Question 7 OSV02 - Mate - Offshore Supply Vessels

The Correct Answer is C **Why option C is correct:** The scenario describes a situation in an international narrow channel (Rule 9 applies) where a stand-on vessel (the one operating within the channel and restricted by its boundaries) is encountering a crossing vessel, and the operator is in doubt as to the crossing vessel's intentions. Under the International Regulations for Preventing Collisions at Sea (COLREGs), when any vessel operator is in doubt as to the intentions or actions of another vessel, or believes the other vessel is taking insufficient action to avoid a collision, Rule 34(d) (Maneuvering and Warning Signals) permits the use of the danger signal. The danger signal consists of **at least five short and rapid blasts on the whistle**. While Rule 9 mandates certain actions for vessels in a narrow channel (like not impeding others), the general rule regarding doubt and danger (Rule 34(d)) allows for the danger signal to be sounded to alert the other vessel and indicate the confusion or danger. **Why the other options are incorrect:** * **A) You must sound one prolonged and two short blasts:** This signal (one prolonged and two short blasts) is the sound signal required by Rule 35(c) for a vessel **not under command** or a **vessel restricted in her ability to maneuver** (RAM) when making way, or for a sailing vessel. It is not the signal used to express doubt or danger in a maneuvering situation involving a crossing vessel. * **B) You should sound one short blast to indicate that you are holding course and speed:** Under international rules (COLREGs), one short blast indicates "I am altering my course to starboard." Sound signals are generally used to indicate an intended maneuver, not merely to confirm that a vessel is maintaining course and speed (unless there is doubt as to which vessel should maneuver, in which case the danger signal C applies). Using a maneuvering signal (one short blast) to confirm holding course would be misleading under COLREGs Rule 34(a). * **D) You are required to back down:** While maneuvering action may eventually be required under Rule 17 (Action by Stand-on Vessel) if collision cannot be avoided by the other vessel's action alone, the initial requirement when in doubt (which precedes mandatory maneuvering action) is to sound the danger signal (C). Backing down is an extreme maneuver that may be required, but it is not the *required* action solely for expressing doubt about another vessel's intentions.