Question 372 Rules of the Road

The correct answer is B) One prolonged blast. According to the Inland Navigation Rules, Rule 34(a), the required whistle signal for a power-driven vessel leaving a dock or berth is one prolonged blast. This signals to other vessels in the area that the vessel is about to get underway. The other answer choices are incorrect because: A) One short blast is the signal for crossing another vessel's bow, C) Two short blasts is the signal for reversing direction, and D) Two prolonged blasts is the signal for a vessel not under command or restricted in its ability to maneuver.