What is flat, not powered by a battery, sits in a corner or sleeps under a bunk cushion most of the time, and is often treated like a disowned black sheep of the family?
Master seaman Sid Stapleton says they are “…the most valuable and essential tools we have on board our ships.” Navigation guru Nigel Calder calls them “…the start and end points of navigation.” And Caribbean cruise captain Donald Street says: “It’s rarely possible to have too many…”
Now, you may disagree with some of these master sailors about priorities, but in my opinion, your nautical chart ranks right up there with the ship’s anchor and sail as the most important tools on board.
One spark and you can lose your navigation black box. That’s all it takes to fry electronics. So let’s take a minute to go back to the simple basics you should use every time you’re sailing along the coast or offshore.
This is not the textbook version, but the realistic version of yachting made simple. Which means, no chart table, heeling, spraying the bow, and feeling a little green, all at the same time. It all starts long before you leave the first docking line.
These seven super simple steps will work on any size boat anywhere in the world. Here’s how to complete 90% of your chart sailing for safer boating wherever you choose to sail:
1. Plan your navigation route
Use the largest scale navigation chart for the sailing area of the sailboat. Larger scales show more detail for entering ports, anchorages, passing near hazards, and using navigation aids. Look under the title of the table for the ratio. The smaller the second number, the larger the scale.
For example, in US waters, the best charts for coastal navigation have a scale of 1:80,000. This means that one inch on the chart is equal to 80,000 inches on the earth’s surface. Once you get on the coast and into ports, you’ll want an even larger scale, like 1:40,000 for much better detail.
Use the “what if” factor when choosing the right scale chart to use. What if the weather turns bad, or you have an injury on board and need to enter a port at night, or need to find an anchorage for the night? Your navigation chart must offer the best detail for the safest navigation day or night, in any maritime climate.
2. Draw your tracking lines (TR)
Trace your navigation courses, called “track lines,” on your chart with a pencil. Use the outer ring of the compass rose to plot in the true direction. Many people like to use the magnetic ring (second ring) of the compass, but not all charts have a magnetic ring. Those used offshore only show the true direction. Convert the true heading to a magnetic heading with the variance shown in the center of the wind rose.
Add the western variance and subtract the eastern variance. For example, if you plotted a true heading of 038 true and the center of the wind rose showed a variance of 3E, subtract the variance from the true heading to find the magnetic heading (035M).
Some charts do not have compass roses at all. Instead, they show regular magenta (purple) dashed diagonal lines that span real estate on the chart. These are called isogonic lines. Look along the line to find the variance. Use the same rules as above to convert your true heading to a magnetic heading.
3. Label your magnetic steering course
Write the magnetic course at the top of each of your tracking lines. Label the course with three digits and a capital M (for magnetic). For example, for a magnetic course of 35 degrees magnetic, you would write 035M at the top of the line. For a magnetic course of 8 degrees magnetic, you would write 008M at the top of the track line.
To make your labels clearer, draw a small arrow breaking between the magnetic label, with the arrowhead pointing in the direction of travel. For example -035M-> Prayed -008M->
4. Look for hazards and score
Take the time to very carefully scan to the right, left, and ahead of your track line. Look for any hazards such as dangerous wrecks, shoals (shallow spots), rip current notations, or other areas that could put your boat in danger.
Mark them with colored pencils to make them stand out day or night, in any type of weather. Do not use red to score as it will become invisible if you use red lights to maintain night vision. Instead, stick with blues, greens, magenta (nautical purple), or black.
5. Plug your tracking lines
Purchase removable Scotch tape or any similar brand that can be removed and written on. Tape the penciled tracks and add a strip above and below (to label or trace positions). That way you can reuse the chart over and over again and the tape provides a protective barrier against the ravages of pencil lead, erasers and the needle tips of your navigational dividers.
6. Make it black and bold
Use a fine-tipped black marker to trace the penciled navigation tracks across the top of the tape. Write your course labels at the top of each track line with the felt-tip marker.
7. Tie it to a board
Make your chart ready to use in the booth. Fold the card to reveal the navigation area. Tie it to a legal size clipboard or use an artist sketch board with rubber bands. In rainy weather, slide the board into a large ziplock-style plastic bag.
Use these seven super-easy navigation tips to make cockpit chart navigation more fun, safer, and easier than ever. He will become a more confident boater, always prepared to bring his ship home safely!