what is the shortest distance between two points

WHAT IS THE SHORTEST DISTANCE BETWEEN TWO

POINTS

ODA OBJ

• Straight Line? Not always• Route Planning Considerations

• Rate of travel• Special equipment• Special training• Distance / Time / Energy spent

SPECIAL FORCES QUALIFICATION COURSE

PHASE 1A

BASIC LAND NAVIGATIONSSG. Scott

REASON

To become a Special Forces Soldier, you must be able to navigate cross-country using a map, compass, and protractor, under any conditions.

CLASSROOM CONDUCT

• If you have a question… ask it.• If you feel sleepy, stand up.• No tobacco of any kind (SWC policy).• Can drink.• Wait till break to use bathroom.

MARGINAL INFORMATIONAND

TOPOGRAPHICAL SYMBOLS

OBJECTIVE

• Action: Use marginal information to determine technical specifications about the map and to identify features on the map.

• Condition: Given a 1:50,000 scale military map.• Standard: IAW FM 21-26

REFERENCES

• FM 21-26 MAP READING AND LAND NAVIGATION

REASONS

The instructions for any particular map sheet are located in the upper and lower margins of a map. All military maps are not the same, therefore, these instructions must be read each time a different map sheet is used.

AGENDA

• Locate key marginal information on a military map.• Identify the five different colors used on a map and

state what they represent.

SHEET NAME

• Sheet Name is located in two places. Center of upper margin. Left side of lower margin.

• Usually named for its outstanding cultural or geographic feature.

SHEET NUMBER

• Located in the upper right margin.

• Used as a reference number for that map sheet.

SERIES NAME

• Located in the upper left margin along with the scale.

SERIES NUMBER

• Located in the upper right margin and the lower left margin.

EDITION NUMBER

• Located in the upper margin and the lower left margin.

• Represents the age of the map in relation to other editions.

BAR SCALES

• Located in the center of the lower margin.

• They are rulers.• Used to convert map

distance to ground distance.

ADJOINING SHEET DIAGRAM

• Location varies with scale sizes.

• All military maps contain a diagram which illustrates the adjoining sheets.

INDEX TO BOUNDARIES

• Located in different places on different maps.

• Shows the boundaries which occur within the map area.

GRID NOTE


• Gives information about the grid system used, the interval of grid lines, and the number of digits omitted from grid values.

PROJECTION NOTE

• Located in the lower margin.

• This projection system is the framework of the map.

GRID REFERENCE BOX


• Contains the instructions for composing a grid reference.

VERTICAL DATUM NOTE


• Designates the basis for all vertical control stations, contours, and elevations.

HORIZONTAL DATUM NOTE


• Indicates the basis for all horizontal control stations.

LEGEND

• Located in the lower left margin.

• Illustrates and identifies the topographic symbols used.

DECLINATION DIAGRAM

• Located in the lower margin.

• Indicates the angular relationships of the true, grid, and magnetic north.

USER’S NOTE


• Requests cooperation in correcting errors or omissions.

UNIT IMPRINT


• Identifies the agency that printed the map and the printing date.

CONTOUR INTERVAL


SPECIAL NOTES AND SCALES

• Various locations.• Under certain

conditions, special notes or scales may be added to the marginal information to aid the map reader.

CLASSIFICATION

• Located in the center of the upper and lower margins.

• Certain maps require a note indicating the security classification.

STOCK NUMBER IDENTIFICATION


• All military maps published by the Corps of Engineers have stock identifications.

• Used when requisitioning map supplies.

a

• Where is the sheet name found?• Top center and lower left margin.• Where is the contour interval found?• Center of the lower margin.• Where is the declination diagram found?• Lower margin.• Where is the elevation guide found?• Lower right.

TOPOGRAPHIC SYMBOLS

• Black• Blue• Green• Brown• Red

BLACK

• Used to indicate cultural or man-made features.

• Buildings, roads, spot elevations.

BLUE

• Used to indicate water features.

• Ponds, lakes, rivers, streams, intermittent streams.

GREEN

• Used to indicate vegetation.

• Woods, orchards, vineyards.

BROWN

• Used to indicate surface features.

• Contour lines.

RED

• Used to indicate type or use of man-made features.

• Main roads and built up population areas.

QUESTIONS

OBJECTIVE

• Action: Use marginal information to determine technical specifications about the map and to identify features on the map.

