Wednesday, March 25, 2009

The Essential Systems: Navigation

Navigation is the first of the Fifteen Essential Systems for preparedness, travel, or hiking.

The checklist:

1. Compass(es)

2. Detailed street maps of home town and nearest large cities and the city you're visiting as a tourist or for business

3. Road map of state and neighboring states or a road atlas of the country

4. Map of local public transportation routes and timetable

5. Topographical maps

6. GPS receiver (optional).


1. Compass - A good compass is a baseplate compass marked in 1° or 2° increments with a clear baseplate, adjustable declination, a bezel that's easy to turn while wearing gloves, and is easy to read in dim light. A better compass is a mirror-sighting baseplate compass with the same features because you'll be able to get more accurate readings with it. The best compass for our purposes is a global mirror-sighting baseplate compass because you won't have to hold it absolutely level to get an accurate reading. The most reliable compasses are currently made by Brunton, Recta, Silva outside the U.S. and Canada, and Suunto.

(Silva in the U.S. and Canada is owned by Johnson Outdoors Inc. It used to sell reliable compasses made by the reputable Swedish Silva prior to 1998, but now sells compasses made by unknown manufacturers.)

Although compasses that have a fixed declination scale or no declination scale cost less than a compass with adjustable declination, it's well-worth spending the few dollars more. This isn't a feature you want to scrimp on because it's difficult to do calculations when you're stressed by disorientation, fatigue, cold, and hunger. Some people advocate placing a piece of tape on the compass to mark geographic north, but tape can shift and fall off. If you already have a compass that doesn't have an adjustable declination, the purchase wasn't a waste - keep it as a backup.

If you're in the U.S., the scales on the baseplate should include 1:24,000 (1 inch = 2,000 feet). Some compasses also have a 1:62,500 (1 inch = approximately 1 mile) scale. That scale won't be used much except with older maps because the U.S. Geological Survey 15-minute (1:62,500) map series is officially replaced by the 7.5-minute (1:24,000) series which is the best scale for topographical maps used by hikers because it shows critical details that smaller-scaled maps omit.

If you live outside the U.S. or your map's metric, look for a baseplate compass with the metric scales of 1:25,000 (1 centimeter = 0.25 kilometer) and 1:50,000 (1 centimeter = 0.5 kilometer). If you think you'll do the math necessary to convert from inches to metric, please don't count on being able to calculate accurately while under stress; your life is worth more than the expense of another compass.

If you read enough online or are around others who have used compasses, you'll eventually run across someone who swears that a lensatic compass is the best. It isn't necessarily true because a lensatic compass requires additional tools for use with a map that are already a part of the baseplate of a baseplate compass and since there's no declination adjustment on a lensatic compass, you'll have to do the math or learn how to orient a map which is so simple, someone with a baseplate compass that doesn't have adjustable declination should learn how to do it when out in the field.

Although some lensatic compasses do have a baseplate that would eliminate your needing to also pack a map tool or protractor and ruler, the baseplate may be short and you can't see through it to the map underneath like you can with a baseplate compass that has a clear baseplate.

If the argument is made that a lensatic compass is more accurate, you should challenge the statement by asking, "More accurate than what?" because not all baseplate compasses are created equal. For example, any compass with 1° or 2° increments is going to be more accurate than another with 5° increments. The bottom line is that a lensatic compass isn't any more accurate than a mirror-sighting baseplate compass. Another advantage to having a mirror-sighting baseplate compass is that it might also be used as a signaling mirror in a pinch.

Please don't get me wrong. I'm not against lensatic compasses. After all, I learned navigation with a lensatic compass. It's just that baseplate compasses are more convenient and easier to use.

Having written all that, I need to point out that the most important thing is being competent with whichever type of compass you choose because that basic skill is all you'll have when the chips are down. If you have your heart set on buying a lensatic compass, I recommend one by Cammenga which makes them for the U.S. military.

It's a good idea to have another compass as a backup such as a small or button compass to confirm what your primary compass is showing you when you don't want to believe it, as frequently occurs with disoriented hikers. The concept is that the majority rules: two compasses against one person's imperfect sense of direction. Practically any compass will serve as a backup as long as you know that it agrees with your primary compass before you start questioning its veracity. (Hard-headed people should have two backups to convince them to yield to their instruments.)

For a traveler flying from one city to go sight-seeing or attend business meetings in another, a small compass is useful to get oriented when exiting a subway or train and to avoid getting lost on narrow, winding streets with high walls or tall buildings that prevent you from spotting a landmark. Good, inexpensive, compasses for this purpose are those such as the Brunton Traveler which may be threaded onto a cord worn around your neck and the Suunto Clipper which comes with its own wristband or may be clipped onto watch bands up to 22mm wide.

