Figure 5-2. Examples of lateral and non-lateral navigation aids Figure 5-3. Examples of buoys and beacons
• The buoys and beacons on the Mississippi
River are not numbered because placement
is frequently shifted as rapid currents
and shifting sand bars cause relocation
and additions;
• The buoys on the Great Lakes are numbered
from east to west, from the St Lawrence
Seaway to western Lake Superior,
and when westbound you keep red colored
buoys and beacons to starboard.
IDENTIFICATION OF AIDS
The descriptions of all USATONS maintained
in the navigable waters by the USCG,
their colors, shapes, numbers, sounds and
lights are set forth on the nautical charts
and in the USCG “Light List.” In order
to keep the aids in place, prevent damage,
and keep them visible for their intended
safe navigation use by boaters, it is illegal to
moor to an aid to navigation.
The Essential Markers:
On the Water and
On the Charts
The two main types of USATONS are buoys
and beacons. See Figure 5-3. Buoys are aids
that float on top of the water, but are moored
to the bottom of the body of water. Some
have a lights affixed to the top; some do not.
A buoy with a cylindrical shape and a conical
top is referred to as a “nun” buoy. A
Section 5: Navigation Aids 63
Table 5-1. Buoy Characteristics
Shape Cans (C)—cylindrical shape,
or Nuns (N)—conical shape
Color Red, Green, Red/White,
Red/Green, Green/Red,
Red/Black, Yellow
Numbers, or Letters Even or odd numbers, one
or more letters
Sound devices Bells, Gongs, Whistles
Lights Red, Green, White, Yellow
buoy with a cylindrical shape and flat top is
referred to as a “can” buoy. Beacons are aids
that are permanently fixed, most commonly
to the bottom of a body of water. A beacon
that has a light attached is simply referred to
as a “light;” a beacon without a light attached
is called a “daybeacon.” Both buoys and
beacons can provide a variety of navigation
information via shape, color, light and/or
audible signal as summarized in Table 5-1
Buoys appear on charts as diamonds
with small black circles that indicate their
approximate position. The color scheme
within the diamond reflects the color of the
buoy. Lighted buoys on charts are depicted
by a magenta (purplish-red) outline around
their position circles. See Figure 5-5.
Beacons, being permanently fixed in
place, have more reliable positions than
buoys. They may be as large as lighthouses
and as small as daybeacons.
10
11
12
13
14
15
can
nun