Crossing Rivers and Bridging Gaps in Doctrine: Experiences from Remagen Ready 24-01

Winter-Spring 2024 Crossing Rivers and Bridging Gaps in Doctrine: Experiences from Remagen Ready 24-01 by MAJ Korey Gaines and MAJ John Kearby A lone Joint Light Tactical Vehicle (JLTV) idles softly under a camouflage net, nestled into the scrub oak underbrush. The humvee, guided by the JLTV’s Joint Battle Command-Platform signature, slides into place – door to door with the JLTV. Passenger side doors open … and the crossing area headquarters is born. The 2nd Battalion, 8th Cavalry Regiment (Stallion) and the 20th Engineer Battal ion operations officers exchange a greeting and get down to the thorny business of sequencing and rafting the Stallion Task Force across Cowhouse Creek. The 1st Brigade, 1st Cavalry Divi sion and the 36th Engineer Brigade re cently participated in Remagen Ready 24-01, a division-level gap crossing ex ercise at Fort Cavazos, TX. The follow ing highlights the advances in thinking gained during that event… Recent large-scale wet gap crossing ex ercises, and the logical implications of a future operational environment on those operations, suggest that Figure 1. 1/1CD rafting their Armored Cavalry Troop during Remagen Ready 24-01 – An M1 Abrams tank rides on a 43rd Multi-Role Bridge Company (MRBC) raft under the direction of 2-8 Cavalry and the 20th Engineer Battalion. Rafting op erations took place after 2-5 Cavalry had seized far-side objectives via air and boat assaults. (U.S. Army photo by MAJ Garrison Spencer, U.S. Army Corps of Engineers (USACE) Public Affairs Officer) significant gaps exist in our published doctrine. The current body of knowl edge reflected in Army Techniques Publication (ATP) 3-90.4, Combined Arms Mobility, specifically Chapters 4 and 5 – “Gap Crossing in Support of Maneuver and Deliberate Gap Cross ing,” either lack sufficient detail to be relevant at the brigade and battalion level or present conflicts with what we know to be true about Field Manual (FM) 3.0, Operations, styled largescale combat operations (LSCO) in the age of convergence. It is apparent that the gap crossing principles – specifically those related to planning, reconnaissance, and com mand and control, require significant overhauling and improved depth to provide value to our formations in both the current and future operation al environments. The first area to address in the doc trine relates to the planning of wet gap crossing operations and the echelon at which detailed planning must occur. Much of the discussion revolves around operations at the division level – but significant and specific effort is required at the brigade and battalion level to support and enable the detail for division. The gap crossing funda mentals of extensive preparation, flex ible planning, and traffic management all reflect clear truths, but they omit the literal requirement of parallel plan ning and battlefield development at the brigade and battalion level. The doctrine does not go far enough in describing what a brigade or battalion staff should do to achieve those prin ciples or what their roles might be. The following represents our recommenda tions. Maneuver and support force brigade and battalion staffs need to develop basic working relationships and pro vide each other with capabilities brief ings, discuss how they each visualize and understand gap crossing opera tions, and conduct joint academic ses sions to educate each other on the specifics of their functions. Leading up to Remagen Ready 24-01 – 1st Armored

Winter-Spring 2024 Brigade Combat Team (ABCT) hosted Wet Gap Crossing Leader Professional Development sessions, conducted nu merous terrain walks with command ers at various echelons, and arranged the participation of support forces in staff training exercises. The ATP suggests that support forces “must link up”1 – but we believe that significantly more early interaction is necessary as described above. The planning for a wet gap crossing re quires flexibility be built into the oper ation, but it also requires tremendous depth and detail that can only be de veloped at lower echelons. The litera ture suggests worthy features of a flex ible gap crossing plan – such as alter nate crossing sites and holding equip ment in reserve – but critical details Figure 2. Multi-Role Bridge Company Raft Construction – The 43rd and 74th MRBCs assemble 7-Float rafts capable of ferrying multiple armored vehicles across Belton Lake. Early trips are conducted using a horizontal rafting style (pictured above), while subsequent iterations employ longitudinal rafting where the Bridge Erection Boats are positioned on both sides of the raft. (U.S. Army photo by MAJ Garrison Spencer, USACE Public Affairs Officer) that deliver the flexibility are glossed over. The actual crossing sites, routes, engineer regulating point locations, and exact loads expected on each raft require details that are out of reach of the division. Battalions must execute the focused preparation of the battle field and generate the graphic control measures for their brigades and divi sions. Maneuver and engineer bri gades and battalions must design the crossing area so that it achieves flexi bility by developing four crossing ar eas, and the route or corridor network required to access each of them from various waiting areas. A firm under standing of the cross-mobility corridors will be critical, and programming that into the graphics at the outset provides the desired flexibility. The four sites also build opportunities for deception and viable alternatives to the typical two site planning factor for a brigade. Additionally, doctrine prescribes stag ing, holding, and call forward areas – each marshalling large formations and under the control of a Military Police element. We believe that in practice, in the face of the current and future operational environment, this is no longer a tenable course of action. Large electronic and physical signa tures will only invite enemy disruption efforts, and maximum effort should be applied to creating dispersed and con cealed formations. With that in mind, we, and others recommend application of staging and holding zones, where units are dispersed and under the con trol of their brigade or battalion to be directed toward the crossing sites, rather than MP controlled areas. The echeloning or funneling of units based on their size through the crossing site should be maintained. Beyond the graphics, likely only at the battalion level will there be enough un derstanding of the scheme of maneu ver and the rolling composition of each formation to plan march serials and the individual raft loads they will com prise. In a contested wet gap crossing against a peer threat in large-scale combat operations, it is expected that we would employ rafting operations for most of the crossing. Rafting pro vides greater survivability, natural dis persion, and improved flexibility while sacrificing the speed at which combat power can be trafficked to the far-side.

