger signal (at least five short blasts) is the appropriate action under the COLREGs to alert the other vessel to your apprehension regarding the developing situation. **Explanation of Incorrect Options:** * **A) You must sound one prolonged and two short blasts:** This signal (one prolonged, two short) is the **fog signal for a power-driven vessel underway but stopped and making no way** (Rule 35(b)). It is inappropriate for a vessel operating in a narrow channel during clear visibility and expressing doubt about another vessel's intentions. * **B) You should sound one short blast to indicate that you are holding course and speed:** Under COLREGs (International Rules), whistle signals are signals of **action**, not intention or reassurance. A single short blast indicates "I am altering my course to starboard." Sounding this signal when you are merely holding course and speed (as required by Rule 9) would be a misleading signal of action, especially since you are doubtful of the other vessel's movements. * **D) You are required to back down:** While you must take avoiding action if necessary (Rule 17), there is no specific rule requiring you to immediately "back down" (reverse engines) merely because you are in doubt about another vessel's intentions. Furthermore, Rule 9 emphasizes that a vessel navigating a narrow channel must not impede the passage of a vessel that can only be safely navigated within that channel (which you are), suggesting that backing down and stopping might endanger your own safe passage unnecessarily at this stage. The immediate requirement when in doubt is to signal that doubt (five short blasts), as per Rule 34(d).