Question 364 Rules of the Road

The correct answer is A) One prolonged blast. According to the Navigation Rules and Regulations, when a vessel is departing a pier or other mooring and is moving out into the main channel, it should sound one prolonged blast on the whistle or horn. This signal indicates that the vessel is getting underway and alerts other vessels in the area to its movement. The other answer choices are incorrect because they do not match the appropriate whistle signal for this situation. Three long blasts, five or more short rapid blasts, and one prolonged and two short blasts have different meanings and are used for different situations, such as warning signals, distress signals, or mooring operations.