AIDS TO NAVIGATION 77 



AIDS TO NAVIGATION 



GENEEAL STATEMENT 



Lights, lightships, fog signals, buoys, daybeacons, radiobeacons, and loran (see section 

 on electronic aids to navigation) are the principal aids to navigation shown on the charts. 

 Complete information regarding these aids will be found in the Light List. The correct chart- 

 ing of these aids is illustrated on Figures 1 and 24 in the Appendix, and on Chart No. 1. 



Aids with their characteristics must be so charted that they are identified readily by the 

 chart user and are not obscured by less important information. Care must be taken that the 

 legends which describe the light characteristics fall outside both the magenta disc, used to 

 overprint the dots representing the positions of hghts, and the encircling magenta rings, used 

 to symbolize radiobeacons. 



It is the responsibility of the cartographer and verifier to see that all aids and lettering 

 concerning aids are in their correct positions on compilations and in the areas corrected on 

 Drawings, before being submitted to the Aids Section for checking. 



There is a definite pattern to the placement of aids to navigation marking oiu- harbors and 

 inland waterways known as the Lateral System. The coloring and numbering of Hghts, buoys 

 and daybeacons is determined by their position with respect to the navigable channels pro- 

 ceeding from seaward toward the head of navigation. Even-numbered, red or white hghted 

 buoys and Hghts, mark the right-hand side of the channel entering from seaward. Odd- 

 numbered, green or white lighted buoys and Hghts, mark the left-hand side of the channel 

 entering from seaward. In coloring and numbering of ofi'shore buoys and Hghts along the 

 coasts and along trafiic routes not leading distinctly from seaward, or toward headwaters, the 

 above system applies when proceeding in a southerly direction along the Atlantic Coast, in 

 a northerly and westerly direction along the Gulf Coast and in a northerly direction along the 

 Pacific Coast. The Intracoastal Waterway is similarly marked proceeding from the north 

 Atlantic States to the lower coast of Texas regardless of the compass headings of individual 

 sections. 



When determined by triangulation, the position of all fixed aids must be plotted carefully 

 by their geographic coordinates. When determined by stereo bridging, they shoxild be plotted 

 by their geographic coordinates, directly from Form 567. When not determined by triangiila- 

 tion or stereo bridging, their positions should be transferred carefully to the Drawings from the 

 survey sheets. The symbols for buoys, daybeacons, and Hghts, together with their accompany- 

 ing lettering, should be so placed as to keep channels clear. 



