How to use a compass like a master navigator
Have you ever been so lost in the sauce that you needed a compass to find your way out?
Technology like handheld GPS and navigation apps are wonderful to have, but anyone seeking adventure in the great outdoors should have a working knowledge of old-school navigation methods that don’t require batteries or connectivity. Whether you plan on hiking, camping, hunting, fishing, or prepping for the zombie apocalypse, you’d better learn how to navigate with a good old-fashioned compass and map.
Task & Purpose’s editors prepared the ultimate down-and-dirty guide on the right way to use a compass. Let’s get started.
Doing it right with a lensatic compass
Time You’re Going to Need: At least one hour per practice session
What you need to know about using a compass
Being able to use a compass is one of the most basic elements of navigation. Before you give it a try, familiarize yourself with your map’s scale and key. Know how to convert grid north to magnetic north. Plot start and endpoints as accurately as possible, and rely on the map’s grid lines and your protractor to identify the direction you need to travel.
Once you understand how to read a map and interpret things like contour lines and terrain features, it’s time to put that knowledge to use by navigating from point to point without GPS or the aid of your phone. A compass can be a life-saving tool, but it’s also useless in the wrong hands. Make sure you know how to use one by practicing regularly and testing yourself with increasingly difficult challenges.
How does a compass work?
In the most basic forms, a compass is made up of a floating dial marked with an arrow that is drawn to Earth’s magnetic north. With that single piece of information, you can get a rough approximation of your bearing. Any compass worth carrying will include degree markings for more precision. More markings mean more accuracy, and we recommend finding a military-style compass that shows 360 degrees.
Don’t bother getting carried away with minutes and seconds (60 minutes per degree, 60 seconds per minute). A fixed index line will show the compass body’s orientation in comparison to the floating dial. Beyond these basic components, there are a few key features that we recommend shopping for and learning to use effectively.
Most compass faces are smaller than the palm of your hand, and marking 360 degrees on a circle that small can make things tough to read. A magnifying lens will let you get more accurate readings.
If you plan on relying on a compass for real-life navigation, you’ll need to do better than a simple floating dial and index line. Sighting systems let you visualize your desired orientation (known as shooting an azimuth) by aligning front and rear sights to identify the exact point in the distance you need to reach to travel in the right direction.
A bezel ring will let you set your course once for future reference and prevent you from making costly errors later. Military compasses use a notched bezel ring that moves three degrees with each click. For example, to shoot a 30-degree azimuth, you’d rotate your bezel ring ten clicks counter-clockwise. From that point forward, lining up your bezel ring’s short line with the magnetic arrow would aim your compass sights directly toward 30 degrees.
A compass that glows in the dark can be effective at night or in other low-visibility situations. Military compasses use tritium, which does not need to be charged by exposing it to light, to provide luminous markings at key points like magnetic north, the bezel ring, and front sight to aid in night navigation.
A thumb loop will help you hold your compass steady when shooting an azimuth. Using a compass accurately requires precision, so take all the help you can get.
Mutually assured compass safety
You can’t earn a Purple Heart in the garage, so there’s no need to put yourself at risk. Ensure you come out the other side by following the directions, taking your time, and understanding that what we’re doing here can be dangerous. Keep your awareness up and you won’t need stitches—maybe.
Compasses aren’t dangerous, but getting lost damn sure is. Practice navigating in a familiar area. Use catching features to prevent you from getting too far off course; for example, a park that is surrounded on all sides by roads will keep you in the correct general area. Having a backup navigational aid like a phone isn’t a bad idea, either. As always, be smart about water crossings. Find a safe place to cross or map out a dogleg around hazardous areas.
What you’re going to need to use a compass
Everyone has different gear in their kit. Make sure you have the best tools of the trade on hand for this specific task. Don’t worry, we’ve made a list.
- Gotical UTM/MGRS map protractor
- Staedtler map pens and eraser
- RedVex pace counting beads
- Rite in the Rain weatherproof notepad
The compass brief
We hate to bring bad news, but the maps and globes you’ve seen all your life haven’t been completely straightforward with you. When you aim a compass north, it isn’t pointing where you think. Magnetic north (zero degrees on your compass) doesn’t necessarily point to true north (due north on your map, the north pole on a globe). In fact, Earth’s actual magnetic north lies somewhere in northeast Canada.
