Mounted Land Navigation - Terrain Association Navigation
12-4. TERRAIN ASSOCIATION NAVIGATION
This is currently the most widely used method of navigation. The navigator plans his route so that he moves from terrain feature to terrain feature. An automobile driver in a city uses this technique as he moves along a street or series of streets, guiding on intersections or features such as stores and parks. Like the driver, the navigator selects routes or "streets" between key points or "intersections." These routes must be capable of sustaining the travel of the vehicle or vehicles, should be relatively direct, and should be easy to follow. In a typical move, the navigator determines his location, determines the location of his objective, notes the position of both on his map, and then selects a route between the two. After examining the terrain, he adjusts the route by the following actions:
a. Consider Tactical Aspects. Avoid skylining, select key terrain for overwatch positions, and select concealed routes.
b. Consider Ease of Movement. Use the easiest possible route and bypass difficult terrain. Remember that a difficult route will be harder to follow, be noisier, cause more wear and tear (and possible recovery problems), and take more time. Tactical surprise is achieved by doing the unexpected. Try to select an axis or corridor instead of a specific route. Make sure you have enough maneuver room for the vehicles.
c. Use Terrain Features as Checkpoints. These must be easily recognizable in the light and weather conditions and at the speed at which you will move. You should be able to find a terrain feature from your location that can be recognized from almost anywhere and used as a guide.
(1) The best checkpoints are linear features that cross your route. Use streams, rivers, hard-top roads, ridges, valleys, and railroads.
(2) The next best checkpoints are elevation changes, such as hills, depressions, spurs, and draws. Look for two contour lines of change. You will not be able to spot less than two lines of change while mounted.
(3) In wooded terrain, try to locate checkpoints at no more than 1,000-meter intervals. In open terrain, you may go to about 5,000 meters.
d. Follow Terrain Features. Movement and navigation along a valley floor or near (not necessarily on) the crest of a ridgeline is easiest.
e. Determine Directions. Break the route down into smaller segments and determine the rough directions that will be followed. You do not need to use the compass; just use the main points of direction (north, northeast, east, and so forth). Before moving, note the location of the sun and locate north. Locate changes of direction, if any, at the checkpoints picked.
f. Determine Distance. Get the total distance to be traveled and the approximate distance between checkpoints. Plan to use the vehicle odometer to keep track of distance traveled. Use the pace count method and keep a record of the distance traveled. When using a pace count, convert from map distance to ground distance by adding the conversion factors of 20 percent for cross-country movement.
g. Make Notes. Mental notes are usually adequate. Try to imagine what the route will be like and remember it.
h. Plan to Avoid Errors. Restudy the route selected. Try to determine where errors are most apt to occur and how to avoid any trouble.
i. Use a Logbook. When the routes have been selected and the navigator has divided the distance to be traveled into legs, prepare a logbook. The logbook is an informal record of the distance and azimuth of each leg, with notes to aid the navigator in following the correct route. The notes list easily identifiable terrain feature at or near the point where the direction of movement changes.