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					Map Reading
  & Land
 Navigation
Reference: FM 3-25.26 & CTT Manual
Map Reading
Reference: FM 3-25.26 & CTT Manual
Obtaining Eight Digit Grid Coordinates
 EG03899080……think of it as: EG 0389 9080
 91
                                    X    T
                                         h
                                         e
                                         n
 90
                                         u
                                         p
                    Read Right...
 89


 88
       01      02        03         04
Grid Coordinate Precision
                The more digits in the
                 grid coordinate, the
                  more precise the
                       location!




               Every grid square is 1,000 meters
               square, regardless of the map scale
         Converting Map Distance to
             Ground Distance
                  1:50,000 Map Scale:
1 unit of measure on the map = 50,000 units of measure on the ground
Grid Reference Box
 All sorts of useful information!
              Measuring Curved Lines




 Note the demarcation of the       Pick the right
primary and extension scales!   scale…do you want
                                  meters or miles?
Exceeding the Graphic Scale
 Base Lines & Azimuths

                                               64o




                   244o



You’ll use these   A Back Azimuth is an “about face.”
two most often!    64o azimuth = 244o back azimuth
Declination Diagrams Made Easy!

                       Practical Exercises:
           G-M Angle
             8o E
                         Grid Azimuth= 45o
                        Magnetic Azimuth= ??


                       Magnetic Azimuth = 353o
                         Grid Azimuth = ??


                         Grid Azimuth= 5o
                        Magnetic Azimuth= ??
      There’s converts wherever you
           look….to the West!
To plot a magnetic azimuth on   To use a grid azimuth in the field with
a map, convert it...            a compass, convert it, too…
Your Friend: the Protractor!
                 Accuracy is key!
                       (1) Place the index
                       where the azimuth
                       line cuts a N-S grid
                       line, aligning the base
                       line with the N-S grid
                       line…
                       =or=
                       (2) Count the number
                       of degrees from the 0-
                       and 180- degree mark
                       at the top and bottom
                       of the protractor to
                       the N-S grid line…the
                       two counts should be
                       equal!
    Intersection               Seven Simple Steps:
                               (1) Orient the map.
    Finding an unknown point   (2) Locate and mark your
                               position on the map.
                               (3) Determine the
                               magnetic azimuth to the
                        C      unknown position using
                               the compass.
                               (4) Convert the magnetic
                               azimuth to grid azimuth.
                               (5) Draw a line on the
A                              map from your position
                               on this grid azimuth.
                               (6) Move to a second
                               known point and repeat
                               steps 1-5.
                               (7) The location of the
      B                        unknown position is
                               where the lines cross on
                               the map.
        Resection                   Seven Simple Steps:
                                    (1) Orient the map.
    Finding your unknown location   (2) Identify two or three known
                                    distant locations on the ground
                                    and mark them on the map.
                  C                 (3) Measure the magnetic
                                    azimuth to one of the known
                                    positions from your location
                                    using a compass.
                                    (4) Convert the magnetic azimuth
                                    to a grid azimuth.
B                                   (5) Convert the grid azimuth to a
                                    back azimuth. Using a protractor,
                                    draw a line for the back azimuth
                                    on the map from the known
                                    position back toward your
             A                      unknown position.
                                    (6) Repeat 3-5 for a second
                                    position and a third position, if
                                    desired.
                                    (7) The intersection of the lines is
                                    your location.
Modified
Resection                                 C
  Finding your
unknown location
  along a linear
     feature                                  A
                              B
Six Simple Steps:
(1) Orient the map.
(2) Find a distant point that can be identified on the ground and on the map.
(3) Determine the magnetic azimuth from your location to the distant known point.
(4) Convert the magnetic azimuth to a grid azimuth.
(5) Convert the grid azimuth to a back azimuth. Using a protractor, draw a line for
the back azimuth on the map from the known position back toward your unknown
position.
(6) The location is where the line crosses the linear feature.
Points on Contour Lines




                  Contour Interval
                     20 meters
    Points Between Contour Lines


           X
           d




Contour Interval
   20 meters
Terrain Visualization: Slopes
 TERRAIN
FEATURES
HILL
SADDLE
VALLEY
DEPRESSION
RIDGE
SPUR
DRAW
C
L
I
F
F
C
U
T


    F
    I
    L
    L
  Land
Navigation
 Reference: FM 3-25.26
Lensatic Compass
Compass presets
    Deliberate Offset
& Unplanned Offsets (oops!)



                              180 meters



               1,000 meters
Orienting the Map Using a Compass

                         Map oriented
                         with 11o West
                          declination
Orienting the Map Using Terrain Association
Centerhold technique:
(1) It is faster and easier to use.
(2) It can be used under all conditions
of visibility.
(3) It can be used when navigating
over any type of terrain.
(4) It can be used without putting
down the rifle; however, the rifle must
be slung well back over either
shoulder.
(5) It can be used without removing
eyeglasses.



  Compass-to-cheek technique:
  Most accurate method.
  Used almost exclusively for
  sighting, and it
  is the best technique for this
  purpose.
              Measuring Ground Distance:
                   The Pace Count
• The pace course, regardless of length, must be on similar terrain to that you
  will be walking over.
• Methods to keep track of the distance traveled when using the pace count:
    –   Get yourself a Ranger pace counter
    –   Put a pebble in your pocket every time you have walked 100 meters
    –   Tie knots in a string
    –   Put marks in a notebook
• Adjust pace count for:
    –   Slopes. Your pace lengthens on a downslope and shortens on an upgrade.
    –   Winds. A head wind shortens the pace and a tail wind increases it.
    –   Surfaces. Sand, gravel, mud, snow, etc. tend to shorten the pace.
    –   Elements. Falling snow, rain, or ice cause the pace to be reduced in length.
    –   Clothing. Excess clothing and boots with poor traction affect the pace length.
    –   Visibility. Poor visibility, such as in fog, rain, or darkness, will shorten your pace.
        Your nighttime pace count will be different, so verify it.
    Useful Land Navigation Concepts
• Steering Marks are unique landmarks which
  you can sight on to assist you in staying on the
  correct azimuth.
• Handrails are linear features like roads,
  power lines, ridgelines, or streams that run
  roughly parallel to your direction of travel.
• Catching Features tell you it is time to change
  direction or when you have gone too far.
• Attack Points are known points where area
  navigation ends and point navigation begins.
 Don’t be a Stereotype!

What’s worse: a Lieutenant
or a Lieutenant with a map
        & compass?
   Reference: FM 3-25.26 & CTT Manual

				
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