Winter-Spring 2024 Multi-Role Bridge assets are extremely scarce and the less reliant we are on fixed sites the more survivable we can expect to be. For crossings of this type, an execution checklist may be de veloped at the division level, but the mechanics of moving companies across a gap, raft by raft, is extremely chal lenging to capture. That granularity ex ists at the battalion level, and we owe that detailed portion of the planning. We experienced firsthand how power ful and how fast we could be when equipped with an order of movement containing by vehicle composition in formation and a desired scheme of ma neuver on the far-side. The micro-routing decisions concerning conges tion, enemy contact, and inactive crossing sites were natural and well in formed. Doctrine, inexplicably, assigns the development of the unit move ment and crossing plan to the trans portation officer to be executed by the provost marshal section in accordance with their traffic control plan. This de sign is clumsy, in that neither of those elements are positioned to react to changes and make rapid decisions, and there is considerable risk that they do not understand enough of the nuances of the battalion schemes of maneuver across different crossing sites to rec ommend decisions that even support the plan. We believe it is far superior to have brigade and battalion staffs de vise the crossing plan and provide re finement to the specified tasks from division. To summarize, brigade and battalion staffs executing wet gap crossing oper ations should – make every effort to closely integrate and build organiza tional relationships and trust. They should collaboratively design the cross ing area with a network of mobility and cross mobility corridors to create the flexibility to cross at any of four sites from any origin. This crossing area should also feature dispersed staging and holding zones to provide surviv ability to their formations. And they should recognize that rafting opera tions are the preferred mode of cross ing and that brigade and battalion staffs own the crossing plan – com plete with sequence of units to specif ic locations and high resolution com position of unit crossing element. During Remagen Ready, our key leader rehearsals on the terrain were invalu able. They enabled us to confirm the trafficability of different routes and confirm redundant communication across command posts and nodes. Af ter our rehearsal, we changed the routing from the holding areas to the call forward areas because many of the routes were not traversable due to rain. However, it is unlikely units will be able to conduct the same type of re hearsals during LSCO. Therefore, re connaissance units must put the same effort into identifying suitable routes through and across zones as they due to the identification of the crossing sites themselves. This emphasis must be added to future wet-gap crossing doctrine. ATP 3-90.4 affirms the importance of reconnaissance to facilitate a wet gap crossing. However, it does not provide the specificity required to ensure units execute the necessary reconnaissance. For example, ATP 3-90.4 states “a divi sion reconnaissance element moves ahead of the main body to conduct re connaissance of the near side and pre determined crossing sites.” Therefore, the doctrine must be updated to add three specific reconnaissance require ments to facilitate a wet gap crossing. First, lead reconnaissance efforts must identify suitable locations within the different zones for follow on forces to stage. Secondly, they must validate communications capability at templat ed C2 locations. Finally, they must identify mutually supporting routes that can support movement to multi ple crossing sites. Without these re connaissance efforts, units will strug gle to achieve the gap-crossing funda mentals of extensive preparation, traf fic management, and speed. Reconnaissance must be a deliberate portion of the extensive preparation. That enables the traffic management and the speed. A route will inevitably shut down at some point. We had routes shut down due to enemy ac tions, recovery operations, and degra dation of the route due to so much Figure 3. The Crossing Area Headquarters – A small control cell, consisting of battalion operations officers and their vehicles, managed the flow of equip ment through the crossing area. Each element had clear lines of both commu nication and control with their subordinate elements throughout the opera tion. The proximity of these nodes allowed for rapid decision making, tactical flexibility and limited detection. (U.S. Army photo by MAJ John A. Kearby)

