Question 41

The Correct Answer is B. **Why option B ("One short, one prolonged, and one short whistle blast") is correct:** Rule 35(d) of the COLREGs (International Regulations for Preventing Collisions at Sea, which covers both International and Inland waters for this context) specifies the emergency or supplementary signal to be used by an anchored vessel in restricted visibility when danger of collision exists from an approaching vessel. The rule states: "A vessel at anchor may in addition to the signal in subparagraph (g) of this Rule sound **one short, one prolonged and one short blast** in quick succession to give warning of her position and of the possibility of collision to an approaching vessel." This signal is used to alert the approaching vessel that the anchored vessel is present and immobile, and that action needs to be taken by the moving vessel to avoid collision. **Why the other options are incorrect:** * **A) One prolonged, one short, and one prolonged whistle blast:** This sequence is not a prescribed signal in the COLREGs for this specific situation or any standard maneuvering or warning purpose. * **C) One prolonged followed by two short whistle blasts:** This is the prescribed maneuvering signal given by a power-driven vessel that is **not in sight of another vessel** when approaching a bend or an area of the channel where other vessels may be obscured (Rule 34(e)). It is not the signal used by an anchored vessel in fog to warn of a collision danger. * **D) No signal other than your fog signal may be used:** This is incorrect because Rule 35(d) explicitly permits (and encourages, given the danger) the use of the supplementary warning signal (one short, one prolonged, one short) in addition to the required fog signal (Rule 35(g), which is a rapid ringing of the bell for 5 seconds).