• Condition: Given a 1:50,000 scale military map.• Standard: IAW FM 21-26

AGENDA

• Locate key marginal information on a military map.• Identify the five different colors used on a map and

state what they represent.

• Where is the grid reference box found?• Located in the center of the lower margin.• Where is the contour interval found?• Located in the center of the lower margin.• Where is the declination diagram found?• Located in the lower margin.

REVIEW

REVIEW

• What does black indicate?• Cultural or man-made features. • What does blue indicate?• Water features.• What does green indicate?• Vegetation.• What does brown indicate?• Contour lines.• What does red indicate?• Main roads, built-up areas.

REASONS

• To aid you in finding necessary information on the map sheet.

• To aid you in interpreting symbols and colors on a military map.

MILITARY GRID REFERENCE SYSTEM

OBJECTIVE

• Action: Determine an 8-digit grid coordinate within 10 meters, including the grid zone designator and 100,000 meter square.

• Condition: Given a 1:50,000 military scale map, protractor, pencil, and an unknown point.

• Standard: Within two minutes.

REFERENCE

• FM 21-26- Map Reading and Land Navigation

• Chapter #4• Pages 4-1 through 4-18

REASON

• To become a Special Forces Soldier, you must be able to navigate cross-country using a map, compass, and protractor, under any conditions

AGENDA

• Explain Military Grid Reference System.• Determine Grid Zone Designator.• Determine 100,000 Square Identifier.• Determine a grid coordinate.

GEOGRAPHIC COORDINATES

EQUATOR

N

S

W

PRIME MERIDIAN

E

UNIVERSAL POLAR STEREOGRAPHIC GRID

(UPS)

• Letters: A, B, Y, and Z used.• Each polar area is divided into two zones separated

by the 0-180 meridian.

UPS GRID ZONE DESIGNATOR

w

0

Y Z

A B

180SOUTH POLE

NORTH POLE

E

18 0

0

Z Y

B A

SOUTH POLE

NORTH POLE

E W

• Designed to cover a part of the world between latitude 84`N and latitude 80`S

• Consist of 60 zones

UNIVERSAL TRANSVERSE

MERCATOR (UTM)

Area cover

by UTM grid system

UTM GRID cont.

• Each zone is 6 degrees wide by 8 degrees high and 6 degrees wide by 12 degrees high.

• Zones are numbered from west to east, 1-60, starting at the 180 degree meridian.

• This surface is divided into 20 east-west rows in which 19 rows are 6 degrees wide, 8 degrees high, and 1 row in the extreme north is 6 degrees wide, 12 degrees high.

UTM GRID cont.

• These rows are then lettered from S-N, C through X (letters O and I omitted).

• Any 6 degree by 8 degree, or 6 degree by 12 degree zone can be identified by giving the number and letter of the grid zone and row in which it lies.

• Read right then up.• This combination of zone number and row letter

constitutes the grid zone designation.

UTM GRID ZONE DESIGNATION (17S)

180`

54 55 56 57 58 59 60

180`

174`

168`

162`

C

D

E

X

S

R

1 2 3 4 5 17 53

174`

168

` 162`

RIGHT

UP

16

100,000-METER SQUARE IDENTIFIER

• Between 84 degrees N and 80 degrees S, each zone is covered by 100,000-meter square that is identified by the combination of two alphabetical letters.

UTM GRID ZONE

13 14 15 16 17 N

P

Q

R

S

T

RIGHT

UP

17S18

017

416

816

215

6

8HIGH

6WIDE

P R S

U

R

T

Q

OR 6 WIDE BY 12 HIGH

100,000-METER SQUARE

100,000-METER SQUARE IDENTIFIER cont.

13 14 15 16 17 O

P

Q

R

S

T

RIGHT

UP

17S18

017

416

816

215

6

8HIGH

6WIDE

P R S

U

R

T

Q

PU RU SU

PR RR SR

PT RT ST

PQ RQ SQ

100,000-METER SQUARE IDENTIFIER cont.

• First letter is the column designation.• Second letter is the row designation.• 100,000-meter square identification letters are

located in the grid reference box in marginal information on the map.

