"Where are we?"|
© 2006 RogueTurtle.com
Be ready with a confident reply.
Dreaded words to a male family member. "Why don't you stop and get directions?" Another one to put a chill into the hearts of red-blooded men who pride themselves on their uncanny ability to go anywhere in the world...from memory.
"Are you SURE you know where we are?" Only one possible answer to this question… "Yes".
So, I'm not writing this article for my male readers, but for the female members who "just want to check up on how you're doing."
YOU HAVE TO START SOMEWHERE: The MAP
An abstract representation of the physical features of a portion of the Earth's surface graphically displayed on a planar surface. Maps display signs, symbols, and spatial relationships among the features. They typically emphasize, generalize, and omit certain features from the display to meet design objectives (e.g., railroad features might be included in a transportation map but omitted from a highway map).
We are all aware of road maps, city maps, theme park maps, and those things that you can never fold up a second time. These maps are for general use in going from point A to point B, without getting lost. Most often, the roads are marked with highway numbers, distances between points on the map, and hundreds of other items depending on who made the map. A Texaco map will have all the Texaco stations highlighted so you can stop at any of their stations. They are usually made of paper that turns to Jell-O as soon as it gets wet. After about three attempts to fold it and refold it, most tear along the fold lines, so you now have two maps.
The problem with land navigation with a gas station road map is that it usually doesn't have all the information that you need if you are walking cross country. It may show a huge mountain range as a slightly darker color than sea level, with only a few specified peaks showing how high they are. Granted, maps have their uses and are better than nothing at all. But, there are better documents to use.
A map especially prepared for navigation. Land: A map that includes terrain elevations and all features available at the time of the chart printing. Sea: A map exhibiting features associated with a body of water such as depth, hazards, buoys, and bottom sediments; a map for the use of navigators.
Charts are almost always more accurate than maps. Cartographers (people who make charts) now are using satellite imagery to update their charts. Map makers may take local on-the-ground survey data to make their maps. But most maps are concerned with driving our nations highways - not how to get from A to B by foot. Charts are usually made of a better quality paper or have plastic laminates to prevent moisture damage. Charts are also a lot more expensive.
Charts may have cross-referenced grids on them for special navigational problems. For example, in polar regions, North is "DOWN". At the North (Magnetic) Pole, every direction is South. Other systems of navigation (besides the compass) have to be used to navigate in those regions.
Charts will have contour lines for most land navigation purposes. A contour line shows you how high the next hill is, and the next one after that. By closely examining these contour lines, you can pick out the best route of travel for your group. Or, it can show you the best place to set up an ambush. The situation dictates the need.
Maps are great for interstate driving. AAA makes a living selling their page-by-page routes from A to B. But, don't try to walk anywhere other than the highways, the land structure all looks the same...white.
Later this year, I will go into agonizing detail on the use of charts. If you own a boat, you are probably already familiar with nautical charts. Either that, or you run aground a lot. On the West Coast of Florida, there are two kinds of boaters. Those who have run aground (already), or those who are about to. Shallow channels fill with sand after every hurricane, and we have a lot of those. Even the most accurate nautical chart in the world cannot point out a huge tanker that sank in the channel yesterday. Just north of where I live, one of the twin-span bridges that crossed Tampa Bay was hit by a large freighter that had lost power in a storm. The entire center section of one span just "disappeared". Several vehicles, including one semi-tractor trailer, went over the edge without knowing what happened. The road was just "gone". It took almost a year before the nautical charts caught up to this disaster and marked the channel as blocked. The bridge debris kept boat repair business in the green for years afterward. The "locals" knew about the blockage...Snow Birds didn't. The chart makers did publish an update as soon as it was known, but unless you actually read it - and updated you chart by hand - you never knew it happened.
On land, developers can build faster than map makers or cartographers can keep up. But, hills and rivers, and terrain elevations seldom (if ever) change. Natural disasters such as the Mt. St. Helens volcano blowing its top, are the very noticeable exceptions.
Chart information, backed up with local area road maps, can give you a total and complete overview of the area you are in.
I was an aviator in the U.S. Air Force and I retired with the aeronautical rating of Master Navigator. I have used many, many types of maps and charts. With the satellites available today, the charts now are better and more accurate than they have ever been. They are also more expensive. You don't have to opt for global chart coverage...or even US-wide coverage. Just the area you will be trekking in. But, if you think its possible that you might roam farther afield, get all the charts that surround your area. It never hurts to plan ahead. Caution: Aviation charts usually do NOT have highway or street numbers.
CHARTS ALONE ARE NOT ENOUGH
Just because you know where you are NOW, doesn't mean you will know where you will be 6 hours from now. In order to properly use a chart (or a map), you need something to help guide you in the correct direction. Of course, I'm talking about the compass.
There are as many compass manufacturers out there as there are shoe manufacturers. There are many different styles and costs vary wildly. Let's explore the tip of the iceberg.
