Sunday 13 April 2008

Selecting Paper Charts

With all the digital technology and nautical software available to we mariners it is tempting not to have paper charts on board. However, for the reasons listed below you would not set sail on long passages without them. The new print on demand waterproof charts are a great advance........read on.

Paper charts are key navigational tools on nearly every vessel, even with advances in technology that make digital electronic charts affordable and convenient. They serve as a primary means to plan and record routes, an accurate backup to electronic charts and a reliable source of interesting information about the waters where you enjoy boating.

New Print-on-demand technology now makes paper charts as up-to-date as possible, with the latest Notice to Mariners, corrections, and NGA & NOAA safety updates available daily.

Who creates them?Charts of U.S. waters are created by the National Oceanographic & Atmospheric Agency (NOAA), which produces more than 1000 charts covering the U.S. coastlines and major waterways, plus coast pilots, tide and current tables. The National Geospatial-Intelligence Agency (NGA), produces charts of international waters, lists of lights, sailing directions, sight reduction tables, pilot charts and other publications to complement charts.

The Canadian Hydrographic Service (CHS) is the source for charts of Canadian waters.
Chart SelectionSince U.S. charts are in the public domain and are not subject to copyright law, many private companies produce them in paper and digital form. We carry an extensive selection of these charts.

Consider the following selection criteria when choosing a chart:
Scale: Common chart scales range from large (e.g. 1:10,000) to small (e.g. 1:2,000,000). Remember, a large-scale chart covers a small area, and a small-scale covers a large area.
Kinds of charts: World and international sailing charts are used when voyaging across oceans or a long stretch of coastline.

For example, Chart 530 covers the area from the Aleutian Islands to Mexico and Hawaii at a scale of 1:4,860,700 with very little detail. General charts are considered coastal cruising charts with a scale between 1: 150,000 and 1: 600,000. They show much more detail than international sailing charts but still not enough for navigating close to shore or sailing into port.

Coast charts provide excellent detail for coastal navigation and all but the smallest harbors at a scale from 1: 40,000 to 1:80,000. Harbor charts show a relatively small area in great detail and should be used when making port. Often they have insets that show critical areas at a scale of 1:10,000.

Enhanced Content: Many private companies have taken the core data from government charts and enhanced it to provide additional value. Waterproof charts are printed on synthetic paper for use on deck or in small boats. Fish/dive charts show GPS positions for reefs, fishing grounds and wrecks.

Being Chart SavvyLatest editions: Many charts change frequently, so look for the edition date, which is printed at the bottom. A list of the most current editions of NOAA charts is available at http://nauticalcharts.noaa.gov/mcd/dole.htm

Chart Catalogs: NOAA, NGA and CHS publish free chart catalogs, which we have available in our warehouses. These show the coverage areas for each chart and are essential for planning a trip.
Chart Number 1: If you are unfamiliar with reading charts, ask for a copy of Chart No. 1 which explains the symbols and abbreviations used on nautical charts.

Depths: Water depth may be given in feet, fathoms or meters, and is generally measured at low water. This means that it is a conservative measure of whether you’ll run aground; generally the tide level will be higher and you’ll have some breathing room.

The Compass Rose: There are usually several compass roses printed on a chart, oriented to the North. Direction is measured as a straight line from the center of the circle to a degree number on the compass rose. The true direction is printed around the outside, the magnetic direction around the inside of the compass rose. The variation, which is the difference between true and magnetic North, is printed in the middle of the rose, along with the annual change.

Charts Available From West Marine:
Print-on-Demand charts from NOAA by Oceangrafix
Standard charts from NOAA, NGA, Canadian Hydrographic, plus privately produced charts
Print-On-Demand by OceanGraffixPrint-On-Demand charts provide the latest updated information, and have become the standard for timely accuracy.

New Print-On-Demand editions are available five to eight weeks before traditional lithographic charts, using digital technology, and they don’t print until you order them. They are updated daily with the most recent local and regional Notices To Mariners corrections, unlike traditional charts that are months (or even years) out of date. Because of this guaranteed up-to-date accuracy, we believe Print-On-Demand charts add an important level of safety for mariners, since coastlines gradually change, sandbars move, storms rearrange submerged hazards and the government alters its regional information. These charts are approved by NOAA, meet USCG carriage requirements, and are SOLAS compliant.

Full size Print-On–Demand charts are single-sided, either 36” or 42” wide, and between 36" and 48" in length. Distinctive graphics and vibrant colors make them easier to read than traditional paper charts, and they include added safety information, boating tips and emergency procedures.

Our Print-On-Demand charts are printed on heavy-duty water-resistant paper and are shipped directly to you by three-day FedEx ground service. Print-On-Demand charts are also available in-store at our Ft. Lauderdale and San Diego locations. They cost the same as traditional charts and the difference in quality is substantial.

Reproduced courtesy of Westmarine at www.westmarine.com

You can read much more about navigation and charts in my ebook 'Voyage of the Little Ship 'Tere Moana' downloadable from my website www.sailboat2adventure.com

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