GRID ZONE DESIGNATION AND 100,000 METER SQUARE

TU

TM

TL

TK

TJ

XU YP

TN

XM

XN

XL

XK

XJ

YN

YM

YL

PK

YJ

96` 90` 84`

BN

BT

BS

BR

BQ

BP

CN

CT

CS

CR

CQ

CP

GN

GT

GS

GR

GQ

GP

16WPU

IDENTIFICATION (17SPU)

17S

GRID COORDINATE SCALE

• Divides a grid square more accurately.• Designed to plot grid coordinates.• GTA-5-2-12 (1993)

GRID COORDINATE SCALE

• 1:50 scale subdivides the 1,000-meter grid block into 10 major sub-divisions.

• Each equal to 100 meters.

• Each 100 meter block is divided in half, equal to 50 meters.

GRID COORDINATE SCALE cont.

• 1:25,000-scale subdivides the 1,000-meter grid block into 10 major sub-divisions.

• Each equal to 100 meters.

• Each 100-meter block has five graduations, each equal to 20 meters.

READING COORDINATE SCALE

• Place zero index line at lower left corner of grid square.

• Keep scale on lower horizontal grid line.• Slide it right until the point for which the coordinates

are desired, touches the edge of the scale.

READING COORDINATE SCALE cont.

• Ensure that one side of the scale is horizontally aligned with the east-west grid line and that the other side of the scale is vertically parallel with the north-south grid line.

• Read right, then up.

READING COORDINATE SCALE cont.

• The precision of a reference point is shown by the number of digits in the coordinate.

• 4 digit – 1,000 meter square• 6 digit – nearest 100 meter• 8 digit – nearest 10 meter• 10 digit – nearest 1 meter

RECORD COORDINATES IN SEQUENCE

• Grid Zone Designation• 100,000-meter square identification• Complete east and north coordinates• Read right, then up.

RECORD COORDINATE IN SEQUENCE cont.

17S

GRID ZONE DESIGNATION

100,000-M SQUARE

IDENTIFICATION

PU

EIGHT DIGIT GRID

12345678

17SPU 12345678

PRACTICAL EXERCISE

• What is the 8 digit grid for the only building located in grid square 17SPU 23 78?

• 17SPU 2390 7845• What is the 8 digit grid for the church in grid 17SPU

32 84?• 17SPU 3281 8417• What is located at 17SPU 2099 7581?• A school

PRACTICAL EXERCISE cont.

• What is the 8 digit grid for BM 124.2 in grid 17SPU 33 84?

• 17SPU 3315 8420• What is located at 17SPU 3455 7814?• A mine• Where are you standing if you are at grid 17SPU

2660 8149?• A six-way intersection

QUESTIONS

OBJECTIVE

• Action: Determine an 8-digit grid coordinate within 10 meters, including the grid zone designator and 100,000 meter square.

• Condition: Given a 1:50,000 military scale map, protractor, pencil, and an unknown point.

• Standard: Within two minutes.

AGENDA

• Explain Military Grid Reference System.• Determine Grid Zone Designator.• Determine 100,000 Square Identifier.• Determine a grid coordinate.

REVIEW

• The Military Grid Reference System is divided into two parts, what are they?

• UPS and UTM• Where are the GEO coordinates taken from?• Prime Meridian, Equator, and Reference

Lines• The UTM is divided into how many zones?• 60 zones• The UPS is divided into how many zones?• 4 zones

REVIEW cont.

• What letters are used to identify the polar areas?• A, B, Y, and Z

REASON


DIRECTION AND AZIMUTH

OBJECTIVE

• Action: Express an azimuth and back azimuth, convert a grid/magnetic azimuth, state a direction as a unit of angular measurement, determine a grid azimuth, and plot directions.

• Condition: Given a 1:50,000 military scale map, protractor, and pencil.

• Standard: IAW 21-26

REFERENCE

• FM 21-26- Map Reading and Land Navigation

REASON


AGENDA

• Express an azimuth and back azimuth.• Convert a grid and/or magnetic azimuth.• State a direction as a unit of angular measurement.• Determine a grid azimuth.• Plot directions on a military map.

ANGULAR MEASUREMENT

• Degrees• Mils

DEGREES

• Most commonly used unit of measurement.• Sub-divided into minutes and seconds.• 360 degrees in a complete circle.

EXPRESSING DIRECTION

• Start point.• Point of reference.• These two points designate a base line or reference

line.

BASELINES OR REFERENCES

• Magnetic North• Grid North• True North

MAGNETIC NORTH

• Direction to the north magnetic pole.

