Question 44 ONC06 - Master LT 100 GRT

The Correct Answer is D **Explanation for Option D (Correct Answer):** According to both the International Regulations for Preventing Collisions at Sea (COLREGs) and the U.S. Inland Rules, a power-driven vessel using her whistle must sound specific signals to indicate maneuvering intentions. The signal consisting of **three short blasts** (short blast: about one second duration) signifies that the vessel is **operating astern propulsion** (backing engines). This signal is used when the vessel is slowing down significantly or reversing course. **Explanation for Incorrect Options:** * **A) Vessel "A" intends to hold course and speed:** There is no specific maneuvering signal designated by three short blasts for holding course and speed. A vessel that is simply maintaining course and speed generally sounds no signal, or, if operating in sight of another vessel and initiating a passing maneuver, might use signals indicating the side of passage (one or two short blasts) or, under Inland Rules, a danger signal if disagreeing. * **B) Vessel "A" is sounding a signal of doubt:** The signal of doubt (or danger signal) is **five or more short blasts**. Three short blasts has a definite meaning (backing engines). * **C) Vessel "A" proposes to cross ahead of the other vessel:** A vessel proposing a maneuver typically uses one or two short blasts (indicating passing on the starboard or port side, respectively, depending on the rules of the waterway and situation), but three short blasts specifically indicates astern propulsion, not an intention to cross ahead.