Question 852 Rules of the Road

The correct answer is A) when making headway. According to the International Regulations for Preventing Collisions at Sea (COLREGS), a power-driven vessel that is "not under command" at night is required to show her sidelights when making headway. This means that even if the vessel is not under command, if it is still moving through the water, it must display its sidelights to indicate its presence and direction of travel to other vessels. The other options are incorrect because: B) a vessel moored to a buoy is considered at anchor, not "not under command"; C) a vessel making no headway would typically be considered at anchor and display anchor lights instead; and D) a vessel at anchor is not required to show sidelights, only anchor lights.