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Orders and annexes are critical components of corps engineer C2. The corps engineer brigade commander exercises functional control over engineer operations within the corps (engineer units supporting maneuver divisions, separate brigades, and cavalry regiments) by including critical instructions in the corps order and the engineer annex. The corps engineer brigade commander also issues a unit order to exercise both functional and unit control over forces committed to corps-level operations. These units are normally task-organized by the corps under the control of the corps engineer brigade commander. Therefore, it is imperative that the corps engineer brigade commander understands how to use the combination of corps and unit orders to convey the plan.

This appendix is divided into two major sections. The first section deals with the corps OPORD, the engineer annex, and the topographic operations annex. This section provides the base format of the corps OPORD, highlighting areas where the corps engineer may have direct input. It also outlines the format and content of the engineer and topographic operations annexes and provides sample overlays. The second section focuses on corps engineer unit orders. It provides a format and content for the corps engineer unit WARNORD and OPORD, including possible annexes, overlays, and FRAGOs.



Figure A-1 is a sample format of the corps OPORD. Paragraphs in which the corps engineer brigade commander may provide engineer input are highlighted.


The engineer annex contains information not included in the base corps order that is critical to the corps engineer plan or required for subordinate engineer planning. It does not include instructions or orders directly to corps engineer units. All instructions or tasks are addressed to maneuver divisions, separate brigades, and cavalry regiments--not supporting corps engineer units. More important, the engineer annex covers critical aspects of the entire engineer plan, not just parts that pertain to engineer units. The engineer annex is not a replacement for a unit order. For example, it does not give subunit orders and service support instructions to engineer units remaining under the corps engineer brigade command; those orders and instructions are contained in the corps engineer brigade order. The engineer annex should meet the following general criteria:

  • Includes critical information derived from the EBA process.
  • Contains all critical information and tasks not covered elsewhere in the order.
  • Does not contain items covered in SOPs unless the mission requires a change to the SOP.
  • Contains information and tasks directed to major subordinate elements of the corps, not supporting engineer units.
  • Contains clear, complete, brief, and timely directives, but avoids qualified directives.
  • Includes only information and instructions that have been fully coordinated with other parts of the OPORD, the corps commander, and the staff.

The engineer annex includes any combination of written instructions, matrices, or overlays necessary to convey the essential details of the engineer plan. The engineer annex provides a standard format for both offensive and defensive operations. This format standardizes the organization of information included as written instructions. The actual content depends on the type of operation and engineer plan. A standardized annex format makes it easier for the engineer staff officer to remember what should be included, as well as for subordinate staff officers to find required information. The format tailors the five-paragraph order to convey critical information.

The engineer annex may also include matrices and overlays, as necessary, to convey the plan. Matrices may be used as part of the body of the annex or as separate appendices. They are used to quickly convey or summarize information not needing explanation, such as logistics allocations, corps obstacle zone priorities and restrictions, or the task summary (execution matrix). Finally, overlays are used to give information or instructions and expedite integration into the overall combined arms plan. At corps level, information shown on overlays may include but is not limited to--

  • All existing and proposed friendly obstacles and control measures (obstacle zones, restrictions, and lanes; directed and reserve obstacles; and corps-level situational obstacles, including associated NAI/TAI).
  • Known and plotted enemy obstacles (must also be on situation template).
  • Logistic locations and routes, as they apply to engineer operations.
  • NBC-contaminated areas.
  • Scatterable mine restrictions.
  • River-crossing locations and restrictions.
  • Proposed thorough decontamination sites.

Figure A-2 is a sample format of a written engineer annex. Figures A-3 through A-5 provide sample matrices and overlays.


The corps prepares a topographic operations annex to all OPORDs. This annex provides the direction needed by subordinate elements of the command to obtain support from topographic units and guidance for the employment of those units. The format for the topographic annex is shown in Figure A-6. Proper preparation of the annex demands detailed identification and definition of all requirements for topographic products and services, whether provided by the DMA or field units. The preparation of the topographic annex is not limited to topographic products, but applies to any products and services in the MC&G field which are required to support the corps OPORD.

The types of products and services needed to carry out unit missions and the quantity and frequency of the support desired, are listed. As a minimum, maps and charts required for operational support must be identified.

To calculate the quantity of maps required for a particular OPORD, plot the geographical areas covered by the unit's areas of operations and interest on copies of appropriate indexes from the DMA or on a theater/JTF map catalog. A small-scale map of the general area may be used to plot and correlate the area to the index. Factors to be considered in setting up areas of operations and interest are given in FM 100-5. Areas of operations are designated by the next higher level of command. An alternative method is listing the stock numbers for all the sheets required. Usually, a combination of both methods is done since each has specific advantages.

The next step is to determine the size and type of units to be employed, since this defines the quantity of products required to support the OPORD. The theater/JTF commanders usually publish supplements to Army Regulation (AR) 115-11 which contain a list of generic units and the quantities of MC&G products each is authorized to order. If a supplement has not been published, the tables found in FM 101-10-1/2, Section IV, Topography, provide the necessary guidance. The quantity per sheet is then the sum of authorization for all subordinate units. The quantity per sheet multiplied by the number of sheets required for the geographical area is the basic load. The term days of supply is meaningless for maps since the speed with which a unit moves through any given area is determined by the mission as influenced by the weather, the terrain, and the enemy situation.

Planning stocks are those maps required by commanders and staffs to plan an anticipated operation. Allowances, most of the time, are no more than 20 percent of the basic load. Command guidance should define whether or not this quantity is authorized in addition to or as part of the basic load.

