071-332-5000 (SL3) - Prepare an Operation Overlay
Standards: Within the specified time, identified the overlay by map reference data, effective date, and purpose. The overlay contained classification markings and downgrading instructions, if applicable and distribution instructions and authentication, if distributed separately. Prepared overlay in accordance with overlay techniques outlined in FM 101?5?1, with boundaries and unit locations plotted to within 50 meters, and tactics and fire support measures to within 25 meters.

Note.  Overlay techniques involve the use of military symbols to portray, in a condensed form, the plans, orders, and information concerning a military operation.

1.   Register the overlay.

a. Orient the overlay material over the map area to the annotated portion and temporarily attach it to the map with the tape.

b. Trace the grid intersections nearest the opposite corners of the overlay and label each with the proper grid coordinates.

2.   Plot new detail. Use colored pencils or markers in standard colors, when available, to plot any detail (FM 101-5-1); otherwise, plot the activity you wish to show with a pen or pencil that makes a lasting mark without cutting the overlay. Use standard military symbols where possible. When the author invents nonstandard symbols, they must be identified on the edge of the overlay.  Show only that detail with which the document is directly concerned.  Standard colors are—

a. Blue or black.  Friendly units, installations, equipment, and activities.

b. Red.  Enemy installations, equipment, and activities.

c. Yellow.  Any areas of chemical, biological or radiological contamination.

d. Green.  Any man-made obstacle.

Note.  If only one color is available, enemy symbols are depicted with double lines.

3.   Mark the overlay classification. The classification of the overlay is dependent upon classification of the order used to prepare the overlay. Mark the top and bottom of the overlay with the classification.

4.   Recognize overlay techniques.

a. Use solid and broken lines.  When the location of a unit or installation or coordinating detail (for example, line of departure or boundary) is in effect and will continue, or is made effective by the order prepared, the appropriate symbol is shown by solid lines. The symbol indicating any proposed or future location, or coordinating detail to become effective later, is shown by broken lines.

b. Boundaries.

(1)  Boundaries show areas of tactical responsibility.  In the offense, these are referred to as zones of action.  In the defense and retrograde, they are referred to as sectors of responsibility.  When described orally, lateral boundaries are described from rear to front in the offense and from front to rear in the defense and retrograde.

(2)  Rear boundaries are used when the area of responsibility for forward units must be precisely defined.  When a rear boundary is not delineated, the rear limit of a unit area of responsibility is determined by visualizing a rear boundary drawn generally parallel to the front, preferably along a natural terrain feature, and connecting at the rearward limit of the unit lateral boundaries.

(3)  If a rear boundary is shown, the size indication along the boundary corresponds to the low unit. Arm or branch is shown when required to prevent confusion (figure 071-332-5000-1).

Figure 071-332-5000-1. Rear Boundary

(4)  Desirably, boundaries are drawn along terrain features easily recognizable on the ground, and are situated, if possible, so the key terrain features, avenues of approach, and river are wholly inclusive of the one unit. They are shown by a solid line if currently in effect or made effective by the order prepared. Their use is based on the techniques and tactics peculiar to the type of tactical operation in which they are used.

(5)  Future or proposed boundaries are shown by a broken line and  labeled to indicate the effective time, if appropriate (figure 071-332-5000-2).

Figure 3-071-332-5000-2. Proposed Boundary

(6)  A symbol is placed on the boundary to show size and designation of the highest units that share the boundary.

(7)  If the units are of unequal size, the symbols of the higher unit are shown and the designation of the lower is given completely to show its size. The boundary between the 52d Infantry Division and the 230th Infantry Brigade (separate) is shown in figure 071-332-5000-3.

Figure 071-332-5000-3. Lateral Boundary

(8)  On overlays or sketches accompanying written or oral orders that specify task organization, unit designation on battalion boundaries indicate the numerical designation. If the battalion is organized into a task force, the letters “TF” precedes the numerical designation. A unit symbol is identified as task force by placing the symbol (||) over the unit size designation (||). Company boundaries are labeled with the appropriate letter unless the company is organized into a team. In the latter case, the boundary is labeled with the abbreviation “TM” and the letter designation or a code name. On other boundaries, only the unit designation needed for clarity is required.  Branch designations may be added when necessary for clarity.  When unequal-size units have a boundary in common, the designation of the smaller unit is spelled out.

c. Axis of advance.

(1)  An axis of advance arrow should extend only as far as this form of control is essential to the overall plan.  Normally, it is shown from the line of departure (LD) to the objective following an avenue of approach.  It indicates that the commander may maneuver his forces and place them freely to either side of the axis to avoid obstacles, engage the enemy, or bypass enemy forces that could not threaten his security or jeopardize the accomplishment of his mission.  The commander ensures that such deviation does not interfere with adjacent units, that his unit remains oriented on the objective, and that the location and size of the bypassed enemy forces are reported to higher headquarters.  Boundaries may be assigned as an additional control measure when using the axis of advance, if the situation so dictates.

(2)  An axis of advance is shown below, identified by a code.  It could be identified by a unit designation (figure 071-332-5000-4).

