Question 7 ONC03 - Master LT 500-1600 GRT

The Correct Answer is C **Why option C ("You may sound at least five short and rapid blasts on the whistle") is correct:** This scenario involves a vessel operating in a narrow channel (Rule 9) encountering a crossing situation, and the operator is in doubt as to the intentions of the other vessel. International Rule 34(d) (Maneuvering and Warning Signals) addresses situations of doubt or ambiguity. Rule 34(d) states: "When vessels in sight of one another are approaching each other and from any cause either vessel is in doubt whether sufficient action is being taken by the other to avert collision, the vessel in doubt **shall** indicate such doubt by giving at least five short and rapid blasts on the whistle." Since the operator is in doubt about the intentions of the crossing vessel, sounding the danger signal (at least five short and rapid blasts) is the required action to alert the other vessel and express doubt, regardless of the vessel's status in the narrow channel. **Why the other options are incorrect:** * **A) You must sound one prolonged and two short blasts:** This signal is defined by International Rule 34(e) as the sound signal required when a vessel is leaving a berth or dock. It is not the signal used to express doubt in a maneuvering situation. * **B) You should sound one short blast to indicate that you are holding course and speed:** Under International Rules, a sound signal is required only when maneuvering (e.g., altering course to starboard or port) or when expressing doubt. There is no signal (like one short blast) solely designated to indicate holding course and speed. Furthermore, using a maneuvering signal (one short blast means "I am altering my course to starboard") when you are only expressing doubt would be confusing and misleading. * **D) You are required to back down:** While taking evasive action (including reducing speed or stopping) is necessary if collision is imminent, there is no requirement to immediately "back down" as the primary response to being in doubt about another vessel's intentions. The immediate and required action when in doubt is to sound the danger signal (C).