What is Navigation and Deck Lights?
Navigation lights are the legally required lighting system that makes your vessel visible to other boats and identifies your size, type, and direction of travel at night or in restricted visibility.
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What it is
Navigation lights are the legally required lighting system that makes your vessel visible to other boats and identifies your size, type, and direction of travel at night or in restricted visibility. The basic system includes: port (red) and starboard (green) sidelights visible 112.5 degrees from dead ahead on each side, a white stern light visible 135 degrees astern. Regulations also require an all-around light or a masthead light depending on how large your vessel is. Depending on the vessel’s size, regulations specify that vessels must display either an all-around light or a masthead light. Always check regulations to confirm which navigation lights are required for your vessel. Deck lights illuminate working areas but must not interfere with night vision or navigation light visibility. Modern systems use LED bulbs that draw minimal power and last thousands of hours.
What it does
Navigation lights communicate your vessel's position, heading and right-of-way status to other vessels through the internationally standardized COLREGS (Collision Regulations) lighting patterns. Red and green sidelights show which way your bow is pointed. Seeing only red means you're looking at their port side, only green means starboard. The stern light shows you're looking at someone's stern. These lights allow other vessels to determine your course and speed at night and judge collision risk. Anchor lights warn approaching vessels you're stationary.
Why it matters
Proper navigation lights are required by maritime law (COLREGS/USCG Navigation Rules). Operating without them can result in fines and liability if a collision occurs. More critically, they're essential collision avoidance tools that tell other vessels where you are and where you're going. A failed starboard light means vessels approaching from your right can't see you're on a collision course. In shipping lanes or crowded anchorages, working navigation lights can be the difference between being seen and being run down by a vessel that never knew you were there.
General Maintenance
Test all navigation lights before every night passage or departure in restricted visibility. Inspect the lights for cracks, dirt, salt accumulation or discoloration that reduces light output. Clean lenses with fresh water and mild soap, more often in salt spray conditions. Check electrical connections for corrosion (navigation light fixtures are highly exposed to weather). Replace incandescent bulbs based on manufacturers recommendations or carry spares as they fail unpredictably. LED systems rarely need bulb replacement but connections can fail. Ensure lights are aimed properly, many masthead lights get knocked out of alignment. Keep spare bulbs and basic tools aboard for emergency repairs. For traditional bulb systems, consider upgrading to LED for reliability and power savings.
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