The Suunto Clipper is available in two versions, non-luminous and luminous. The non-luminous version is black with a blue face. The luminous version is black with a white (luminous) bezel and points.

If you live in the northern hemisphere and travel to South America or Australia or vice versa, you're supposed to have a compass that's balanced for the zone you're in especially if you go hiking. Most people buy a compass when they arrive at their destination. However, the compass you have for your Essential Systems preparedness pack might work fine and not drag or hang up when you go south/north of the equator. So, go ahead, take it with you and see if it works before shelling out your hard-earned money for a new compass.

In 2005, Suunto got the five zones down to two zones where their compasses work for either the northern or the southern hemisphere with some overlap and then developed global compasses that work for both hemispheres such as the M-3G and MC-2G models. (If you buy another brand, Zone 1 is pretty much the entire northern hemisphere, the U.S., Canada, Europe, etc., meaning that you won't have to buy another compass when you travel to another region in the northern hemisphere.)

In case you're wondering, there's no need to be concerned about the upcoming geomagnetic flip because it will take much longer than our lifetimes (experts guestimate 500 - 2,000 years or more) to reach the point where the North and South poles begin to exchange places. Besides, the flip won't happen overnight or even over the course of a year. It will take perhaps thousands of years, long enough for the future generations to learn how to adapt and cope.

2. Detailed city street maps - if you need to go somewhere you're not familiar with during an emergency, having good maps already at hand will save you from considerable stress. I recommend that you also provide each child in your family with a city map or a copy that has the homes and/or workplaces of trusted friends and family marked on it so they know where to go if they ever become separated from you. Store their maps in plastic zip bags in their school bags or backpacks so they always have it with them.

For traveling to foreign countries, get dual-language maps before you go, if possible, or wait and buy a good map at your destination. It'll be easier because what we know in English, for example, will likely be a different word in the foreign country. Figuring out that Roma is Rome is easy enough, but what about Firenze? It doesn't look or sound anything like Florence. You need to be able to recognize signs and, if you ask residents for help with directions, English labels might not mean anything to them. If you can't locate a dual-language map, get the map that uses the foreign language and get used to the different names.

3. State road maps - same rationale as for the detailed city street maps. Please be aware that not all maps are created equally. For example, in 2006, the official state map of Georgia eliminated 488(!) communities. Maybe there wasn't much there other than a volunteer fire department and a store with a gas pump, but if you're low on gas, want some food, or need help, if I were a betting person, I'd bet in a heartbeat that you'd want a map that shows the location of the closest communities and what kind of road you'd have to travel to get to one of them.

If you have children, giving each child a copy of your road map with the route of your road trip highlighted will give them something to do as they look for signs that match the towns on their maps and will alleviate the "Are we there, yet?" questions because they'll be able to see on their maps how much farther you have to go. It's also an easy way to get them used to reading maps.

4. Public transportation routes and timetable - same rationale as for the detailed city street maps in case you can't drive for any reason.

5. Topographical maps - These are essential for hikers and other people who drive through wilderness areas. Fold the map and store it in a map case or a gallon-sized zip freezer bag.

I've found that National Geographic and many gift stores in U.S. recreational areas such as the National Park System sell USGS topo maps that are scaled 1:100,000 (30-minute) or smaller at 1:250,000. Please do not buy any of these for navigational purposes. The scale is so small, with so many details omitted, that you're bound to get confused trying to match your surroundings to the map and may get lost even though you do everything else right. Look for a 7.5 minute map (1:24,000) or metric equivalent (1:25,000) if you're outside the U.S. Boaters will need nautical charts instead of topo maps.

[Hint: One way to fold a map is to fold it in half, then fold the ends in to the middle fold accordion-style, and finally in half or in thirds lengthwise to get it down to a manageable size. This will enable you to view any portion of the map by unfolding sections without having to unfold the map completely.]

To obtain free index maps for each state, "Topographic Map Symbols," a free brochure interpreting the symbols used on USGS topo maps, catalogs, and to order topographic maps from the USGS, contact:

USGS Information Services
Box 25286
Denver, CO 80225
1-888-ASK-USGS or 303-202-4700
Fax: 303-202-4693
Web site:

or use the USGS Map Locator to find, order, or download maps.

You may also download free index maps from GeoMart and OmniMap.

The publishers of topo maps for several other countries are listed at Wikipedia.