• Indicated by magnetic instrument.

• Symbolized by a half arrow.

GRID NORTH

• Established by vertical grid lines on a map.

• Symbolized by the letters GN.

TRUE NORTH

• Line from any position on the earth’s surface to the North Pole.

• All lines of Longitude are True North lines.

• Symbolized by a star.

AZIMUTHS

• An azimuth is a horizontal angle measured in a clock-wise manner from a north baseline.

BACK AZIMUTH

• Reverse direction of an azimuth and is comparable to an about-face.

• If the azimuth is more than 180 degrees, subtract 180.

• If the azimuth is less than 180 degrees, add 180.

CONVERT TO BACK AZIMUTHS

• 84 degrees• 172 degrees• 263 degrees• 356 degrees

• 264 degrees• 352 degrees• 83 degrees• 176 degrees

DECLINATION DIAGRAM

• The declination diagram is located on most maps.• Declination is the angular difference between True

North and either Magnetic or Grid North.• The two types of declinations are: Magnetic and

Grid.

GRID-MAGNETIC ANGLE (G-M ANGLE)

• An arc indicated by a dashed line.• Connects the grid and magnetic north prongs or

baselines.• Labeled with size of angle and year it was prepared.

• Where is the G-M Angle located on your map?• What is the G-M Angle on your map?

CONVERTING AZIMUTHS

• Look at your Declination Diagram and read it !

G-M ANGLE

• Convert the following using the G-M Angle on your map.

• 45 degrees MAG• 240 degrees MAG• 359 degrees GRID• 5 degrees Grid

• 37 degrees GRID• 232 degrees GRID• 7 degrees MAG• 13 degrees MAG

PLOTTING DIRECTION

A

C

D

E

B

F

PLOTTING DIRECTIONS cont.

• Place Start Point on the map.• Place End Point on the map.• A line connecting the two points.• Place the center of the protractor over the start

point.• Make sure the protractor is aligned correctly.• Read your grid azimuth.• Convert grid to magnetic.• Move out !

MOST COMMON MISTAKE

• The most common cause of failure while land navigating is improper plotting.

• Plot once and erase it.• Re-read and re-plot, two more times.• When you have the same plot three times, you know

you are correctly plotted.

PRACTICAL EXERCISE

• Start Point: 17SPU 2146 9619• End Point: 17SPU 2003 9391• What are the Grid and Magnetic azimuths?

• Grid – 206 degrees• Magnetic – 214 degrees


Start Point: 17SPU 2630 8556• End Point: 17SPU 2626 8735• What is the azimuth you are going to walk with your

compass?• 007 degrees MAG


• Start Point: 17SPU 3240 9806• End Point: 17SPU 2906 9805• What is the azimuth you are going to walk with your

compass?• 278 degrees MAG

QUESTIONS

OBJECTIVE

• Action: Express an azimuth and back azimuth, convert a grid/magnetic azimuth, state a direction as a unit of angular measurement, determine a grid azimuth, and plot directions.

• Condition: Given a 1:50,000 military scale map, protractor, and pencil.

• Standard: IAW 21-26

AGENDA

• Express an azimuth and back azimuth.• Convert a grid and/or magnetic azimuth.• State a direction as a unit of angular measurement.• Determine a grid azimuth.• Plot directions on a military map.

REVIEW

• WHAT IS THE GM ANGLE ON YOUR MAP• 8 DEGREES• TO CONVERT A MAGNETIC TO A GRID AZIMUTH

WHAT DO YOU DO• SUBTRACT THE GM ANGLE

REASON


INTERSECTION AND RESECTION

OBJECTIVE

• Action: Locate an unknown point within 50 meters.• Condition: Given a 1:50,000 scale military map,

protractor, straightedge, and a pencil.• Standard: IAW 21-26.

REFERENCES

• FM 21-26 MAP READING AND LAND NAVIGATION

REASON


AGENDA

• map and compass method of intersection• straightedge method of intersection• polar plot method• modified resection.

INTERSECTION

• Intersection is the location of an unknown point by successively occupying two points and sighting on the unknown position.

ORIENT THE MAP

• Can be done two ways.• Map method.• Compass method.

