FM 90-13: River-Crossing Operations

CHAPTER 5 DIVISION DELIBERATE RIVER CROSSING

ADVANCE TO THE RIVER (PHASE I)

Once the division has planned the operation, the first phase is initiated (see Chapter 4). The division will attack to seize nearshore terrain that includes favorable crossing sites and road networks. Normally, the division advances with two brigades abreast and a reserve brigade trailing. The cavalry squadron can provide a forward or flank screen (see Figure 5-3). The DTAC controls the efforts of the lead brigades (see FM 71-100).

Well before the division reaches the river, the cavalry squadron moves ahead of the main body to conduct a reconnaissance of the near shore and predetermined crossing sites. Engineer reconnaissance teams may need to be allocated to the division cavalry squadron to assist in the reconnaissance of crossing sites. If the tactical situation prohibits the cavalry squadron from moving to reconnoiter the crossing sites, one or both of the lead brigades must conduct the reconnaissance. As the division arrives at the river, the lead brigades establish security on the near shore. The lead brigades develop hasty defensive positions to protect the crossing area and cover the crossing sites with direct and indirect fires.

During the advance to the river, the DMAIN coordinates counterfires, close air support (CAS), and support of the division aviation brigade against deep targets. By effectively using these assets, the DMAIN fights the deep battle and isolates the bridgehead.

The DREAR sustains the division's advance. It ensures that key classes of supplies are pre-positioned forward. Priority is shifted to the maintenance of the bridging assets and those of the units supporting the crossing area.

The BTAC controls the fight of the TFs within its brigade. The brigade travels in a formation that is METT-T driven. The brigade seizes objectives that secure the near shore (see Figure 5-4)

Each BMAIN is the crossing-area headquarters. The crossing area is bounded by RLs on the friendly and enemy sides of the river. The RL on the friendly side is usually set 2 to 3 kilometers from the exit bank, out of the range of enemy direct-fire weapons. The RL on the enemy side delineates an area large enough for forces to occupy battalion-sized attack positions. The BMAIN is responsible for controlling units that provide the crossing means, traffic management, and obscuration. Normally, corps assets are task-organized by the division in direct support of the forward brigades to perform these functions. The BMAIN controls these assets. Once the brigade has secured the near shore, MP and engineers mark routes from the staging area to the crossing sites; lay out staging, holding, and call-forward areas; and set up ERPs and TCPs.

Once the near shore is secured, the DTAC becomes the crossing-force headquarters responsible for coordinating the close operations of the committed brigades within the bridgehead and crossing area. The bridgehead is the area on the far shore that is required to provide space and time for the buildup of combat power to continue offensive combat operations. The crossing area is the area, bounded on either side of the river by RLs, in which units move on predetermined routes and use the time tables that are specified in the division's order.

The DTAC coordinates the efforts of the lead brigades as they prepare to assault across the river.

ASSAULT ACROSS THE RIVER

(PHASE II) The DMAIN continues to control deep-fire assets to isolate the bridgehead. As units advance, deep fires shift to subsequent targets. The division coordinates with the corps for SHORAD and HIMAD coverage to protect the bridgehead from enemy air interdiction. The corps normally provides Patriot and Hawk support. The division AD battalion provides local AD coverage. The river creates lucrative targets at relatively fixed locations that are easily targeted by enemy air. Therefore, approaches; holding, staging, and call-forward areas; and crossing sites along the river are the highest priority for AD during the crossing. AD units occupy positions to engage aircraft with massed fires before the aircraft can reach weapons release points (RPs).

The DTAC coordinates the actions of the brigades conducting the assault across the river (see Figure 5-5). The crossing sites are chosen because of available concealment, a good route system, and sufficient space for AAs on the near shore. These sites also have defensible terrain on the far shore of the river to provide a secure base for continuing the operation.

The DREAR begins to push packages of Class IV and V supplies to support the hasty defense to secure the bridgehead line.

The BTACs control their own respective assault-crossing elements, which normally consist of dismounted infantry. A corps combat engineer company, operating assault boats (RB15s) from the corps bridge companies, transports the dismounted soldiers of the assault force to the far shore. The dismounted element crosses the river and secures terrain for the reinforcing armored vehicles. The assault across the river can also be an air-assault operation. The dismounted assault forces are supported by the tanks and infantry fighting vehicles from their TF and by other combat units in support-by-fire positions. Heavy rafts are prepared to transport tanks and infantry fighting vehicles to the far shore for reinforcing the dismounted infantry. M9 ACEs/dozers are transported to prepare the far-shore exit sites. Rapid reinforcement of dismounted assault forces with armored vehicles may be so critical, based on the METT-T, that it justifies using any expedient method to get the first few armored vehicles across. This includes winching, towing, or pushing the first ones across normally unsuitable places while engineers improve entry and exit points for the rest.

Each BMAIN controls smoke to obscure crossing sites on the river. When employed, the smoke blanket covers several kilometers of the river and river approaches to conceal the actual crossing locations, but not as to obscure the bridge crewmens' vision. The crossing-area headquarters uses smoke generators, smoke pots, and smoke munitions from the division and corps. The BMAIN controls the use of MP and corps engineer units to establish nearshore waiting areas, mark routes to the crossing sites, and begin constructing heavy rafts and/or bridges.