6. GPS receiver (optional) - As wonderful as GPS receivers are, you must know how to use a paper map and compass. You can NOT rely on a GPSr because batteries get drained, the unit's inability to see the satellites due to natural or urban canyons or dense tree or cloud cover, or other misfortune such as accidentally dropping and breaking it. Sure, compasses can break, too, however unlikely that might be considering they're made of acrylic or polycarbonate.

Speaking of plastic, you should go easy on the DEET because if it's strong enough, it will melt plastic. Be sure to wash it from your hands after applying it or use another insect repellent such as Picaridin, oil of lemon eucalyptus, or Permethrin that you spray onto clothing and let dry before wearing.

What many people who eschew compasses in favor of GPS receivers are ignorant about is that as long as the compass needle isn't damaged, it will still work. Even though the capsule is broken, it doesn't necessarily mean that you're up a creek without a paddle. You may have to wait longer for the needle to settle, or you may have to float it on a leaf or some other Plan B technique, but - HA! - try any of those with a broken GPSr and see what good it does you because once a GPS unit is broken, it's totally useless as a navigational device.

Besides, you have a backup compass, right?

Also, even though the geomagnetic flip won't occur for several generations, the New York Times reported on July 13, 2004 that satellites are being damaged and having electronic malfunctions from the declining magnetic strength. Of course, the problem was immediately addressed, but it takes time to effect a modification, better shielded satellites, perhaps. That's just another way that the GPS system might fail you and another reason for you to learn how to use a map and compass.

Some states, such as Oregon, have hefty fines for those who require a SAR effort and who don't have a topo map and compass with them. Another reason to not rely solely on a GPSr is that other states such as Colorado, ski areas in Idaho, and a county in Utah, may seek reimbursement for rescuing people who get lost.

We need to bear in mind, too, that what was given to us civilians, by discontinuing Selective Availability on May 2, 2000, may also be rescinded without notice for reasons of national security because the U.S. Department of Defense controls our Global Positioning Satellites.

Along that vein, travelers from the U.S. going to another country need to be aware that some countries consider GPS receivers to be restricted military equipment. To avoid unpleasant issues, be sure to check before you go to another country with your receiver.

What do you do after you accumulate the items on this checklist - sit around, waiting for an emergency situation requiring the use of them? No, I wouldn't let you read this far only to leave you hanging.

The first thing, of course, is for you to learn how to use your compass with a topo map. The USGS has a webpage for "Finding Your Way with Map and Compass." After reading it, especially if it seems as clear as mud, please go to your public library and check out books about navigation that are easier to read and comprehend. The library books will have exercises to do along with navigational tips and tricks that will compensate for any error introduced by inaccurate readings.

One point I want to bring out while I have your attention is that compasses use magnetic north while maps use geographic north. There are two ways to make them match.

The first, and by far the easiest method, has you setting your compass to match the map by adjusting the declination setting on your compass. That's it; find your declination value, then set it and forget it. There's no downside. You'll have to check the declination value at least annually and adjust your compass periodically, but until it changes more than, say, a half of a degree for a compass with 1° increments or a degree for a compass with 2° increments, your compass will read geographic north just like your map.

The second method has you matching your map to the compass. You can convert the map's geographic north to the magnetic north of your compass by drawing lines that are parallel to the angle of the declination value. It's a pain, especially on a trail with the map flapping in the breeze, and it has to be done with every map you use. Additionally, you'll have to buy new maps and redraw the lines whenever the declination value changes or before drawing the new lines on old maps, erase the old lines that you were smart enough to remember to draw with a pencil.

To be thorough, you should learn both methods. In practice, adhering to the first method, converting your compass from magnetic north to the map's geographic north by adjusting the declination, is the way I advise you to go no matter what whichever books you read tell you to do simply because it's easier. (I can't believe some teacher-authors don't even teach the first method and make their students and readers use the second method which is so much more inconvenient.)

After you've done the examples in the books in your local library, I recommend that you teach your children how to navigate. To practice, first make a map and set up a course or few in your backyard before progressing to a larger area like a local park and using a topo map. From there, you can maintain proficiency by engaging in one or more of the following activities that use a map and compass:

Geocaching - while most people use a GPSr to help them find the "treasure," there are those who use only a map and compass.

Orienteering - formerly a competitive sport only, orienteering now allows participation by those who want to stop and smell the flowers at their leisure.

Rogaining - long-distance navigation requiring teamwork

Waymarking - like geocaching except the "treasure" is a place to see.

If you practice staying found with a map and compass, you'll never get lost!

[The next article in this series is "The Essential Systems: Personal Attire."

The first article in this series is "Preparedness: Introducing the Fifteen Essential Systems."]

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