Maps intended for navigational use will provide a declination that tells you the difference between true north and magnetic north so you can make a quick calculation to convert your map readings into compass readings; and vice versa. You can also use this National Oceanic and Atmospheric Administration tool to find the most accurate declination for a specific point.
Taking a bearing in the field
Military compasses provide a great example of how to use a compass effectively, so that’s the example we’ll use. Besides, if you’re reading this, there’s a good chance you have fresh second lieutenant bars and an upcoming land nav evaluation with a compass just like this.
- Start by plotting start and endpoints on your map as precisely as possible. Using a map protractor, determine the correct direction of travel.
- Use the appropriate declination to convert the reading on your map to the reading you’ll use on your compass.
- Set your bezel ring to obtain a quick, reliable reading. Do this by aligning the fixed index line with your bearing on the floating dial and rotating the line on your bezel to magnetic north, or by calculating the number of clicks away from zero degrees north you need to rotate the bezel to achieve the same result. For bearings of one to 179 degrees, rotate the bezel counter-clockwise. For bearings of 181 to 359 degrees, rotate the bezel clockwise.
- With your bezel ring set, stand at your starting point and raise the compass sights to your dominant eye. Confirm that the north-facing arrow lines up with your bezel ring’s short line. The point you see through your sights is the point you need to reach to travel in the desired direction.
With practice, you’ll be able to move with the terrain to travel quickly and efficiently without sacrificing accuracy. To start, though, stick to short distances and travel in a straight line. See how close you can get to a predetermined point by shooting and following an azimuth. Gradually increase difficulty by throwing in more difficult terrain and longer distances. Be aware of your tendencies. Does your pace lengthen or shorten based on terrain? Do you drift to the right or left? Know the answers to these questions before you hit the end of your first leg in a land navigation test and find yourself without a point in sight.
A navigator’s pro tips for using a compass
Because compasses are magnetic tools, it’s critical that you remember to check your surroundings for things that can interfere with their operation. Metal objects as small as a rifle can throw off your compass readings. Vehicles and power lines can be especially disruptive. Distance yourself from large metal objects to get a more accurate reading.
Once you shoot your azimuth, walking directly on it is an effective–but tedious (and sometimes impossible)–technique. If you choose this method, selecting nearby reference points or limiting travel to about ten paces in between re-sighting can improve accuracy. Be aware of how terrain features like slopes and ground surfaces affect your gate.
We recommend using a combination of compass readings and terrain features to navigate. Start by identifying a fixed object along your azimuth and walking to it using the most efficient route. If you can see a reliable midpoint, you can avoid making deep river crossings and struggling through thick underbrush just to keep moving in a straight line.
Night navigation can make it impossible or impractical to use the sights on your compass with the compass-to-cheek method. When that’s the case, you’ll need to hold the compass against your torso at the bottom of your rib cage and perpendicular to your body. Luminous markings will let you get your bearing and point you in the right direction. Remember to keep the compass tight to your body and turn using your feet, not your waist.
A POG’s FAQs about using a compass
Q. How much does a compass cost?
A. Basic, serviceable compasses can be found for less than $20. These are fine for brushing up on your skills on your own time. For serious land navigation, you’ll want something closer (or identical) to what the military issues. Lensatic compasses with tritium are your best bet. You can land one of these for around $100.
Q. Do I seriously need to bother with this old thing?
A. Yes. Apps and Blue Force Trackers are great, but they rely on technology that can–and will–fail at some point. Carrying a few extra ounces in a compass pouch is cheap insurance. Besides, the skills you develop navigating the hard way will make you far more proficient with other tools.
Q. What type of compass is best?
A. Lensatic compasses provide far more accurate readings than basic compasses. Being able to read bearings with one-degree accuracy and visualize your next waypoint with a sighting wire will always be better than glancing at a flat compass and guessing at your general heading. Durability is also important. Look for metal compasses, laminated maps, and weatherproof notepads.
Q. What is tritium and do I need it?
A. Tritium is a rare, radioactive material that glows in the dark. Unlike cheap paint, it doesn’t need to be exposed to light to charge and it lasts an incredibly long time. If you can afford a high-end compass that includes tritium on the floating dial and sighting system, we can’t recommend it highly enough.
Got questions, comment below & talk with T&P’s editors!
We’re not saying you’ll definitely get lost and end up crying in the woods when you start learning to use a compass, but it can happen. Maybe pack an overnight bag, just in case.
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