Find Your Way

A series of articles dedicated to the lost art of land navigation and map reading

Determine your pace count

By H-Minus

Our last article discussed how to determine distance and direction on a topographical map. We touched on map scales, the difference between grid north and magnetic north. We even did a little bit of basic math…

Oh how I hate math…

This article will provide you with some tips and tools to help you determine distance by the number of steps you take. It is called a pace count. If used in conjunction with other land navigation skills, it can be a pretty accurate way to determine distance traveled in the woods. Many things can determine the way you walk. Age, fitness level, height, weight, ground conditions are just a few. To establish a pace count, one must try to simulate as many of these variables as possible. For instance, if you expect to do most of your land navigation with a pack on, then it stands to reason that is how you should determine your count. It has been 28 years since I first walked the line to establish my pace count. When I started writing this article, I decided that it was time to see if it still the same. At 46 years of age, I might be in for a little surprise.  Don’t get me wrong, I am in pretty good shape. I just think that back in the day, I spent more time in the bush than in the rear. I was more at home in the woods and it likely showed in how I moved. Now I might be a little more cautious when stepping over rocks, or crossing a stream. So, this summer, my goal is to establish a new pace count. Some of you may already know that soldiers and marines sometimes had two types of pace counts. One was a regular count for normal terrain and the other was what we called our Jungle count. Mine was discovered while attending JWS in Panama back in the early 80’s. We adapted that count for very difficult terrain. I don’t use it these days, but it is an option. The typical measurement for a pace count is in Meters. The equation goes like this (X = number of steps in 100 Meters). For me X=120. For every 120 steps (counting every step), I will have traveled 100 meters. If you remember in the last article, we determined distance on a map in meters. In fact, I believe the distance we determined on our map was 3400 meters. WOW! How many steps is that. Let’s see… 120 x 10 = 1200 steps in 1000 meters, then multiply 1200 times ???…. Oh forget it.. there is no way I can count that many steps. Lets try a different approach to recording your pace count. There is a handy little tool that you can easily make and will help you remember your count for several thousand meters. It is called a Pace Cord. It only requires a little 550 cord, some craft beads and a lighter. The typical Pace Cord has two sections. The upper section has several beads separated by a knot leading to the lower section. The lower section has more beads. The beads on the top of your cord represent 1000 meters for each bead. Each bead on the lower section represents 100 meters. As you count your steps and reach the 100 meter mark, you will move one of the beads on the lower section down. Once all the beads on the lower section are in the down position, you will move one bead from the upper section down. You will then move all the beads on the lower section – up and start over. There is some debate over how many beads should be on the bottom, but let’s simply use 10 beads.

Constructing your pace cord is very easy. Get out your handy 550 cord and cut a small section to take to the craft store. Find the bead section and look for the type and size you would like to use. Make sure they slide on to the 550 cord with some resistance. You don’t want them moving about while you are in the woods. I placed 15 beads on my length of 550 cord. 10 beads for 100 meter increments and 5 beads for 1000 meter increments. Tie a knot on the bottom of the cord and use a lighter to lightly burn the knot. This will keep it from loosening up. You will then separate the beads into tow sections. 10 on the bottom and 5 on the top. Tie a knot between the beads and leave some room for bead movement. Heat the knot, tie a loop at the upper end and heat it too. Now you have a working Pace cord. You can attach this anywhere you wish. The next step is to find a place to count your steps. A good rule of thumb is to walk a known distance over 100 meters and count each and every step. Let’s say you plot a 400 meter route and count each step. At the end of your travels, you simply divide the number of steps by 4 and you have an average pace count for 100 meters. For those of you with a GPS, all you would need to do is set a starting point with the unit, walk several hundred meters using the device and do the math. Most GPS units will show you distance traveled. Use that to record the number of meters. Another way is to use Google earth to plot a route, walk the route and record your steps.

Google earth is a great tool for navigation and reconnaissance. You can download the program for free at:

http://www.google.com/earth/index.html

Find a location with two easily identifiable landmarks with an even distance between them. In this instance, I picked two road intersections on a plot of land near my home.