Operational stocks are those that have been consumed, through loss or destruction, during execution of the OPORD. These stocks must be replaced. Operational stock allowances are usually limited to no more than 20 percent of the basic load.

Overlap must be considered. A simple addition of authorizations for all units under a command is not the total number of maps required for any particular map sheet. To figure this total correctly, look at the geographic area coverage required for each unit at any level, based upon the unit's mission and employment capabilities. Questions such as "Do all divisions in a corps require coverage for the entire corps area?" need to be addressed. Entire coverage may be required for the corps aviation brigade, even though all the maps may not be in use at the same time.


The corps engineer brigade commander uses a unit order to exercise unit control over engineer units remaining under his command. At the outset of an operation, the corps engineer brigade commander uses his order to effect the necessary task organization of engineers in the corps, to assign initial missions, and to establish sustainment integration with the COSCOM and CSGs. Once the task organization is effective and during combat operations, the corps engineer brigade commander directs subsequent unit orders only to those engineers under his command. Orders, missions, and instructions to engineers supporting maneuver divisions, separate brigades, and cavalry regiments in command relationships are included as tasks to the units in the corps order. The exception is the corps engineer unit WARNORD.

The corps engineer brigade commander issues WARNORDs to all engineers in the corps to facilitate parallel planning within engineer units and division, separate brigade, and cavalry regiment engineer staffs. WARNORDs to engineers supporting maneuver units are for planning only and are not executive.


The purpose of the WARNORD is to help engineer staff officers and engineer units initiate planning and preparations for an upcoming operation. The WARNORD is critical to foster parallel planning at the engineer-unit and maneuver-unit levels.

There is no prescribed format for the WARNORD. It may be either written or oral but should include the following information:

  • Heading. WARNORDs must always begin with the words "Warning Order" to ensure recipients understand the information is for use only as a basis for planning and will be followed by orders. The addressees should also be listed in the heading. The corps engineer unit WARNORD should address all engineer units in the corps.
  • Situation. This section includes a brief description of friendly and enemy situations and critical events. It may also include probable missions for the corps and specified or implied tasks, and it may assign tentative tasks for planning only to engineer units.
  • Attachments and Detachments. This section gives tentative and known changes to the task organization. However, it must be clear to engineers supporting maneuver units that changes in task organization are for planning and will not be effective until after an order is received from corps by the supported division, separate brigade, or cavalry regiment.
  • Earliest Time of Move. This section states the earliest possible time that units must be ready to move. For units under the corps engineer brigade commander's command, actual movement times may be given, if known. The earliest time of move is critical to synchronizing sustainment operations to support future missions.
  • Nature and Time of the Operation. This section provides recipients with as much information about the corps plan as possible to foster parallel planning and preparations and to set priorities. Depending on the maturity of the planning process, this section may include a concept of engineer operations or tentative scheme of engineer operations. Orders for preliminary action may also be included, assigning engineer tasks such as tactical/technical reconnaissance, establishing Class IV/V supply points, establishing bridge parks, and moving to linkup points. These orders are normally qualified as be prepared or on order tasks, depending on how the plan is established. Orders to engineers supporting maneuver units are always on order, with execution instructions coming through maneuver headquarters-generated orders.
  • Time and Place of Orders Group. Units under the corps engineer brigade commander's command are told when and where to receive the entire order and who will attend. Units should identify the composition of the orders group in their SOP.
  • Administrative/Logistical Information. This includes instructions and warning information on changes in unit logistics operations and lash-up with maneuver sustainment systems as required by future operations. This information may also direct movement to assembly areas and provide instructions for sustainment after movement.
  • Acknowledgement. An acknowledgment of receipt is always required to make sure it is received by all addressees.


The corps engineer brigade commander issues OPORDs to all engineer units under his command. This OPORD may initially include any engineer unit operating in the corps area as necessary to effect the task organization, assign missions, and establish sustainment responsibility at the outset of an operation. However, once the task organization is effected, all instructions and missions to engineers supporting maneuver units are conveyed in corps orders and are addressed to the maneuver unit commanders. Figure A-7 is an outline of the content of corps engineer unit OPORDs using the standard five-paragraph field order. When the order is an OPLAN instead of an OPORD, assumptions on which the plan is based are included at the end of the Situation paragraph.


The corps engineer brigade commander will frequently need to modify his OPORD through the use of FRAGOs in order to make changes in engineer operations that allow the corps to take advantage of tactical and operational opportunities. The corps engineer brigade commander issues FRAGOs only to engineer units under his command. Changes in instructions to engineers supporting maneuver units in command relationships are conveyed through input into the corps FRAGO. A FRAGO does not have a specified format, but an abbreviated OPORD format is usually used. The key to issuing a FRAGO is to maximize the use of the current OPORD by specifying only information and instructions that have changed. The corps engineer brigade commander can rarely issue FRAGOs to his subordinate commanders face-to-face. He must normally issue FRAGOs over the corps signal net. The corps engineer brigade commander may use the DBC, XO, or a member of his staff to issue the FRAGO in person to subordinate engineer commanders. This ensures that commanders understand the FRAGO and allows graphics to be provided. A FRAGO usually contains the following elements:

  • Changes to Task Organization. Any changes to unit task organizations made necessary by the modification to the order.
  • Situation. Includes a brief statement of current enemy and friendly situations that usually gives the reason for the FRAGO. It may also update subordinates on the current status of corps-level engineer missions.
  • Concept. Gives changes to the scheme of engineer operations and the corresponding changes to subunit tasks. Must also include any changes in the corps or corps engineer brigade commander's intent.
  • Coordinating Instructions. Includes changes to Service Support and Command and Signal paragraphs of the current OPORD made necessary by the change in scheme of engineer operations.

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