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Hi John, Most American coastal nautical charts give depths in fathoms, fathoms and feet, or feet, but not in meters. A large number of vessels run aground every year from confusing feet for fathoms. This is easy to do, because most charts have "ALL SOUNDINGS IN FATHOMS" in big letters at the top, then will have an inset harbor chart in feet-only. There would be a real tangible advantage to consistently employing the international standard, meters. The main supplier of American nautical charts is the U.S. Department of Commerce in conjunction with the NOAA. Depths are given in fathoms in big numbers with a small subscript number of feet. For example, 7 with a subscript 2 means 7 fathoms plus 2 feet, or 44 feet. Shallow depths are sometimes given in feet only, e.g, 10 feet rather than 1 fathom 4 feet. Distances are given in nautical miles and yards. In summary, these charges are entirely non-metric. Incidentally, my charts are about 7 years but what I say is probably still true for new charts. I have a Mexico chart that was printed and sold in the U.S. that gives most depths in fathoms, some in fathoms and feet, some close up harbor charts in feet, and one harbor chart in meters! All distances are in nautical miles. Pilot charts are charts of large sections of ocean (north Pacific, south Pacific, etc.) with a chart per month giving lots of information about weather, current, etc. They are produced by the Defense Mapping Agency. The don't give depths, but they do give: Barometric pressure in millibars Wind speed in Beaufort scale Current in knots Distance in nautical miles Visibility in miles Water & air temperature in degrees celsius J. john mercer wrote:
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