MAP METHOD EXAMPLE

COMPASS MEHTOD EXAMPLE

MAP AND COMPASS METHOD OF

INTERSECTION

Once you have oriented the map…• Locate and mark your position on the map.• Find the magnetic azimuth to the unknown point.• Convert to a grid azimuth.• Place the protractor on the map.• Ensure the zero degree indicator is pointed to the

top of the map.

MAP AND COMPASS METHOD OF

INTERSECTION cont.

• Place a tick mark on the azimuth from your location to the unknown point.

• Draw a light line on your map.• Move to another known point and repeat the steps.• The intersecting point of the lines is the unknown

location.

INTERSECTION MAP AND COMPASS EXAMPLE

• 17SPU 4068 8240

A

B

C• Known point A, 45 degree az. MAG

• Known point B, 320 degree az. MAG

• Unknown point.

INTERSECTION MAP AND COMPASS PE

• From: grid 17SPU 15 99BM 199.9

• 142 degrees MAG• From:

grid 17SPU 18 99 Belford church208 degrees MAG

• 17SPU 1785 9708

INTERSECTION MAP AND COMPASS PE cont.

• Grid 17SPU 2995 7990288 degrees MAG

• Grid 17SPU 2750 781626 degrees MAG

• 17SPU 2821 8018

STRAIGHTEDGE METHOD OF INTERSECTION

• The straightedge method is used without a compass to find an unknown point.

• Orient the map by terrain.• Lay the straightedge on the map.• Use your position as a pivot point.• Rotate the straightedge until it lines up with the

unknown point.• Draw a line.• Move to another point and repeat the steps.• Find the eight-digit grid to the intersecting lines.

RESECTION

• The method of locating one’s unknown position on a map.

• Determine the grid azimuth to at least two known points.

RESECTION MAP AND COMPASS METHOD

• Orient the map.• Identify at least two locations on the ground and

mark them on the map.• Take a magnetic azimuth to these locations.• Convert them to grid azimuths.• Change to a back azimuth.• Using the protractor, measure from the known

position back to your location.

RESECTION MAP AND COMPASS METHOD cont.

• Mark this on the map.• Repeat this using a second known location.• The intersection is your location.• Find the eight digit grid.

MAP AND COMPASS RESECTION PE

• From:grid 17SPU 217834look out tower207 degrees MAG

• From:grid 17SPU 2208 8655hill top338 degrees MAG

• 17SPU 2255 8570

STRAIGHTEDGE METHOD OF RESECTION

• Used to identify your location by orienting the map with terrain features, then using the straightedge to find your location.

STRAIGHTEDGE METHOD OF RESECTION cont.

• Orient the map with the terrain.• Locate two known points.• Lay the straightedge on the map.• Use the known point as a pivot point to line up with

your position.• Mark it on your map.• Repeat these steps.• The point where the lines intersect is your location.• Record the eight digit grid coordinate.

MODIFIED RESECTION

• Needs only one known location to find your unknown position.

• You must be located on a linear terrain feature.

MODIFIED RESECTION cont.

• Orient the map.• Locate a known object.• Determine the magnetic azimuth to the known point.• Convert to a grid azimuth.• Convert to a back azimuth.• Plot the azimuth on your map from the known point

to your position.

POLAR PLOT

• Used to locate an unknown point from your location.• You must know the distance to the unknown point.

QUESTIONS

OBJECTIVE

• Action: Locate an unknown point within 50 meters.• Condition: Given a 1:50,000 scale military map,

protractor, straightedge, and a pencil.• Standard: IAW 21-26.

AGENDA

• map and compass method of intersection• straightedge method of intersection• polar plot method• modified resection

REVIEW

• What is a grid azimuth?• What is a magnetic azimuth?• What is a back azimuth?• What is intersection used for?• What is resection used for?• What is the objective of this class?• Why is this important?

REASON


ELEVATIONAND

RELIEF

OBJECTIVE

• Action: Determine the elevation of a point on a map. • Condition: Given a 1:50,000 scale military map, grid

coordinate scale, and protractor.• Standard: IAW FM 21-26

REASON


AGENDA

• Define elevation and relief.• Describe the five methods of depicting relief.• Identify ten terrain features.• Identify four types of slopes.• Measure elevation on a map.• Identify bench marks and spot elevations.

ELEVATION

• To measure elevation and relief, you need a reference point or start point.

• The start point is referred to as the datum plane or mean sea level.

• Mean sea level is the point halfway between high and low tide.