Figure 071-332-5000-4. Axis of Advance

(3)  To differentiate between a ground axis of advance and an air assault of advance, a twist is placed in the shaft of the open arrow, symbolic of a propeller (figure 071-332-5000-5).

Figure 071-332-5000-5. Air Assault Axis of Advance

d. Direction of attack arrows.  This control measure is used when the commander desires to specify the direction in which the center of mass of a subordinate unit must move in an attack to ensure the accomplishment of a closely coordinated plan of maneuver (for example, in a night attack or counterattack).  A direction of attack arrow should extend from the line of departure to the objective and is not labeled (figure 071-332-5000-6).

Figure 071-332-5000-6. Direction of Attack Arrow

(1)  The arrow should be used only where necessary because it restricts the maneuver of the subordinate unit.

(2)  When a unit is directed to seize successive objectives with its main attack along a certain line, either one arrow extending through the objectives to the final objective or a series of arrows connecting the objectives may be used.

(3)  The double arrowhead is used to distinguish the main attack for the command as a whole (figure 071-332-5000-7).

Figure 071-332-5000-7. Arrowhead Indicating the Main Attack

e. Graphic portrayal of units assigned a security mission.

(1)  To show the general location of a unit with a security mission, arrows generally indicate the terrain over which the unit operates and the farthest extension of its mission (figure 071-332-5000-8).

Figure 071-332-5000-8. Unit With Security Mission

(2)  The primary security mission normally is shown on an operation overlay; however, a secondary or proposed mission is not shown.

f.  Graphic portrayal of supply routes.

(1)  The main supply route (MSR) is the route(s) designated within an area of operations upon which the bulk of traffic flows in support of military operations.  The route is labeled MSR and assigned a code name.

Note.  The term MSR is not used below division level.

(a)   In the defense, the division extends the MSR forward to the brigade trains.  The brigade's supply route (SR) extends from the battalion trains to a point at the rear of the forward company defense sectors.

(b)   In the offense, the proposed SR may be shown forward to the objective or as far as the battalion supply officer (S4) can visualize the combat service support for the operation.  Forward of the LD, it is shown as a broken line.

(2)  The symbols to show the division (offensive action) are shown in figure 071-332-5000-9.

Figure 071-332-5000-9. Division Main Supply Route

(3)  Combat service support facilities are shown on the operation overlay or their location disseminated by the S4, as appropriate.

g. Portrayal of a unit location.

(1)  To show the location of a unit on an overlay, the symbol should be drawn so its center corresponds with the coordinates at which the unit is located (figure 071-332-5000-10).

Figure 071-332-5000-10. Location of a Unit

(2)  To show the location of a training area, observation posts, or logistical activity, the center of the symbol also should correspond with the coordinates at which the element is located.  The illustration shown is the location of an observation post (figure 071-332-5000-11).

Figure 071-332-5000-11. Location of an Observation Post

(3)  The offset technique is used for clarity when space precludes normal placement of symbols.  Offset staffs may be "bent" as required.  The offset staff is dashed for future or proposed locations.  Offset staffs extend vertically from the bottom center of the symbol (except for command posts [CP]). The end of the offset staff indicates exact locations of CPs and aid stations and the center of mass for other units or installations.  The staff for a CP symbol is always on the left edge (figure 071-332-5000-12).

Figure 071-332-5000-12. Offset Technique

(4)  Location of units.

(a)   The locations of attacking units normally are indicated by boundaries (and CP symbols, when the locations of the CPs are known) or by unit symbols.

(b)   The location of the reserve is indicated by an assembly area symbol and by a CP or unit symbol.

(c)   Reserve units of a force assigned defense position or battle position normally are shown by a line enclosing the area occupied or to be occupied—in other words, a "goose egg."  These positions may be numbered or lettered for convenient reference.  An occupied and unoccupied company assembly area (reserve location) is shown in figure 071-332-5000-13.  An occupied and unoccupied reserve company battle position is shown in figure 071-332-5000-14.

Figure 071-332-5000-13. Occupied and Unoccupied Company Assembly Area (Reserve Location)

Figure 071-332-5000-14. Occupied and Unoccupied Reserve Company Battle Position

h. Objective(s).

(1)  Each objective is identified by the abbreviation "OBJ" and a number, letter, or name designation (figure 071-332-5000-15).

Figure 071-332-5000-15. Objective

(2)  An objective assigned by higher headquarters may be given entirely to one subordinate unit or may be divided.  If divided, the objective may be shown graphically as separate objectives and numbered accordingly, or may be divided into two objectives by a boundary line.

i.   Pinch out a unit.

(1)  This type operation is indicated by drawing the boundary across the front of the unit, usually along a well-defined terrain feature such as a stream, ridge, or highway.

(2)  The following example indicates that Company A will be pinched out after seizing OBJ 1; Company B will seize OBJ 2 and continue the attack to seize OBJ 3 (figure 071-332-5000-16).

Figure 071-332-5000-16. Pinching Out a Unit

j.   Defensive battlefield.  The defensive battlefield is organized into the covering force area and the main battle area (MBA) (figure 071-332-5000-17).