Coast Guard Exams
Question 973Rules of the Road90% to pass

BOTH INTERNATIONAL & INLAND While underway in fog, you hear a vessel sound one prolonged blast followed by two short blasts on the whistle. What does this signal indicate?

AI Explanation
The correct answer is A) A vessel towing. According to the International Regulations for Preventing Collisions at Sea (COLREGS), Rule 34(c), a vessel towing another vessel shall sound "one prolonged blast followed by two short blasts" on the whistle or horn while underway and in fog. This signal indicates that the vessel is towing another vessel behind it. The other answer choices are incorrect because they do not match the prescribed sound signal in the COLREGS for a vessel being towed (B), a vessel engaged in pilotage duty (C), or a vessel aground (D).

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