Navigation Lights

Are you sure that your navigation lights are in working order? To take things a step further, are you sure that your navigation lights are positioned correctly? If there have been no modifications to your boat since it was manufactured, your navigation lights are probably still in the right place. If you have added a hard top, a tower, and even some types of canvas, your lights may have been repositioned.

First, lets talk about which of our lights are actually "navigation lights." Our navigation lights include red and green "sidelights," a white "masthead light," and a white "sternlight." On power-driven boats, all four navigation lights are used from sunset to sunrise and during times of restricted visibility. On sailboats, the masthead light is used only when the vessel is motoring.

None of our navigation lights are visible throughout the full 360 degrees of a circle. The masthead light faces forward and shows for 225 degrees of a circle. The sidelights (port - red and starboard - green) each show for 112.5 degrees. Together, they show 225 degrees in the same area as the masthead light. The sternlight is visible for 135 degrees of the circle and faces aft. It cannot be seen simultaneously with a sidelight or a masthead light.

Our navigation lights indicate our orientation to other vessels. Operators of nearby vessels can tell what side of us they are looking at by the red (port) or green (starboard) sidelights. They can tell if we are on a collision course with them when they see both sidelights (red and green) at the same time. Our masthead light shows above the sidelights indicating that we are power-driven and not a sailboat. Our sternlight shows all by itself indicating that we are moving away from them.

In short, our navigation lights show direction in which we are moving and/or our orientation to another vessel. In order for our lights to be effective, they must be facing in the right direction and not obstructed by any part of our boat. On smaller vessels, a 360 degree white light mounted on a pole on the stern serves as both a masthead light (225) and a sternlight (135).

The height of the masthead light above the sidelights is specified to be "at least" 1 meter above the sidelights for vessels up to 40 feet and 2.5 meters for vessels from 40 to 65 feet. If your masthead light not high enough, it may not be sufficiently visible to an oncoming vessel.

Annex I of the Inland and International Navigation Rules includes the specifications for the vertical positioning and spacing of lights. You can refer to it if you are uncertain of whether your navigation lights are properly positioned. The Rules use the metric system of measurement, where one meter is equal to 39.37 inches.

The Navigation Rules are published by the US Coast Guard and are available at an affordable price at most marine stores. All mariners, whether paddling a canoe or at the helm of the largest ship, are responsible to comply with the Navigation Rules. There are no exceptions. If you have the obligation to comply, you need to know what the Rules are. I would keep a copy of the Rules onboard. It can only help!

Until next time, I wish you clear skies, fair winds, and calm seas!