A GOOD COMPASS|
Without road signs, street signs, buildings and other people, finding your way around can be pretty scary. It takes a good map and a good compass to find out where you are...and which way to go to get wherever you want. The basic compass is the heart-blood of the tools that should be on your person all the time. Everyone in your party should have a good compass. I own about 12 of the things.
The following is just a brief overview of the different types of compasses that are available to purchase. Don't wait until the last minute and have to settle for a junk compass. Get yours now.
Boxed compasses come in a number of sizes and shapes, and above all, cost. The box protects the compass from damage while traveling, but in the woods the box can be a pain in the neck to unpack, set up, and repack. While these are probably the best in terms of accuracy, they lose a lot in ease of use.
If you were going to be using a boat, I would recommend one of these (waterproof, of course). But if you're hiking in the woods, find another style.
This little liquid filled, luminous sportsman's survival compass clips onto your own watch band. It sells for about $7.00. Very handy for general directions, but not very accurate beyond the N, S, E, and W headings. It's better than nothing.
For more accuracy, we need something between these first two examples.
The Lensatic Compass is my first choice for land navigation compasses. Primarily, because this is the one I learned on first, back in Wisconsin. The gimbaled compass rose can be read in the dark. Using the top cover slot and the magnifying flip-up eye piece, you can sight in on any object and get a very accurate reading from the compass. A lanyard (not included) can be used to hang it around your neck. The metal case (brass, in this example) protects the delicate compass from damage when in use.
If you are going to have more than one compass in your group, one of them should be a Lensatic Compass. Prices range from less than $10.00 up to over $70.00 for brass models.
Woodman's Field Compass:
Set in on the map, orient the map and the compass to north, and read the map right through the clear plastic compass. It has a magnifying lens built in, so it can also be used for starting fires on a sunny day. This model comes with its own lanyard to wear the compass, but has a snap-lock so you can easily take it off to use it.
This is my number 2 favorite compass, and I have several around my camping stuff. My step-daughter has one of her own. My daughter has probably lost hers. Cost: $15.00
The Brunton Transit:
The premiere compass for the sport of orienteering. This little jewel has all the refinements (and subsequent costs) of a precision instrument. This tool is very accurate and is probably great when you are competing for a championship, but is much too expensive for knock-around daily use in the woods. I would worry too much about losing it to enjoy its accuracy.
Cost: Over $100.00 each.
For the Tech-no-nuts: Sure, there has to be a whole line of compasses that will give digital or analog readouts, have built in storage for phone numbers and recipes, and comes complete with beautiful women. They work fine as long as the batteries last. When the batteries die, it's a very expensive rock. It does the same thing as all the compasses above do (except store recipes), so why go to the expense of having a piece of survival gear you know will stop working? Cost: Sky's the limit.
Nice for weekends and vacations, sure! Good for survival navigation - NO!
PROPER PRIOR PLANNING PREVENTS POOR PERFORMANCE: No batteries? Tough.
Summary: One compass per person, kids included. Buy your own, but keep them functional. Practice using them.
Global Positioning System (Techno-Toys)
The GPS system is a satellite-based system that provides the accuracy of space technology and the portability of a pocket-sized calculator. Devised originally for the military, this system uses space satellites in geo-synchronous orbit over the earth to determine (using trigonometry) where you are. Thank goodness the machine does the math because I can't do it. Anyway, the handheld GPS receiver will "lock on" to one or more satellites. The receiver uses the signals from the satellites to determine your exact latitude and longitude on earth. The more satellites it locks on to, the more accurate your position is.
Marine Systems: Many GPS systems have been developed for the coastal and lakes areas of the world. Since the GPS receiver is basically a mini-computer, the programs can include: The coastline for the area you are in; the water depth in the area; the channel marker names, numbers, or positions; hazards to navigation; islands and bridges; and many, many more items important for safe nautical navigation.
Land Systems: Since the GPS was developed for the military, many of the functions of GPS for military use are not available in civilian systems. However, many companies have developed local area programs for the GPS receivers for land use. I don't think they are available for everywhere, but they are working on it. Newer high-end vehicles now have on-board systems for use in major cities of the world, as well as driving from city to city. All of these systems use the same GPS satellites as the hand-held types.
Limitations: The GPS hand-held receiver has to have line-of-sight radio signals to all the satellites. That means that you can't be underground, indoors in a metal building, or behind a mountain. They all require batteries to operate, a major problem during extended outdoor stays. Older models take a long time to "initialize", that is, start-up time is delayed while the GPS receiver computes and updates your position as it locks on to satellites one at a time. However, once it locks on, it usually stays on and tracks the satellites as you move around. If you turn it off (to save batteries) it has to go through the whole process all over again. It is not unusual for a GPS receiver to lock on to five or more satellites at one time.
Advantages: The GPS is very accurate and you can count on your position on earth being accurate up to within 10 meters from where it says you are. Some land systems have pre-programmed contour lines, highways, rivers, etc., in the programs to make land navigation much easier. In those areas not covered by pre-programmed maps, the latitude and longitude readouts are still accurate and valid. You just have to plot them on a map yourself. In the mountains, the GPS can also tell you how high you are (altitude).
