Any good handheld compass is still only accurate to within two or three degrees. Accuracy in compasses means how close to the actual bearing will the magnet on the north seeking arrow point. It is a more precise instrument because of this sighting arrangement, but the lens does does not make it more accurate than a base plate compass. Practice.Ī “lensatic” compass is named such because it has lens on it to view your degree marking when you sight on a landmark along your desired azimuth. The terrain features traveled through and knowledge of a few simple helpful techniques will show you the way to most any practical destination outside of military precision. For most needs of land navigation through average topography featured woodland or open terrain, attempting to read and follow a compass bearing accurate to better than two degrees is futile and unnecessary, regardless if using a cheap bare baseplate, a more expensive mirrored version, or a rugged bullet-proof military lensatic. Terrain association techniques take practice to perfect, The ability to translate a flat 2 dimensional map into 3 dimensional landscape of your surroundings, and also do the inverse from visual observations is what you strive to do. Learn how to use topography of handrails, catches, backstops, and easy to identify fixed terrain features (both on map and on earth). Or something that is bigger than the hole in the tool.Īdditional techniques for plotting a bearing.UInless in featureless tundra or desert where all terrain is the same as far as you can see forever, most successful navigation is done by map reading and terrain association, with assistance from a compass for general direction finding. If your string is too short to make a loop, tie the end to a small twig, a button, Some folks like red thread, others prefer black, and some want a loop of thin elastic cord. ![]() Sewing kit, a thread from the core of a piece of para-cord, dental floss. Some field expedient string sources include, thread from a Line it up with the bearing on the edge of the protractor, and use the straight lineĬreated by the thread to follow the bearing away from the edge of the protractor. Longer that twice the distance you might want to extend a bearing.) Pull the string tight, String through the center hole and tie the ends together. Tools with protractors have a hole in the center. This is what we demonstrated in the above example.Īnother technique is to use a piece of thread to show your bearing line. Draw a line between these two points, and extend it asįar as you need to. Now place a straight edge between the known point and the mark you One of simplest techniques is to place a small pencil mark on the correct bearing at theĮdge of the protractor. Techniques for extending the bearing line The center of your protractor will be at the intersection of a line drawn between 0° and 180° and a line between 90° and 270°ĭetermine what lines to use to align your protractor with your north reference lines on your map.Ī protractor that is well suited for navigation will have numerous parallel lines aligned with 0° to 180° on the protractor. You will place the center of the protractor on the known point where you are plotting your bearing. Some protractors are numbered in four 90° quadrants,Īnd are a probably not a good choice for navigation use.įind the center point for your protractor. Make sure you use the correct set of numbers. You proceed in a clockwise direction? Many protractors used for drafting are numbered in both clockwise and counterclockwise directions. ![]() Is you protractor marked in degrees? Are the marks spaced at one, two, or five degrees? Is it a full or half circle protractor. 0° (and 360°)Īre aligned with our north reference, 90° is to the East, 180° to the South, and 270° to the West. Familiarize yourself with your protractorīefore you set you protractor down onto the map, take a good look at it and make sure you understand the markings.įor navigation purposes, we use an angular measurement system where a circle is divided into 360 degrees.
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