Next, use the “ruler tool” in Google Earth to plot you line. Start your line near a known point that you may easily identify. In this case, I set my start point about 20 meters in the wood line near a road intersection. My ending point is at a small clearing next to a dramatic turn in a road. The entire walk will be in the woods, with two streams and patches of dense underbrush. Now I will use the “ruler tool” in Google Earth, to see what the distance is. Lucky for me, the distance is slightly over 600 meters and the direction is parallel to a highway. I can’t get lost! To find my pace count, I would simply walk from point A to point B using my compass set at 176 degrees and record each and every step. At the end of my trip, I will then take the total number of steps and divide it by 6. That will be my average pace count for 100 meters. Example: Let’s say walking the above route takes me 755 steps total. I would simply divide 755 by 6. 755 ÷ 6 = 125.83 steps or 126 steps. The “Google” method is at the moment unproven, but I feel confident that it will work. If you do not feel comfortable using Google to find your count, you can simply run 100 meters of string in the woods and estimate your count that way. This concludes the 4^th article in the “Find Your Way” series. Please check back soon where we discuss how to use landmarks to help you stay on track. Thanks and see you again soon, H-Minus

Find Your Way

A series of articles dedicated to the lost art of land navigation and map reading

Distance and Direction

By H-Minus

You have learned how to find your location on a map by using coordinates. This article will discuss determining distance and direction on your map. To do this, we will need to look at the legend portion of our map. This section is located at the bottom of the map. The two areas of the legend we will focus on are the map scale bar and magnetic declination.

Scale Bar

Magnetic Declination

Before we start, let’s point out the cardinal directions on every topographical map. If you have a map in front of you, the top of the map will always be NORTH. The bottom will always be SOUTH. The right side of the map will always be EAST. Lastly, the left side will be WEST. Assume you know exactly where you are on the map. You can point your finger to the exact spot on the map in front of you. Great… you know where you are on the map and you also know where you want to go… If you look in grid square 15 – 82, you will see a symbol that looks like this:

Remember to read right and then up…..

We know where we are on the map. We know where we want to go… but… How do we get there? We need to know what direction in degrees and distance in miles, feet or meters to go. We are going to compute our distances in meters simply because when we start on the land navigation portion of our articles, we will show you how to establish a pace count to estimate distance traveled. Let’s start with the easy part… How far is it from where you are to where you want to be? We will also assume you are going to navigate the distance as a crow might… A straight line… To figure out how far it is from point A to point B, we need only a pencil and paper. Mark the two points on the paper and use the scale of the map to estimate the distance. As you can see, the zero mark on this particular map scale is not quite where are points are drawn. In this case, all you need to do is use the smaller scale to the left of zero to determine the number of meters needed past 3000. In this case it is about 350 to 400 meters. Our total distance would be 3400 meters from point A to point B. We know that our trip will be a distance of 3400 meters. Our next question is what direction we need to go to get there.

Your compass is set up in degrees.

Your protractor is also has a degree scale.

In order to establish direction you will need to first plot a line of travel. Take a straight edge and draw a line from the starting point to the destination. If the distance between point A and B are relatively close, extend your line past the destination point. This extension may be needed to help you determine direction with your protractor. Once the line indicating direction of travel has been drawn, place the protractor squarely and centered on the map, with the crosshairs of the protractor right on top of the starting point of your line. Read the direction in degrees from the point where the line intersects the degree scale on the protractor. Just make sure your protractor is placed properly on the map. It is correctly placed if zero 0 degrees faces up, 90 degrees to the right, 180 degrees down, and 260 degrees left. The result will look like this: This is how you establish direction in degrees on a map. There is still the issue of converting your direction from grid to magnetic. Remember, most maps have a magnetic declination and it requires a conversion from grid north to magnetic north. That difference is also measured in degrees. The legend portion at the bottom of your map will have that difference noted. The conversion is pretty simple. It is simply a matter of adding or subtracting the G-M angle from your grid direction. The difficult part is figuring out if you have to add or subtract. That will depend on whether or not you have an easterly or westerly G-M angle.

Easterly G-M Angle

Westerly G-M Angle

There are very few things about land navigation and map reading that I have to write down. This is one of them. To make the conversions remember this:

• Easterly GM angles: Grid to magnetic subtract, magnetic to grid add
• Westerly GM angles: Grid to magnetic add, magnetic to grid subtract.

