Window OF NAVIGATION TERMS
There are many reasons for you to learn and understand the fundamentals of kayak navigation and implement them into your trip plan. The art and science of navigation is an ancient one, utilizing simple tools that are readily available.
Using a chart and compass will allow you to find your way through unfamiliar territory and complicated waterways with lots of islands, coves and peninsulas. Such areas possess extraordinary kayaking views and adventures to the paddler familiar with navigation basics.
You will also be able to determine your position and direction of travel in fog, night, and low visibility due to heavy rain. At any time you will be able to know where you are and communicate that to any one who may to need to know. You could use GPS devices to achieve these goals, but electronics are not necessarily able to hold up in wet environments, particularly salty ones. Batteries often fail or are forgotten. The use of a good chart or map is still necessary to clearly understand the "lay of the land." Any sensible outdoors person will carry a compass; why not know how to use it? GPS has great applications, and I am not discounting their use, but this article does not contain information on how to use them.
You will need, as pictured above:
A chart is a map for nautical use. A chart will detail information that is of interest to mariners, such as water depth, rocks, wrecks, shoreline terrain; and aids to navigation, such as buoys or lights.
A chart utilizes a "compass rose" consisting of three concentric rings showing all 360 degrees, like a round protractor; the outer one oriented for true north, the middle one for magnetic north.
The innermost ring shows all the compass points, north, east, south and west, etc, just like a compass, without the abbreviations. As kayakers we will want to use the middle ring for numerical magnetic "bearings."
Distances can be measured on a chart using the "scale" (in nautical miles) or the "latitude scale" along the right and left borders of the chart, NOT the longitude, top and bottom. A nautical mile (abbreviated as NM or nm) is equal to 1.15 statute miles or 1.85 kilometers. There is not that much difference but it can add up fast and give you problems if you are not aware of the difference.
Chart #1 is the "chart" that is the legend or key to all the symbols, abbreviations and features that are shown as drawings on any marine chart. By getting this "Chart #1" you will be able to better understand the codes marked next to buoys and lights, and the difference between a sand beach and a rocky beach. Charts, and Chart #1, can be obtained at many marine supply stores. Also check our Resources & Links for this article.
TOPO MAPS: You can now order water-proof topo maps on-line. See "MyTopo"
A "topographical map" will detail information that is of interest to landlubbers. Topographical maps will show the contours of the land in great detail, roads, trails, springs and "non navigable" (to ships and large power boats) waters that may not be detailed on charts.
This type of map may be the only kind available for inland lakes and rivers. A topo map will also show the declination (or difference) of true north and magnetic north, depicted as an angle. There is however no compass rose.
A topo map has a scale like any other map, and it is in statute miles, just like the ones we use while driving. To make measurements of distance on any map or chart, use a ruler, your fingers or the measuring edge of a compass. Make a measurement of your route and compare to the scale or vise versa. While at home, not in the field, you could use dividers or a compass (the kind you draw circles with) as a measuring instrument. Topo maps have a legend in a separate publication called "Guide to topographic map symbols." You can use this to better understand the symbols, and abbreviation and read your topo maps.
MAGNETIC NORTH VS TRUE NORTH
True north is the direction to the geographical top of the earth, aka the North Pole. Magnetic north is an area of strong magnetic attraction that is near the North Pole, in Canada. The magnetic north pole is just like an end of a magnet, with the Earth being a very large magnet. Because the true North Pole and the magnetic north pole are close, but in two different places on the globe there is almost always a difference between true north and magnetic north compass bearings. This can be as much as twenty degrees or more in some places. In Northeast America this is usually about fifteen degrees. In the mid west and southern states the numbers are small, zero to ten degrees. On the west coast variation (at sea, charts) or declination (on land, topo maps) is about fifteen to twenty degrees. Check the area you are in carefully for the declination.
A compass will always point to magnetic north. As a kayaker magnetic north will be the way you will record compass bearings. Compasses come in a variety of styles. A pocket or hand held compass is the most common. This variety should have a strait edge and a rotating dial called an azimuth ring. A pocket compass is very handy to have in your PFD pocket.
