Light List, ranges, and light characteristics

Bowditch Ch. 5 §501

Short Range Aids to Navigation Aids to navigation include lights, buoys, beacons, and electronic aids. The US lateral system follows IALA-B: red on the right returning from sea, even numbers on red, odd on green.

Bowditch Ch. 5 §502

Short Range Aids to Navigation The light list is the authoritative reference for the characteristics, range, height, and structure of all USCG-maintained aids. Always update the light list against the weekly Local Notice to Mariners.

Bowditch Ch. 5 §503

Short Range Aids to Navigation A light is described by its characteristic, colour, period, height, and nominal range — for example "Fl R 4s" is a red light flashing once every four seconds. Common characteristics are fixed (F), flashing (Fl), occulting (Oc), isophase (Iso), and quick (Q). The Light List gives the authoritative character, range, height, and structure of every aid, and is the reference for identifying a light by its characteristics at night.

Bowditch Pub. 9 Ch. 4 §438

Aids to Navigation Aids to navigation are shown by symbols listed in Sections P through S of Chart No. 1. Abbreviations and additional descriptive text supplement these symbols. In order to make the symbols conspicuous, the chart shows them in size greatly exaggerated relative to the scale of the chart. “Position approximate” circles are used on floating aids to indicate that they have no exact position because they move around their moorings. For most floating aids, the position circle in the symbol marks the approximate location of the anchor or sinker. The actual aid may be displaced from this location by the scope of its mooring. The type and number of aids to navigation shown on a chart and the amount of information given in their legends varies with the scale of the chart. Smaller s…

Bowditch Pub. 9 Ch. 6 §607

Light Lists The United States publishes two different light lists. The U.S. Coast Guard publishes the Light List for lights in U.S. territorial waters; NGA publishes the List of Lights for lights in foreign waters. Light lists furnish detailed information about navigation lights and other navigation aids, supplementing the charts, Coast Pilots, and Sailing Directions. Consult the chart for the location and light characteristics of all navigation aids; consult the light lists to determine their detailed description. The Notice to Mariners corrects both lists. Corrections which have accumulated since the print date are included in the Notice to Mariners as a Summary of Corrections. All of these summary corrections, and any corrections published subsequently, should be noted in the “Record o…

Bowditch Pub. 9 Ch. 7 §713

Range Lights A range consists of two or more beacons so positioned with respect to each other that when seen aligned they mark a line of definite bearing, the range line commonly delineating the centerline of a navigation channel. These aids to navigation are typically affixed with duel-colored vertically striped dayboards for alignment during daylight hours and if lighted, exhibit lighted signals during periods of darkness. Some ranges Figure 712. Typical Major Light. SHORT RANGE AIDS TO NAVIGATION 115 exhibit a light signal 24-hours a day, which may or may not be equipped with dayboards. The rear range is designed and constructed so that it is higher than the front range to enable mariners to align the ranges; the rear range light will always be above the front light for the height of …