Question 7 GLI05 - Master or Mate of LT 200 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(d)** (Maneuvering and Warning Signals), which applies universally to the International Regulations for Preventing Collisions at Sea (COLREGs). Although the scenario specifically mentions Rule 9 (Narrow Channels), the general rule for addressing doubt or danger is found in Rule 34(d). Rule 34(d) states that if vessels are in sight of one another, and for any reason either vessel is in doubt as to the intention or actions of the other, or is concerned that insufficient action is being taken, the vessel in doubt **shall** indicate such doubt immediately by sounding at least five short and rapid blasts on the whistle (the danger signal). Since the question states you are "in doubt as to his intentions," sounding the danger signal is the appropriate action. **Explanation of Incorrect Options:** **A) You must sound one prolonged and two short blasts:** This signal (one prolonged, two short blasts) is the restricted visibility signal for a vessel not under command, a vessel restricted in her ability to maneuver, a sailing vessel, a fishing vessel, or a towing vessel (Rule 35(c)). It is also used by a vessel being overtaken in a narrow channel to signal their desire to pass on the starboard side (Rule 9(e)(i)). It is not the signal for indicating doubt about another vessel's intentions in clear visibility. **B) You should sound one short blast to indicate that you are holding course and speed:** A single short blast indicates an action: "I am altering my course to starboard" (Rule 34(a)(i)). It is a maneuvering signal, not a signal for indicating doubt. Furthermore, a stand-on vessel holds course and speed, but they do not use a sound signal simply to announce that they are holding course and speed; sound signals communicate *intentions* or *doubt*. **D) You are required to back down:** While taking avoiding action (including backing down) is required under Rule 17 (Action by the Stand-on Vessel) if a close-quarters situation cannot be avoided solely by the action of the give-way vessel, Rule 9 specifically addresses the requirement for the crossing vessel to avoid impeding the passage of the vessel constrained to the narrow channel. More immediately, when a vessel is in doubt, the first requirement is to sound the danger signal (Rule 34(d)). Maneuvering (like backing down) is an action taken once a collision risk is confirmed, not the required immediate response solely to the condition of *doubt*.