Navigation
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Contents |
Basics
The basics of good navigation?
- Dividers have dual functions. They are used to measure distances on a chart and they are used for determining latitude and longitude. Two varieties can be found. The less expensive version requires two hands to set. The traditional one-handed divider is more expensive.
- Plotters are used to determine bearings and courses on the chart. Most people are used to seeing parallel rules, but common plotters are Portland Plotters, Douglas protractors, course arm plotters.
- The hand bearing compass is an essential piece of equipment. Nautical hand bearing compasses are used to take bearings accurate to 1°. They cost more than a simple hand-held compass, but are worth the expenditure. They can also be used at night.
- Binoculars can be used to identify aids to navigation at a distance. Nautical binoculars are usually “7X50”. They magnify to a power of 7 times. Any binoculars more powerful than this are unstable on a moving boat. They have a 50-millimetre objective, or front, lens to admit sufficient light for use at night. Some binoculars have a built-in compass.
- Knowing the depth of water in which you may find yourself is crucial. Traditionally this was determined through the use of a weighted lead line which was “swung.” Knots along the line indicated the depths in fathoms. Electronic depth sounders use a technology similar to sonar. Depth sounders can be set to that they account for the depth of the keel. Ensure that you are aware of any offset programmed into a depth sounder.
- Knotmeters measure the speed of the vessel through the water. The speed and direction of any current must be taken into account to determine the true speed across the bottom.
- A watch or clock is another essential navigational tool.
- Time, speed, distance calculations and other mathematical tasks are simplified using a digital calculator.
- A time , speed, distance computer, a misnomer, is a circular slide rule that can be used in place of a calculator. No batteries are needed.
Paper Charts
How to work with paper charts?
Electronic Charts
- C-Map
The Logbook
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References
Publications, etc.
Forum Discussions
Links to discussion threads on the CruiserLog Forum
External Links
- American Practical Navigator (Bowditch). Probably the definitive navigation text book, pdf download
- British Admiralty: The Mariners Handbook, pdf download
- British Admiralty: Digital chart catalogue
Personal Notes
Personal experiences?
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