NS100

Fundamentals ofNaval Science

Visual Navigation Aids

Types of Aids to Navigation

Buoys - Floating aids to navigation.

Lights - Fixed aids to navigation with distinctive light characteristics that make them identifiable at night.

Major Lights

On the Range

Range Lights

To the right of the range.

Visual Range

On the RangeThe location of the rear range

relative to the front range will indicate your relationship to the range line.

Beacons

Fixed aids to navigation used in U.S. waters– Each has daymark ( or ) to

denote right or left-side channel boundary– Beacons may be unlighted (daybeacons) or

lighted

Types of Aids to Navigation

Radio Beacon - used with a direction finding receiver, will yield an LOP.

RACON BuoysRACON Buoys to identify aids to navigation, both seaborne (e.g. buoys) and land-to identify aids to navigation, both seaborne (e.g. buoys) and land-

based (e.g. lighthouses) based (e.g. lighthouses) to identify landfall or positions on inconspicuous coastlines to identify landfall or positions on inconspicuous coastlines to indicate navigable spans under bridges to indicate navigable spans under bridges to identify offshore oil platforms and similar structuresto identify offshore oil platforms and similar structures

General Buoyage Classification Lateral - Used to indicate on which side the buoy should be passed and are used to mark channels.

Car

dina

l Sys

tem

C

ardi

nal S

yste

m

of B

uoya

geof

Buo

yage

Buoy Description and Purpose Can Buoy

13

Buoy Description and Purpose Nun Buoy

12

Sound Buoys Bell Gong Whistle Horn

Lighted Buoys

Combination Buoys Any buoy in which a light and a sound

signal are combined

Examples include:– Lighted bell– Lighted gong– Lighted whistle– Lighted horn

Buoy Description and Purpose Buoys are painted different colors according to their purpose. Lateral Aids - Either red or green or the combination of the two.

Cardinal Aids - Painted black and yellow.

Lateral Buoyseither red

or green, or a

combination of the two.

Numbered from seaward,

meaning the numbers increase

as you approach land.

Buoy Description and Purpose Safe Water Marks - presence of a channel. Fitted with a red ball topmark or a white light flashing MORSE ALPHA. Special Marks - Painted yellow.Isolated Danger Marks - Painted black and red.

Special Buoys Used to mark:

– Prohibited areas– Limits of fish traps– Cable crossings– Anchorages– NOAA weather buoys

Color is yellow– Usually unlighted– NOAA weather buoys are lighted and typically use a

flashing 4 or 6 second yellow light

13

Buoyage Systems There are two buoyage systems in the world today: IALA “A” and IALA “B”.

International Association of Lighthouse Authorities (IALA)

Buoyage Systems IALA “B” memory aids:

Red Right Returning

Even Red Nuns have Odd Green Cans

Light Attributes Color Phase Characteristics Period

Color Common colors:

WhiteRedGreen

Illustration Symbol and meaning

F. = Fixed

F.Fl. = Fixed and flashing

F.Gp.Fl. = Fixed and group flashing

Fl. = Flashing

Gp. Fl. = Group flashing

Gp. Fl. (1+2) = Composite group flashing

Mo. (A) = Morse code

Qk. Fl. = Quick flashing

I.Qk.Fl. = Interrupted quick flashing

E.Int. = Equal Interval (Isophase)

Occ. =Occulting

Gp.Occ. = Group occultingGp.Occ. (2+3) = Composite group occulting

Lights and Lighted BuoysLateral and Channel Buoys - red or green with flashing phase characteristics.U.S. Safe Water Marks - Show a white light with Morse “Alpha” ( ) with a period of about eight seconds.Fixed Lights and Lighthouses - variety of phase characteristics, lights, and colored sectors to distinguish from the background lights of the shore.

Ch

ann

el

Bu

oys

Safe Water BuoysSafe Water Buoys

Preferred Channel BuoysPreferred Channel Buoys

16

16

1616

16

16

1616

16

20

2020

20

14

14

14

14

14

14

14

14

14 14

12

12

12

12

10

10

1010

10

10

8

8

8

8

8

4

4

4

4

4

4

6

6 6

6

2

2

21

Mast

Piles

PepeReefUncov.

1 m

HobbsRks

PepeIsland

10

Dredged 10 ft 1996R2

G1

R12Fl R 2.5s

G C 3

R N 4

Kentmore marina

Pepe PtFl 6s 54ft 7M

R14Fl R 5s

G13Fl G 2.5s

16

14

12

10Mast

Aids To Navigation

Using Buoys and Lights in Piloting

Buoys should never be used to fix your

position!Lights and Lighthouses - fixed andprovide for good visual fixing both during the day and at night.