Question 7 ONC06 - Master LT 100 GRT

The Correct Answer is C **Explanation for C (Correct):** 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) of the **COLREGs (International Regulations for Preventing Collisions at Sea)**, which applies internationally. Although the scenario primarily involves Rule 9 (Narrow Channels), the action taken when in doubt is a warning signal. Rule 34(d) states: "When vessels are in sight of one another, any vessel may sound at least five short and rapid blasts on the whistle or horn when she is in doubt as to whether sufficient action is being taken by the approaching vessel to avoid collision." Since the crossing vessel's intentions are doubtful, sounding the danger signal (five short blasts) is the appropriate action to warn the other vessel and indicate your uncertainty regarding the situation. **Explanation of Incorrect Options:** **A) You must sound one prolonged and two short blasts:** This signal is defined by Rule 34(e) and indicates that a vessel intends to overtake another vessel on its **port side**. This signal is irrelevant in a crossing situation where the vessel is simply in doubt about the intentions of another vessel. **B) You should sound one short blast to indicate that you are holding course and speed:** According to Rule 34(a)(i), one short blast indicates "I am altering my course to starboard." Sounding one short blast when holding course and speed is incorrect and misleading. Furthermore, if you are in doubt, holding course and speed without signaling that doubt is unsafe; the primary action is to signal the doubt. **D) You are required to back down:** While taking evasive action, including reducing speed or backing down, might be necessary under Rule 8 (Action to Avoid Collision) or Rule 17 (Action by Stand-on Vessel) if a risk of collision develops, you are not *required* to back down as the immediate first response to being in doubt. The immediate requirement when in doubt is to signal that doubt (five short blasts) before taking drastic physical action.