A deck-mounted compass is the best for a kayaker to have. It will mount on your kayaks bow deck in a position that you can easily see. It will tell you what direction your kayak is pointed in by displaying the compass degrees to the rider in the cockpit.
Other compasses will have features that allow you to sight a more accurate reading. They can be very useful, but as kayakers we will tend to round off our readings (to the nearest five degree mark) to utilize easy to see and use numbers.
Any compass can be strongly affected by metal nearby. Your compass needle will not be accurate if there is any iron containing metal in close proximity. When using a hand held compass check to make sure your pocketknife is not too close. When loading your kayak make sure that the cargo nearest to your deck-mounted compass does not contain a cast iron fry pan. When in doubt about an item that may affect your compass, slowly bring it near the compass and see if it causes the needle to move. This will tell you how far away to stow that item and if it indeed will affect the compass.
PARALLEL RULERS AND PREPARING YOUR CHART
(Chart in this section courtesy of Bradshaws & Assoc.)
Parallel rulers are a tool that is used to plot a course on a chart
using the chart's compass rose. The parallel rules consists of two
rulers that are connected by hinges. They are used to draw two perfectly
parallel lines far apart from each other, on your chart. You will
likely use the parallel rules, at home, while planing your trip,
because their use on the deck of a kayak is impractical. The goal
is to draw lines on your map representing the legs of your journey
and to transfer those lines to the compass rose in order to obtain
compass courses that can be notated on your map.
Place your parallel rules on that line and draw the line right on your map using the strait edge of the ruler. Without moving the ruler from your line, hold one rule firmly in place, while you slide the other rule over to the compass rose. Hold the rule, that you have just moved, down firmly and then slide the other rule to catch up with the first. You will have to slide one rule at a time to walk them over to the compass rose. Once you have reached the compass rose align the strait edge through the center of the rose and draw a line right trough it.
(Use a pencil and you can erase later if you wish, but this will make it easy for now.) Always hold one rule down firmly while you move the other rule so that the line on your compass rose is perfectly parallel to the line representing your intended route. This may take some practice to walk the rules across the map.
Follow the line from the center of the rose in that direction to the middle ring marked "Magnetic." Find the number closest to the line. It is best to round up or down to the nearest five degrees. Your deck-mounted compass will likely show only the spots every five degrees. Write that number next to the line on the map that represents your route. You may want to put the letter M next to that number to indicate that it is a magnetic compass bearing as opposed to a true north bearing. Find other straight legs of your journey and do the same for each leg. This will help you navigate across the large open areas of water, where you will be most susceptible to low visibility or an inability to determine islands, and peninsulas from shoreline in the background.
Be careful about determining the correct bearing from the compass rose. It is easy to mistakenly record the complete opposite bearing, such as 180 degrees instead of 0 degrees, which would be the difference between south and north, or 270 degrees in stead of 90 degrees, which would be the difference between west and east.
It is, however, practical to know what the opposite direction is, called a "back bearing." There are circumstances where you may want to make an about face and turn back the way you came to escape bad weather, find a slow kayaker, or retrieve a forgotten item on the last beach. If you are good with numbers this will be a snap, but if you are unfamiliar with navigation you may want to indicate the back bearing next to your line of travel on your map.
You will encounter portions of your route that will not be strait. These will generally be along coastlines, or around islands. It is impractical to determine a multitude of compass bearings to describe a curved line. You will use coastlines and landmarks along these areas to help you navigate, if the weather is clear enough to see. If you are paddling in poor visibility you will want to use other aids. The sound of the waves can help you determine where shore and shallows are. Buoys, bells, lights and foghorns can help you pin point where you are if using a chart. Attention to your speed, distance traveled and direction will be important in these situations.
You can use your topo map in the same manner. You won't have a compass rose to use, but you can improvise with a protractor; even draw a compass rose on the map, carefully to match the orientation. Make sure you are using the right declination. The magnetic ring of the rose is all you will need.
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