b. Map Overlays. Map overlays show the routes of travel, unit
movements, and decision graphics for both enemy and friendly forces
using standard military symbols (FM 10151). You can prepare a map
overlay as a onecolor or multicolor presentation.
(1) Onecolor presentation. When preparing the overlay as a one
color presentation, use solid single lines to construct the symbols for
the friendly forces and solid double lines to construct the symbols for
enemy forces. Additionally, all symbols representing enemy equipment,
ground positions, and activities have the abbreviation "EN" shown in
(2) Multicolor presentation. When preparing the overlay as a
multicolor presentation and showing the symbols representing friendly
units, posts, installations, equipment, and ground activities, use blue
or black for symbols identifying friendly forces and red for enemy
Use yellow to show both friendly and enemy chemical or radiological
areas and enemy biological areas and use green to indicate friendly and
enemy manmade obstacles. To help show who made or created any of the
areas, place the abbreviation EN in the enemy forces symbols. If you
use any other color in your presentation, ensure that a legend explains
the color's use.
(3) Preparing a map overlay. To prepare the overlay, tape the
required map or map section to the drawing surface and attach a sheet of
tracing paper over the area for which you must prepare the overlay.
Then trace and label two grid registration marks on the tracing paper,
one in the upper lefthand corner and the other in the lower righthand
corner (figure 229). All map overlays must have two grid registration
marks, each showing horizontal and vertical grid identifiers.
When you have the tracing paper correctly orientated and marked, place
the security classification at the top and bottom center of the overlay,
and plot the data from the VI work order or information sheet provided,
using standard military symbols. Using a coordinate scale and
protractor to plot the symbols ensures the symbols are located
accurately on the overlay.
This concludes lesson 2 of the subcourse. Before proceeding to the
examination, complete the practice exercise that follows this lesson.
When you have completed the practice exercises and have a thorough
understanding of the lesson, then complete the examination for the