A good place to write this down is in permanent marker on your protractor (if you have room) or on your map case somewhere. Don’t try to remember it. In 27 years of doing and teaching this stuff, I can’t remember. Now back to our map. Our last calculation was a grid direction of 52 degrees. Remember, that was grid degrees. We now need to know what our compass direction should be to get to point B. The legend of our map shows a 5 degree G-M angle in an easterly direction. To convert an easterly G-M angle from grid to magnetic, we must subtract the 5 Degrees from the 52 degrees plotted on the map.

52 – 5 = 47

Alright! We now know that we have a direction of 47 Degrees on our compass for 3400 meters to get to our destination. And off we go…. We are walking, looking at our compass, walking, looking at our compass, and walking… wait… how far have we gone? I don’t know. I thought you were keeping track. In fact, how do I know how many meters I have walked? That is another subject. See ya soon.

Find Your Way – True Grid

A series of articles dedicated to the lost art of land navigation and map reading

By H-Minus

I am a big fan of old westerns. John Wayne and Clint Eastwood were the quintessential cowboys. As a kid, I would imagine being on horseback in the wilderness. Me and the Duke gunning down a bad guy, wanted for some unspeakable crime… I would spend Saturday afternoons watching a drunken, U.S. Marshal and his Texas Ranger sidekick tracking the murderer of a young woman’s father. Or a Sunday Spaghetti Western, with the trio: Clint , Lee and Eli (AKA The Good, The Bad ans The Ugly) attempt to find stolen Confederate gold. Something always bothered me about those movies… How did these guys know where to go?… There were no roads, at least not in the movies.. So how did they know what direction to travel and how did they know how to get back home? There are some people who have a great sense of direction… I am not one of them… Even with a map and a compass, I have a difficult time getting from point “A” to point “B”. Some of us not as directionally superior as the hero’s of those old westerns. We need help! The last article discussed the “Five major” and “Three minor” terrain features associated with a map. We also touched on “Grid North” versus “Magnetic North”. This article will discuss how to establish a grid coordinate as it relates to map reading. Maps typically have one of three ways to establish a location: Latitude and Longitude Coordinates:

The geographic latitude of a point on the Earth’s surface is the angle between the equatorial plane and a line that passes through that point and is normal to the surface of a reference ellipsoid which approximates the shape of the Earth. The North Pole is 90° N; the South Pole is 90° S. The 0° parallel of latitude is designated the equator, the fundamental plane of all geographic coordinate systems. The equator divides the globe into Northern and Southern Hemispheres.

The Longitude of a point on the Earth’s surface is the angle east or west from a reference meridian to another meridian that passes through that point. Latitude and Longitude is displayed in degrees, minutes, and seconds.  To be perfectly honest with you, I know very little about longitude and latitude.

Example:

Universal Transverse Mercator (UTM): The UTM system is a geographic coordinate grid-based method of identifying locations on the surface of the Earth. A position on the Earth is referenced in the UTM system by the UTM zone, and the easting and northing coordinate pair. The easting is the projected distance of the position eastward from the central meridian, while the northing is the projected distance of the point north from the equator (in the northern hemisphere). Eastings and northings are measured in meters. When interpreting a UTM grid you will read right (east) and up (north).

Example:

Military Grid Reference System (MGRS): This is the standard reference for the US military and NATO. It is also the one that I am most familiar. Unfortunately, USGS maps are not marked with MGRS. MGRS is derived from the UTM (Universal Transverse Mercator) grid system, but has a different labeling as that used by UTM. A MGRS consists of three parts.