The intent of this phase is to rapidly place combat power on the far shore to eliminate the enemy's direct fire onto the crossing sites and secure terrain for attack positions. Brigades normally establish limits of advance (LOAs) and fire-support coordination lines (FSCLs) for the dismounted TFs conducting the assault. These lines establish an LOA that encompasses the far-shore objective. Enemy indirect fire into the crossing area will probably continue; however, each crossing site within the crossing area must be isolated from direct fire to enable the construction and operation of rafts. These rafts will then be used to transport armored vehicles for rapid reinforcement of the dismounted infantry TF. Within the crossing area, secured attack positions allow units to form into combat formations before continuing the attack.

Commanders may consider immediate construction of a bridge during this phase without ever conducting rafting operations. The advantage is that combat power can be massed on the far shore at a much faster rate. The risk that the commander takes in making this decision is that a large amount of bridging assets is exposed to enemy fire before the elimination of enemy indirect fires on the crossing area.

ADVANCE FROM THE EXIT BANK

(PHASE III) The division continues its attempt to secure the bridgehead line by attacking to seize and secure exit-bank and intermediate objectives. The intent is to eliminate direct and observed indirect fires from the crossing area (see Figure 5-6)

The division commander selects exit-bank and intermediate objectives based on METT-T. The river splits the attacking force, limiting massed direct fires beyond the exit bank. Therefore, these objectives are usually smaller and not as far from the attack positions as the objectives used in other offensive operations.

Once the exit banks are secured, the division cavalry squadron crosses either by swimming or rafting their cavalry fighting vehicles. They then conduct normal screening operations for the division as the armored reinforcements are crossing the river and preparing to advance from the exit bank.

The DTAC controls the coordinated attack of the lead brigades and the cavalry squadron to seize exit-bank and intermediate objectives. The DMAIN controls deep fires that aviation, artillery, and CAS provide to block enemy counterattacks into the bridgehead as requested by the DTAC.

The DREAR prepares to push packages of Class III and V supplies that will support the attack out of the bridgehead. They also begin to push Class IV and V supplies for the hasty defense during the last phase of the river-crossing operation.

The BMAINs control the movement of their follow-on TFs from the staging areas across the river to their attack positions on the far shore. They control the upgrade of crossing sites from assaults boats (RB15s) to heavy rafts and/or bridging to ensure that the force buildup can support the advance from the exit bank to intermediate objectives. MP and, if available, corps combat engineers assist in movement control through the crossing area.

During this phase, limited two-way traffic begins to return disabled equipment and casualties.

The BTAC controls the movement out of the attack positions to exit-bank and intermediate objectives. Exit-bank objectives are those positions that, when seized, eliminate the enemy's ability to use direct-fire weapons on the crossing area. Intermediate objectives are those positions from which the enemy can provide observation for indirect-fire weapons. This enables the expansion of SHORAD coverage, allowing more time to engage aircraft in air avenues of approach on the far shore (see Figure 5-7).

The TF that conducted the dismounted assault across the river continues to cross armored vehicles and remount their dismounted soldiers in preparation for continued offensive operations.

The brigade commanders establish the order of raft loads based on the division's crossing priorities. Bridge companies run heavy raft sites and begin to construct ribbon bridges. MP mark routes and control holding areas on the far shore to ensure rapid transit within the crossing area.

SECURE THE BRIDGEHEAD LINE

(PHASE IV) The bridgehead must be defendable and large enough to accommodate forces that will break out to continue offensive combat operations. The lead brigades attack to secure the final objectives within the bridgehead to prevent the enemy from successfully counterattacking against forces within the bridgehead line by rapidly building enough combat power to establish a hasty defense in the sector. The cavalry squadron conducts a screen mission. The lead brigades maintain continuous far-shore security to prevent bypassed enemy elements from infiltrating back to the river and disrupting activities at the crossing sites (see Figure 5-8).

The DTAC controls the lead brigades and the cavalry squadron as they secure the bridgehead objectives (see Figure 5-8) and prepare to move the reserve brigade or other corps forces (breakout forces) into attack positions within the bridgehead. Once the bridgehead objectives are secured, the lead brigades establish a hasty defense in sector.

The DREAR begins to push forward Class III and V supplies that are needed for the attack out of the bridgehead.

The BMAIN continues to upgrade and monitor the crossing sites and control the movement of forces through the crossing area. The far-bank RL, defining the crossing area, is moved just past the intermediate objectives (see Figure 5-8) to provide space for the breakout forces. Once the bridgehead line is secure, the DTAC controls the movement of the breakout forces through the crossing area to attack positions within the bridgehead. During this phase, specific bridges and/or rafts are designed for full-time return traffic. This ensures that resupply and the evacuation of wounded soldiers and disabled equipment occur.

The DMAIN controls the aviation, artillery, and available CAS sorties to screen the flanks and interdict enemy counterattacks. Deep operations play a key role in the bridgehead defense by targeting enemy formations as they move to counterattack. They also eliminate effective artillery fire within range of the bridgehead and destroy other enemy artillery forces moving up to the fight.

The lead brigade elements that secure the bridgehead line must control the avenues of approach into the bridgehead and be large enough to defeat counterattacks. After the bridgehead is secure, the division commander commits the breakout force to attack position within the bridgehead. The bridgehead needs enough space (20 to 30 kilometers deep) to accommodate both the lead brigades and the breakout force with their combat service support (CSS). The bridgehead line must also be deep enough to employ AD systems against hostile aircraft before they reach weapons RPs to attack crossing sites.