Boating and Sailing.pdf - Moja ladja

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Part 3: Getting from Point A to Point B: Marine Navigation
Harbor charts sometimes go as large as 1 inch = 35,000 inches; an inch on the chart
equals only about a half-mile on the water. This will show every little creek and sandbar,
so it’s the one most useful for inshore boaters and anglers.
Measuring Chart Distances
There are mileage scales printed along the bottom of most charts, making it possible to
easily measure distance with a set of dividers. Dividers don’t actually divide anything, such
as a calculator. A divider is a two-legged device with sharp points on the legs that is
designed to let you transfer a measurement from the chart to the mileage scale along the
edges or at the bottom of the chart.
Digital Navigation
With a computer and electronic charting software, you can plan your voyages in advance.
There are numerous companies now offering CDs with not only nautical charts but also
thousands of coordinates for prime fishing, diving, and gunk-holing. With the computerized
systems, you can lay out your course for a day or a week, determine the cruising
times required, estimate how much fuel you’ll need to make the trip, and even add typed
notes on things to watch for, and then print out hard copies to take with you on the boat.
On larger boats with enclosed cabins, you may want to simply take along a portable computer
and run the chart software as you need it. Just remember, computers are not happy
long if you keep them around salt air and away from air conditioning.
The ultimate chart is one that’s coupled with a GPS system and shows you where your
boat is in relation to the chart on a real-time basis. These are available as add-ons for
portable computers and also built in to charting GPS systems, which we’ll cover in the
electronics chapter.
The Least You Need to Know
◆ Charts are watergoing road maps.
◆ Charts contain depth information based on color and numbers as well as shape of
land masses and shoals.
◆ Markers shown on charts help to locate your position afloat.
◆ Choosing the right scale for your type of boating makes a chart much more useful.