• Elevation is a point on the earth’s surface which is a vertical distance above or below mean sea level.

RELIEF

• The representation of the shapes of hills, valley, streams, and other terrain features on the earth’s surface.

RELIEF DEPICTING METHODS

• Layer tinting• Form lines• Relief shading• Hachures• Contour lines

LAYER TINTING

• Shows relief by color.• Legend depicts

elevation.• Disadvantage of not

knowing the exact elevations.

HighMediumLow

188

142167

85

FORM LINES

• Indicated by dashed lines.

• Are not measured from any datum plane.

• Have no standard elevation and are never labeled with elevations.

RELIEF SHADING AND HACHURES

Relief Shading• Uses a shadow effect, a result of darkening one side

of a terrain feature.• The darker the shading the steeper the slope.• May be used with contour lines.

Hachures• Short, broken lines used to show relief.• May be used with contour lines.• Don’t represent exact elevations.• Primarily used on small scale maps.

CONTOUR LINES

• Most common method of showing relief.• Represents an imaginary line on the ground

connecting points of equal elevation.• The vertical distance between adjacent contour lines

is known as?• The contour interval.

TYPES OF CONTOUR LINES

• Index• Every 5th line, heavier, and numbered.• Intermediate• Fall between index lines, not numbered.• Supplementary• Dashed lines used for sudden elevation changes 1/2

the contour interval.

CONTOUR LINES

• Index

• Intermediate

• Supplementary

• Contour interval is 20 meters

200

100

TERRAIN FEATURES

• Major• Minor

MAJOR TERRAIN FEATURES

• Hill• Saddle• Valley• Ridge• Depression

HILL

• Ground slopes down in all directions.• Contour lines form concentric circles.

SADDLE

• High ground in two opposite directions and lower ground in the other two directions.

VALLEY

• A stream course which consists of reasonably level ground bordered on the sides by higher ground.

RIDGE

• Slopes down in three directions and has high ground in one.

• Contour lines are U or V shaped with the closed end pointing away from the high ground.

DEPRESSION

• A low point on the ground surrounded by higher ground on all sides.

MINOR TERRAIN FEATURES

• Draw• Spur• Cliff• Cut• Fill

DRAW

• Less developed stream course than a valley.• Little or no maneuver room.• Does not need water to be a draw.

SPUR

• A short continuous sloping line of higher ground, normally jutting out from the side of a ridge.

• Often formed by two roughly parallel stream cutting draws down the side of a ridge.

CLIFF

• A vertical or near vertical feature which is an abrupt change in the land.

CUT

• A man-made feature resulting from cutting through high ground to form a level bed for a road or railroad.

FILL

• A man made feature resulting from filling in low ground to form a level roadbed.

FOUR TYPES OF SLOPES

• Uniform Gentle• Uniform Steep• Concave• Convex

UNIFORM GENTLE SLOPE

• Contour lines show a uniformed gentle slope, evenly spaced and wide apart.

100

UNIFORM STEEP

• Contour lines show a uniformed steep slope, evenly spaced and close together.

200

100

CONCAVE

• Contour lines are closer together at the top (steep), and wide apart at the bottom (gentle).

200

100

CONVEX

• Contour lines are wide apart at the top (gentle), and close together at the bottom (steep).

200

100

QUESTIONS

OBJECTIVE

• Action: Determine the elevation of a point on a map. • Condition: Given a 1:50,000 scale military map, grid

coordinate scale, and protractor.• Standard: IAW FM 3-25.26

AGENDA

• Define elevation and relief.• Describe the five methods of depicting relief.• Identify ten terrain features.• Identify four types of slopes.• Measure elevation on a map.• Identify bench marks and spot elevations

TERRAIN FEATURE REVIEW

HILLVALLEYRIDGESADDLEDEPRESSIONDRAWSPURCLIFFCUTFILL

REASON


MEASURING DISTANCE

OBJECTIVE

• Action: Measure distance on a map

• Condition: In a classroom environment, measure straight and curved lined distance from two known points

• Standards: Measure straight and curved line distance from two known points within 50 meter accuracy

REFERENCE

• FM 21-26

REASON


AGENDA

• Graphic (Bar) Scale• Measure Straight Line Distance• Measure Curved Line Distance• Determine Exact Distance• Read Extension Scale

GRAPHIC BAR SCALE

MEASURING STRAIGHT LINE DISTANCE

• Lay a straight-edged piece of paper on the map so that the edge of the paper touches both points and extends past them.

