LAND NAVIGATION (TC 3-25.26) Flashcards
What is the Field Manual for map reading and land navigation?
FM 3-25.26
What are the basic colors of a map, and what does each color represent?
*Black - Indicates cultural (man-made) features such as buildings and roads, surveyed spot elevations, and all
labels.
*Red-Brown - The colors red and brown are combined to identify cultural features, all relief features, no surveyed spot elevations, and elevation, such as contour lines on red-light readable maps.
*Blue - Identifies hydrography or water features such as lakes, swamps, rivers, and drainage.
*Green - Identifies vegetation with military significance, such as woods, orchards, and vineyards.
*Brown - Identifies all relief features and elevation, such as contours on older edition maps, and cultivated land
on red-light readable maps.
*Red - Classifies cultural features, such as populated areas, main roads, and boundaries, on older maps.
*Other - Occasionally other colors may be used to show special information. These are indicated in the marginal
information as a rule.
What are military symbols?
Figures used to represent types of military organizations, installations, and activities.
Where is the Legend of the map found?
Lower left margin
What are contour lines?
Imaginary lines on the ground connecting equal elevation, they represent high and low ground elevation.
What are 3 types of contour lines?
- Index
- Intermediate
- Supplementary
How many Mils are in one Degree?
17.7 mils
How many Norths are there on a military map?
- True north
- Magnetic north
- Grid north
What shape are the contour lines that indicate a hill?
A hill is shown on a map by contour lines forming concentric circles. The inside of the smallest closed circle is the hilltop.
What shape are the contour lines that indicate a saddle?
A saddle is normally represented as an hourglass.
What shape are the contour lines that indicate a valley?
Contour lines forming a valley are either U-shaped or V-shaped.
What shape are the contour lines that indicate a Ridge?
Contour lines forming a ridge tend to be U-shaped or V-shaped. The closed end of the contour line points away from
high ground.
What are 5 major terrain features found on a map?
- Hill
- Ridge
- Valley
- Saddle
- Depression
What are the 3 minor terrain features found on a military map?
- Draw
- Spur
- Cliff
FM 3-25.26
What are the 2 supplementary terrain features found on a military map?
- Cut
- Fill
FM 3-25.26
What is an azimuth?
A horizontal angle, measured in a clockwise manner from a north base line, expressing direction.
What is vertical distance?
The distance between the highest and lowest points measured.
What is a contour interval?
The vertical distance between adjacent contour lines on a map.
What is the distance between grid lines on a combat map?
1 kilometer or 1000 meters
How many mils are there in a circle?
6400 mils in 360 degrees
Which north is used when using a military map?
Magnetic north when using a compass, and grid north when using the map
What do topographic symbols represent?
Man-made and natural features
In military symbols, what colors are used for a map overlay and what do they represent?
Blue- Friendly forces
Red-Enemy forces
Black- boundaries
Yellow-contaminated area both friendly and enemy
Green- engineer obstacles, both friendly and enemy
How do you figure out a back azimuth?
To obtain a back azimuth from an azimuth, add 180 degrees if the azimuth is 180 degrees or less; subtract 180 degrees
if the azimuth is 180 degrees or more
What is a declination diagram?
Shows the angular relationship between the magnetic north, grid north and true north.
What is a benchmark?
A man-made marker showing points of elevation.
What are parallels of latitude?
Measured distances going north or south of the equator.
What does UTM stand for?
Universal Transverse Mercator
Name two ways to orient a map?
Use a compass and terrain association
What does the term FLOT mean?
Forward Line Of Troops
What are the alternate colors on a map and what do they mean?
Gray- alternate color for brown, Yellow- built up areas, and Pink- political boundaries.
What does the term intersection mean?
Finding the location of an unknown point by sighting two or more known points.
What does the term resection mean?
Resection is the method of locating one’s position on a map by determining the grid azimuth
to at least two well-defined locations that can be pinpointed on the map.
Name 3 field expedient methods of determining direction
The shadow-tip method, the watch method, and the North Star method
What is the name of the map system that the U.S. uses?
UTM
The border line around the edge of the map is called the what?
Neat Line
Name the different slopes found on a map.
- Gentle
- Steep
- Concave
- Convex
What are two methods of measuring an azimuth?
Compass and a protractor
How close will an eight-digit grid get you to your point?
10 meters
How close will a six-digit grid coordinate get you to your point?
100 meters