While there are numerous manufacturers of GPS receivers, I've only selected two typical Magellan types:
SPORT TRAK COLOR (North America)
Accuracy to within 10 meters. High contrast, full color easily displays location, heading and route. Built-in mapping. Additional 22 MB memory for mapping North America. Optional hardware for 3-axis navigational accuracy no matter how you hold the receiver. Built in barometer for weather observations. Compass is accurate no matter how you hold it. Can track up to 12 satellites at one time. Built-in mapping database of highways, major roads, parks, waterways, airports, cities, and navigational aids. Expandable programs available for regional areas. Stores routes and track-points. Rugged construction, weight of only 6.8 oz.
2 AA-batteries for 14 hours of operation.
Rugged and cost-efficient system designed with a built-in 2 MB mapping database of North America and unlimited expandability. Accuracy by tracking up to 12 satellites, within 3 meters or better. Very similar to the Sport Trak, above, downloading street level maps is possible on an optional Magellan SD memory card. Seven customizable graphic navigation displays show a map, compass, speedometer, and text readouts of heading, bearing, speed direction, ETA and more. Built-in with 12 coordinate systems and 76 datums including Latitude/Longitude, Universal Transverse Mercator, and Military Grid Reference System. Stores 20 routes, 500 waypoints, and 2000 track-points. Shows you direction even when standing still. Sunrise/sunset tables, fish and game calculator. Rugged construction, waterproof (it floats).
PRICES: Vary depending on where you buy them. If you need one, pay the money and shut up.
Best use: Set starting point, waypoints and destination. Update twice a day, shutting down otherwise. Cross check route on paper maps, using manual compass for directions while traveling.
YOU DID NOTICE THAT BOTH THESE GPS TOYS REQUIRE BATTERIES? DON'T RELY 100% ON THESE BECAUSE WHEN YOUR BATTERIES DIE, YOU ARE OUT OF BUSINESS.
FIELD-EXPEDIENT DIRECTION FINDING|
The Watch Method
The "Watch Method" uses a common or analog watch - one that has hands. The direction will be true if you are using true local time, without changes for daylight savings time. The further you are away from the equator, the more accurate this method will be.
In the NORTHERN HEMISPHERE, hold the watch horizontal and point the HOUR HAND at the sun. BISECT the angle between the hour hand and the 12 o'clock mark on the watch. The NORTH-SOUTH LINE passes through the center of the watch, through the bisected angle, and points to NORTH. The opposite end of the line points to SOUTH.
If there is any doubt as to which end of the line is north, remember that the sun rises in the east, and sets in the west; and is due south at noon. The sun remains in the east before noon, and will be in the west after noon.
NOTE: If your watch is set on daylight savings time, don't re-set the watch for fear of losing the accurate local time. Instead, use the midway point between the hour hand and 1 o'clock to determine the NORTH-SOUTH LINE.
If you are in the SOUTHERN HEMISPHERE, point the watch's 12 o'clock mark at the sun and use the midpoint halfway between the 12 o'clock position and the hour hand as your NORTH-SOUTH LINE.
Contrary to popular opinion, MOSS does not always grow on the North Side of trees. Moss, like any plant, grows best facing the sun. Unfortunately, in a heavily wooded area, sunlight is hard to come by around the base of a tree. Generally, moss will grow more heavily facing SOUTH, or the direction of the best available light.
USING THE STARS|
The major constellations to learn are the Ursa Major, a.k.a. Big Dipper or the Plow, and Cassiopeia (the Bow of the Archer). They are always visible on a clear night. Use them to Locate POLARIS, the NORTH STAR. The North Star is actually part of the handle of the Little Dipper, which is sometimes confused with the Big Dipper. Prevent confusion by using both the Big Dipper and Cassiopeia together.
The Big Dipper and Cassiopeia are always opposite each other and rotate counter-clockwise around Polaris, with Polaris in the center of the rotation. The Big Dipper is a seven-star constellation in the shape of a dipper. The two stars in the lip of the dipper are the "pointer stars" because they always point to the North Star.
Mentally draw a line from the two stars as shown in the above diagram and extend the line about 5 times the distance between the pointer stars. You will find Polaris on this line. Cassiopeia has 5 stars in a "W" shape. Polaris is straight out from the center star of the "W".
USING THE STARS|
There is no equivalent star to Polaris in the Southern Hemisphere, but there is a bright 4-star constellation known as the SOUTHERN CROSS. These four bright stars form a tilted cross with the long axis of the tilted cross pointing downward at an angle.
Mentally compute a distance 5 times the distance from the two stars that form the long axis of the Southern Cross. This imaginary point is SOUTH. Once you have computed the location of South, drop your eyes straight down to earth and pick out a landmark to use for navigation purposes.
As you walk, keep the South Landmark that you have selected in sight. For example, if you have to travel to the East, the South Landmark should be off your right shoulder. In the daytime, use stakes that you drive in the ground to point to "South" and navigate from landmarks based on the stake layout.