• Make a tick mark on the edge of the paper at each point.

• Measure the distance between the points using the correct unit of measure on the bar scale

MEASURING STRAIGHT LINE DISTANCE

DETERMING STRAIGHT LINE DISTANCE WITH GRAPHIC (BAR) SCALE

MEASURING CURVED DISTANCE

• An 8 digit grid should be used for start and finish point

• Place a tick mark on the paper and map at the beginning point

• Align the edge of the paper along a straight portion and make a tick mark on both map and paper

• Continue to follow the road with the edge of the paper insuring to make tick marks on the map and paper.

MEASURING CURVED LINE DISTANCE

MEASURE CURVED LINE DISTANCE CONT.

DETERMINE DISTANCE

• Use correct unit of measure• Measure the distance between point A

and B• Remember to read from right to left

when using the extension scale.

DETERMINING DISTANCE

DETERMINING EXACT DISTANCE

DETERMINE EXACT DISTANCE USING

EXTENSION SCALE

EXTENSION SCALE CONT.

MEASURING DISTANCE PE

• What is the straight line distance in meters from BM 122.4 in grid 17SPU 2180 to BM 131.2 in grid 17SPU 2479

• 2950 meters• What is the distance from BM 97.3 in

grid 17SPU 2883 to the intersection located at 17SPU 28827945

• 4110 meters

QUESTIONS

OBJECTIVES

• Action: Measure distance on a map

• Condition: In a classroom environment, measure straight and curved lined distance from two known points

• Standards: Measure straight and curved line distance from two known points within 50 meter accuracy

AGENDA

• Graphic (Bar) Scale• Measure Straight Line Distance• Measure Curved Line Distance• Determine Exact Distance• Read Extension Scale

REVIEW

• Which way do you read the extension scale

• Right to Left• What size increments is the extension

scale broken down into• 10 meter increments• Who is the best Land Navigation

instructor in SFQC PH 1A• SFC Lewis

REASON


PACE AND DRIFT COURSE

PACE

• The pace course is broken down by 200, 100, and 50 meters.

• The course is over wooded terrain.• Will be conducted during daylight and evening

hours.

PACE COURSE EXPLAINED

• A pace is considered two steps, usually starting with the left foot.

• If you start with the left foot (and you will), the pace is counted each time the right foot hits the ground.

• Starting at Point # 1, you will go out to the 200 meter mark (striped stake with 200 meters marked on it), turn and go back to the start point, keeping the TOTAL number of paces.

• The total number will then be divided by four to give you your pace count for 100 meters.

• The 100 and 50 meter markers are only there as reference points. (they are marked in the same manner as the 200 meter stake)

DRIFT

• Every soldier drifts left or right moving through the woods.

• It is important to know if you drift left or right.• By knowing which way you drift you know that you

will almost always be to the left or to the right of your point.


1st PLT2nd PLT3rd PLT

PACE AND DRIFT COURSE EXPLAINED

1. When you get to your assigned start point, read the plaque.

2. The plaque will give you a distance in meters, and an azimuth which is a GRID azimuth (convert it).

3. Follow the azimuth using your pace count to go the correct distance.

4. When moving on azimuth, make sure you alternate right and left when going around obstacles.


cont.

5. Continue on azimuth until you get to the end of your pace count and stop.

6. If you have not reached a stake, continue ON AZIMUTH until you get to a stake.

7. If you have passed a row of stakes, take a back azimuth, back to the passed row and stop when you get to a stake.

8. Write down the color and number of the stake, and again, read the plaque and follow the direction.


cont.

9. Once you get to your fourth point (not counting your start point), go back to Point #1 in the lane.


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2

3

4

WHITE LANE EXPLAINED

• KNOW the color lane you left from.• The white lane has blue and red plaques.• If you just came from the red lane, follow the

instructions on the RED plaque.• If you came from the blue lane follow the

instructions on the BLUE plaque.• Any questions?

DRIFT

Correct Distance and Azimuth

Distance and Azimuth Walked

ROADS / BOUNDARIESDUMP

N

what is the shortest distance between two points

Documents

lower left margin

map distance

center of upper margin

military scale map

scale military map

map reading

different map sheet

map area