1. A grid zone designator, GZD.  These are zones, numbered 1–60 and are intersected by latitude bands that are lettered.The intersection of a UTM zone and a latitude band is called a grid zone, whose designation in MGRS is formed by the zone number (one or two digits – the number for zones 1 to 9 is just a single digit, followed by the latitude band letter. This same notation is used in both UTM and MGRS. An example of a grid zone designator migh would be: “1Q” or 2”N”.
2. 100,000-meter square identification. This is a lettered method of identifying a 100,000-meter square area of the earth. This is what most drunts pay attention to when goingoff map. The 100,000 – meter swuare identifyer, lets you know what the next map sheet will be. It is identified by letters. An example may be “FJ” or “AL”.
3. The third part of an MGRS coordinate is the numerical location within the 100,000 meter square, indicated by numbers up to a 10 digit cordinate. A ten digit cordinate will give you a potential accuracy of up to 1 meter. The fewer digits, the less the accuracy. In the case of a 10 digit cordinate, The first five digits represent the easting in meters . The second five digits would represent the northing part of the cordinate.

Example:

We will focus on UTM grid zone designators. Simply, because it is what 99 percent of us will encounter with maps originating from the USGS. You may remember from the last article that I spoke of maps that may not have grid lines marked. If you find that your map does not have grids, you can mark them with a straight edge, pencil, and steady hand. One thing to remember when reading a grid, is to always read the numbers from left to right and then up.

Example:

If you notice the helicopter on this map, you will see it lies within a square or grid on this map. This grid is represented by two coordinates, or sets of numbers. One set of numbers goes from left to right as seen at the top of the image. The other goes from the bottom to the top as seen on the left side of the image. These represent the northerly and easterly grid lines as discussed earlier. You will see the number 17 3 73 000 represents the easterly grid line for the helicopter. The three zeros at the end of this grid refer to 100 meter markings within that grid or box. Since we are not sure where the helicopter lies within those 100 meter boxes, we can leave the zeros off for now. We will get to those numbers as soon as we determine what grid square our helicopter lies in. So, we know that the helicopter is within the 17 3 73 easterly part of the grid, now lets determine what the northerly grid is. Looking at the left side of the map, you will see a series of numbers going up in a northerly direction. This is the second half of your grid. In this case the helicopter lies in the 39 47 grid location.

If you put the two grid coordinates together you would have this:

17 3 73 E

39 47 W

You now have a grid location with 1000 meter accuracy, or as they say in the military “one klick”. A Klick is equal to a kilometer. Being the high speed land navers that we are, we want better accuracy than one klick. That is where our cool UTM grid tool comes in handy.

This clear plastic measuring device will help us determine a grid coordinate to at least 100 meters. You can even get accuracy to 50 meters or less by simply making an accurate guess to points falling within the little 100 meter blocks. Once you determine the grid square coordinates, you simply duplicate the routine using the grid tool. Remember to read right and then up.

RIGHT

THEN UP

GRID

17 3 73 650 E

39 47 400 N

Based on our calculations, we now have a grid location for the helicopter with an accuracy of at least 100 meters. It is more like 50 meters given the fact that our easterly part of the grid ends with the number 50. That pretty much covers the basics of obtaining a grid coordinate. For those of you who like to practice, there is a fun way to incorporate this into a cool hide and seek game. Find an easily obtainable location on a map, perhaps near a known road intersection. Hide a geocache near the intersection and give the grid coordinate to friends or family. Have them do the same for you. Use your new found map reading skills to find the cache and recover the items. As you get more skilled, look for local Geocaching clubs and find more difficult caches. I still wonder how cowboys made it around the wilderness without these tools. Were they so geographically inclined, they didn’t “need no stinkin maps?” Or was the map and compass a dirty little secret kept in saddle bags of cowboys everywhere? Well all cowboys except for Big bad John and Dirty Harry.

Keep your powder dry.

Continued from Introduction To Maps:

The Grid-Magnetic angle (or G-M angle) value is the difference between grid north and magnetic north. It is an arc, measured in degrees between the grid north and magnetic north lines. This value is measured in fractions of degrees, with mil equivalents shown to the nearest 10 mils. The G-M angle is important to land navigation because azimuths between map and ground should be adjusted to compensate for this difference. If not, you may be off by hundreds of meters before you get to where you are going. We will get more in depth on this on this in a future article. Terrain features of a map can be difficult to understand when looking at it from a two-dimensional perspective. The best way to describe the terrain features indicated on topographical maps is to approach it the way I was taught. Features were broken down into five major and three minor terrain features. The five major terrain features are: Hill, Ridge, Valley, Saddle, and Depression. The three minor terrain features are: Draw, Spur and Cliff. The best visual representation for these features is to get your map and compare the feature on the map to the actual land mass.  For now, let’s look at some army training aids. Five major terrain features Hill: A hill represents a point of high ground with sloping features going downward. You can also observe elevation markings on the contour lines indicating the hills sloping nature. Valley– A valley is a semi-flat piece of ground bordered on the sides by higher ground. A valley may contain a stream. The contour lines indicating a valley are U-shaped and sometimes will parallel a stream. Ridge- A ridge is a sloping line of high ground. Contour lines forming a ridge tend to be U or V-shaped. The closed end of the contour line points away from high ground. I like to remember this when trying to determine if I am looking at a ridge or valley… “valley toward,” “ridge away.” That means the U or V is going toward the high ground on a valley and away from high ground on a ridge. Saddle. A saddle is a dip between two areas of higher ground. A saddle is typically found between two hilltops. It can also be a dip along a ridge line. If you are standing in a saddle, you will see high ground in two opposite directions and lower ground in the other two directions. Depression. A depression is a low point in the ground. A good example of a depression would be a quarry. I depression is pretty much a hole in the ground.  On your map, a depression will show closed contour lines with tick marks pointing toward low ground.

Three minor terrain features

Draw. A draw is kind of like a small version of a valley. The exception being that in a draw, there is little or no level ground. You will likely find the draw a difficult feature to traverse. If you are standing in a draw, the ground slopes upward in three directions and downward in the other direction. A draw could be considered as the initial formation of a valley. The contour lines depicting a draw are U-shaped or V-shaped, pointing toward high ground. Spur. A spur is a short, downward sloping line of higher ground. You will typically find a draw formation protruding from the side of a ridge line. You may also find two parallel streams flowing down the side of a ridge. These streams will often form the spur. The ground sloped down in three directions.  Cliff. A cliff is self explanatory. I am sure we all know one when we see it. When viewed on a topographical map, the contour lines will come together into one contour line; this last contour line has tick marks pointing toward low ground. Cliffs are also shown by contour lines very close together and, in some instances, touching each other. Remember each of these contour lines represent an elevation. The closer the lines are together, the more dramatic the slope. We can go on for hours on the intricacies of maps and map reading. While writing this article, a flood of information started coming back to me from the old days. I have only touched on a very lengthy subject. If you are new to land navigation and want to know more, I would suggest you start by purchasing a USGS map of a location near you. You can pick them up at nearly all camping and hiking stores. They will also sell some of the tools needed in conjunction with your new map.

Tools for land navigation

A good compass should have at least:

• A clear base plate- To see underneath the compass.
• A rotating bezel, marked with 360 degrees in 2 degree increments.
• Meridian lines- For map use.
• Declination Adjustment and arrow- to correct for the difference between magnetic and true north

A protractor – UTM ruler:

• Your protractor will need to work with 1:24,000 , 1:25,000 and 1:50,000 scale maps
• It should also include a 360 degree compass rose for computing direction.
• The cost is usually less than five dollars, so buying an extra is advisable.

Examples of protractors: If you have or plan to purchase the army protractor keep in mind, it will only work with military scale maps. 1:100,000 – 1:50,000 – 1:25,000. Your USGS maps will have a different scale and coordinate scale part of the protractor will not work. The military protractor is known as GTA 5-2-12. This concludes the first article in our series. I must add that some of the methods and tools described are simply my way of doing business. You may have or develop your own tools and tricks. That is what makes land navigation so exciting. If your way works, do it and be proud. In fact, if you have a better way of doing something, share it with the rest of us. These skills can save you life in an emergency. Keep your GPS handy, but know how to get by without it. Technology is a wonderful tool and it gives us so much convenience and efficiency, but we can also become too dependant on it. In writing this article, evidence of our fast food society is in the very words I type. Technology allowed me to write this article without once consulting a dictionary or thesaurus. Believe me, my spelling and grammar have suffered from not picking up that dictionary. Spell check is the devil. Please check back for the next Find Your Way series of articles where learn how to establish grid coordinates and convert an azimuth. Thanks and see you again soon, H-Minus