ASA 105: Skill 6, Aids to Navigation, Lighted marks

 


6.Explain the terms and characteristics used for lighted navigation aids.


Lighted aids to navigation are necessary for night navigation.  The light colors are specific to maritime use and the lights have distinctive characteristics such as frequency of flash.  There are some fixed (not flashing) lighted aids to navigation but not many.  Sandy Hook Light at the entrance to NY Harbor is one.  Others are Hospital Point Light in Salem Harbor and nearby Marblehead Light (fixed green).  Those are the only three seen by the author.


Nobska Light, Massachusetts
This light can be found on chart 1210Tr near Woods Hole.  It is a classic structure with white buildings and red roofs.  The lighthouse itself is a simple tubular building surmounted by the light enclosed in the black ironwork.


Dutch Island Light, Rhode Island
This lighthouse is located on Dutch Island at the western side of Conanicut Island.  Its location can be found on chart 1210Tr.  The structure is unusual in that the building is a square.


Light Characteristics:
Boat Navigation inside front and back flaps shows the essentials.

Eldridge 2022 page 172 shows the characteristics of light flashes and correlates them to chart notation

Lighthouses may show one or more colors (W, R, G) all around or in sectors.

Generally speaking the lights on buoys or beacons are:
W: White is found on white and red safe water marks or on black and red isolated danger marks
G: Green is found on green lighted buoys
R: Red is found on red lighted buoys
Y: Amber/yellow is found on special marks and the buoy is also yellow

In the waters of the USA green marks are kept to starboard when departing a channel.  Red marks are kept to port when departing.  A quick memory aid is "red right returning."  White lights on red and white buoys are kept to port entering or exiting a harbor.  By definition, in coastal waters, you are entering a port when the current is flooding and traveling with you, in your direction.

Note:  In 1980 the US Coast Guard changed from Black buoys to Green buoys.  Chart 1210 Tr was first printed well before 1980 and has not been updated with new buoyage or color identifications.  Buoys painted back are not identified with a color.  Where we might now see G "1" Fl G 4 sec Gong pre 1980 the identity would be "1" Fl G 4 sec Gong.  Lights that are White are not marked with a color on the chart.


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