When would a sailboat have their masthead light off?

• A. When sailing and not motoring
• B. When they are anchored
• C. At night
• D. In fog

Answer: (A)

The main idea is how navigation lights indicate what kind of vessel you are and whether you’re using your engine. A masthead light is the white forward light used by power-driven vessels, and it’s also used by sailing vessels only when they are motoring. When a sailboat is moving under sail alone (not using the engine), it isn’t under power, so the masthead light isn’t required and should be off. This helps avoid giving other vessels the impression that you’re a motor vessel ahead of them. Instead, a sailing vessel under way uses sidelights and, if making way, a stern light. If you’re anchored, you’d display an anchor light, not the masthead light. So, the masthead light is off when you’re sailing and not motoring.