Navigational Aids - Pro-Line Boats 33 Express Owner's Manual

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Navigational Aids

Aids to navigation, called ATONS, help you to travel safely on the water. They help you get from one place to
another and are most helpful if you have a nautical chart. Navigational aids are pictured on the following two
pages.
Important
Never tie your vessel to an ATON. It is illegal because it blocks the ATON from the view of other boaters.
Decreased visibility can contribute to a serious accident that may result in property damage, personal injury and
even death. There are two ATON systems. The system used on federal waters is known as the International
Association of Lighthouse Authorities System B, called IALA-B. The Coast Guard maintains this system. The
second system is the Uniform State Water Waterway Marking System known as USWMS. State authorities
maintain this system.
International Association of Lighthouse Authorities System B (IALA-B)
This system uses four types of ATONS. Discussed here are the two most common markers; lateral markers and
safe water markers. Other federal markers include special markers and isolated danger markers.
Lateral Markers
Lateral markers show the sides of navigable channels. They consist of lighted can buoys (nun buoys) and
daymarks. Each has a number and is either red or green. The numbers on green markers are odd and the numbers
on red markers are even. Buoys are red or green floating ATONS. If lighted, they have either red or green lights.
Unlighted green buoys, called cans, look like cylinders. Unlighted red nun buoys have cone shaped tops with
their points cut off. Don't pass too close to a buoy. You may foul the propeller in its chain.
Note:
Buoys are anchored floating objects and may not always be exactly in the same position.
Daymarks are red or green boards with numbers. They are on posts or groups of [pilings tied together and are
called dolphins. Daymarks and their supports are daybeacons. Daybeacons may or may not have lights. If a red
or green daybeacon has a light, it is the same color as the marker, red or green. Red daymarks are triangular and
have even numbers. Green daymarks are square and have odd numbers.
Red, Right, Returning is a basic rule to help you in using lateral markers. When you are returning from seaward,
keep the red markers on the starboard or right side when you pass them. Keep the green markers to the port side
when you pass them.
Returning from seaward is clear if you have been on the ocean. You are returning to port. By agreement, going
upstream on a navigational river is returning from seaward. The outlet ends of the Great Lakes are also the
seaward ends. Traveling from a large body of water to a smaller one is considered returning from seaward.
Safe Water Markers
Safe water markers have vertical red and white stripes and mark the center of navigable channels and fairways.
Safe water markers included both lighted and unlighted buoys and daymarks. If a marker is lighted, the light is
white and flashes the letter "A" in Morse code.
Preferred Channel markers have horizontal red and green bands. If lighted, the color of the light is the same as the
top of the band. They show the preferred channel for you to use at a junction point. Be sure to notice the color of
the top band, and treat is as any other marker you would of the color. If the band is red and you are returning from
seaward, keep the marker to the right.
Most lights on markers flash on and off. Others such as lights on aids with no lateral significance are fixed and
they stay on all night. ATON lights flash in regular patterns. For example, they may flash every three seconds, or
in groups such as two flashes and a pause. There are a number of flashing patterns, which help you identify the
light at night. To identify a light, note its color and pattern or timing of flashes, and compare it to your chart to
find its location.