Sooner or later, your ability to read a chart, whether it’s on paper or on an electronic display, will directly affect the safety of your boat and your crew. That’s particularly true at night or during times of restricted visibility. Here’s a good, clear refresher story from Skipper Tips about how to read the markings for night lights that will help keep you on a safe course:
Imagine that your GPS has been unreliable for the past several hours. You approach the coast as the sun dips below the western horizon. An overcast promises a black night without the benefit of starlight. You strain your eyes to pick up the lights of the harbor entrance. What three factors will make this challenge safer and easier?
Sail anywhere in the world and you will encounter lights and shapes that guide, warn or alert the mariner. How are lights segregated from unlighted aids to navigation? How are they labeled to tell the sailor whether they are fixed or floating?
Light structures or lighted buoys show a magenta colored disk or teardrop next to or over the position, designated by a black dot, star or small open circle. Often, buoys show a small open circle instead of a black dot. This represents the swing-circle of the buoy.
Buoys are anchored to the bottom much like a vessel, with a chain and sinker (the “ground tackle” of the buoy). Buoys may or may not maintain their position. Storms or storm surge can drag a buoy from its assigned position.
How are Floating Aids Lettered, Lighted and Labeled? (Right Side of Illustration)
– Letters
Slanted letters are used to identify objects that float, shift, bob, sway, swing, or have the potential to shift position from wind, current, wave or swell. Look at the three chart symbols on the right side of the illustration. All of the buoy description characters (letter or numbers) are slanted.
– Lights
Notice that each of these floating aids has a magenta colored disk or teardrop over the black dot or small open circle. The first symbol shows the position as a black dot. The next two symbols shows the position as a small open circle. If a magenta disc is used, it will always be superimposed atop the position circle. Read more:
https://www.skippertips.com/public/Sail-Safer-This-Season-with-These-Landfall-Light-Secrets.cfm
