PART 6 AIDS TO NAVIGATION
Navigation aids are nautical road signs that can be used to help you determine your position, follow a safe course and to warn of dangers. Aids to navigation may be divided into two broad categories:
Here’s a buoy on a chart plot- ter. For more details, place the cursor over it and press ENTER.
Buoys are floating marks anchored (moored) in a fixed position. Buoy positions depicted on a nautical chart are approximate within the swing movement allowed by the scope of their mooring cable. Be aware they can sometimes drag from their position as a result of storms, ice or impact with a ship.
A box pops up with more information.
Beacons are fixed to the sea bottom or located on shore, making them a reliable and precise aid for navigating. Beacons include daybeacons with a daymark, beacons with a light (lights), lighthouses, and ranges.Buoys and beacons with lights can be identified by their color (red, green, white, or yellow) and rhythm (pattern of their flashes). There are a variety of rhythms displayed by various lights. Most unlit marks have reflective tape that will be picked up by your searchlight. All marks are identi- fied on charts. Anything floating (typically a buoy) is shown at an angle from the vertical, while fixed objects are straight up and down. NOTE: This is not necessarily the case with plotter charts.
There are four different navigation marking systems used in U.S. waters: 1 The U.S. Marking System is used on all navigable waters in the U.S., with the ex- ception of the Mississippi River and its tributaries and the Intracoastal Waterway.
2 The Information and Regulatory Markers used on navigable state waters and non- navigable internal state waters.
3 The Intracoastal Waterway System used on the Intracoastal Waterway from New Jersey through Texas.
4 The Western River System used on the Mississippi River and its tributaries.
The Conventional Direction for lateral marks is a clock- wise rotation around the U.S.
U.S. Marking System Lateral Marks. A system of lateral marks is used to indicate on which side a mark should be passed when returning from seaward. In U.S. waters, red marks are kept on your right (starboard) side and green ones on your left (port) side. Remember this orientation by the “3 Rs” of “RED, RIGHT, RETURNING (from seaward).” When an approach from seaward cannot be determined, the Conventional Direc- tion is used, which is a clockwise rotation around the U.S. land mass and northerly and westerly in the Great Lakes, except for southerly in Lake Michigan.
Caution
It is illegal to tie onto an aid to navigation or be in a position that prevents other vessels from seeing it.
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Preferred Channel Marks. When channels divide, one will be “preferred” for deeper draft vessels or as part of a continuing waterway. It may or may not be the one you want, but at the division you will find a preferred Light: same color as up- permost band (if lighted) and is a group flashing light, e.g., Gp Fl (2+1) 6s (2 flashes and 1 flash every 6 seconds) channel buoy. This may be passed on either side but will exhibit a preferred side based on the color of the uppermost band. If the main chan- nel is to your left, when returning from seaward, the top band will be red indicating the buoy is to be passed on your right (starboard) side. If the top band is green that indicates the preferred channel is to the right and the buoy is to be passed on your left (port) side. Color: red and green horizontal bands Shape: cans, squares, nuns, and triangles Character: letter (s) Light: same color as uppermost band (if lighted) and is a group flashing light, e.g., Gp Fl (2+1) 6s (2 flashes and 1 flash every 6 seconds).
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