Winter-Spring 2024 traffic. Fortunately, we identified deci sion points throughout the system to redirect traffic to different call forward areas and crossing sites. Furthermore, we had our CPs and RETRANS posi tioned in a manner that enabled us to communicate throughout the crossing area. As units prepare to execute these operations in LSCO, they must ensure their reconnaissance identify multiple approach routes/cross mobility corri dors and locations that provide the best communications throughout the crossing area. Command post functions ATP 3-90.4 includes a lengthy discus sion concerning command post func tions and their activities during a de liberate wet-gap crossing. While these are useful and appropriate actions in general – they offer an unrealistic per spective of echelons where these ac tions are taking place and imply a phys ical structure that is infeasible consid ering the operational environment. The final section to be addressed with in this techniques publication, is how and with what structure a wet-gap crossing operation should be com manded and controlled. The ATP delineates the roles of cross ing area commanders and crossing area engineers at both the division and brigade levels. While the descriptions of their responsibilities are generally accurate, the manual either under states or omits crucial details and com position. At the brigade level, the crossing area engineer assumes the role of the bri gade commander unless delegated otherwise. This individual, likely highly mobile, seeks a comprehensive battle field perspective through personal evaluation and dialogue with battalion commanders. However, due to this mo bility, they may not consistently be available to address tactical problems. Like the crossing area commander, the crossing area engineer, who is the en gineer battalion commander responsi ble for the crossing area, circulates the battlefield to gain understanding and shape the larger operation. Periodic contact and decision points facilitate major decisions between these individ uals, including when to assault cross, raft, commit to full enclosure, expand to two-way traffic, or change crossing sites. Mechanical decisions and those in re sponse to friction must occur else where, leading to the proposal of the crossing area headquarters. Despite the doctrine implying that this should be the brigade main command post (MCP), in practice, this setup appears disconnected and indirect. The brigade MCP, situated on the border of the crossing area, is often too far removed from the sites to have accurate infor mation for effective flow control. The suggested solution is a crossing area headquarters comprising elements from the engineer battalion TAC at var ious crossing sites and a tactical com mand post (TAC) element from which ever maneuver battalion(s) are within the crossing area. This structure offers several advantag es. The crossing maneuver battalion possesses an immediate understand ing of unit composition, a clear grasp of the scheme of maneuver and open lines of communication with subordi nates. This internal control element within a crossing battalion can provide instant agility in rapidly changing con ditions. Rafting, the likely preferred mode of crossing, necessitates thoughtful serial design and routing to avoid congestion, and crossing battal ions inherently understand this about themselves. Battalions are better equipped to inform engineer head quarters about the details of individu al elements, avoiding disruptions to the plan. Furthermore, battalions understand the scheme of maneuver at the appro priate level, allowing for correct rout ing of small elements. Rigid march ta bles and pre-arranged plans, if left to chance, risk too much when things do not unfold exactly as expected. The en gineer TAC element, having clear lines of communication with subordinates managing crossing sites, understands real-time conditions and capacities at each site, facilitating anticipation of crossing rate changes and degrading site conditions. The proposed crossing area headquar ters is dynamic and fluid in composi tion, with a constant engineer battal ion TAC element and a presence from the actively crossing battalion, ensur ing proximity to crossing sites while maintaining dispersion, facilitating rap id decision-making, and providing the necessary guidance to maintain tempo. Conclusion Unfortunately, ATP 3-90.4 mistakenly describes wet gap crossing operations in high-flying abstractions and fails to appropriately address the mechanics required by the battalions and brigades trying to execute them. The manual must be updated to provide practical and actionable tasks to staffs and units at the appropriate echelon so that they are equipped to confront the modern battlefield and this mission set. Re move the romanticized vision of grand wet-gap crossing maneuvers and reori ent on the details that will enable suc cess. With improved guidance regard ing planning at echelon, revised recon naissance objectives, and command and control techniques that consider the modern battlefield the ATP 3-90.4 can be a powerful tool for conducting wet-gap crossing operations. MAJ Korey Gaines is the S-3 officer, 2nd Battalion, 8th Cavalry Regiment, 1st Ar mored Brigade Combat Team (ABCT), 1st Cavalry Division, Fort Cavazos, TX. His previous assignments include G-35 officer, 1st Cavalry Division, Fort Cavazos; director, Cavalry Leaders Course, Fort Moore, GA; commander, Headquarters and Headquarters Com pany, 1st Battalion, 6th Infantry Regi ment, Fort Bliss, TX; and commander, Company C, 1-6 Infantry, Fort Bliss. MAJ Gaines’ military schools include Air Assault Course, Army Reconnais sance Course, Cavalry Leaders Course, Maneuver Captain’s Career Course, Joint Firepower Course, Common Fac ulty and Developer Course, and U.S. Army Command and General Staff Col lege. He has a bachelor’s of arts degree in marketing from Texas A&M Univer sity, a master’s of science degree in po litical science and a master’s of science degree in operational studies from

CGSC.

MAJ John Kearby is the operations officer (S-3), 20th Engineer Battalion, Fort Cavazos, TX. His previous assignments include chief of operations, 36th Engineer Brigade. Fort Cavazos; assistant professor,

Winter-Spring 2024 Department of Mathematical Sciences. U.S. Military Academy, West Point, NY; commander, Company A, 91st BEB, 1ABCT, 1st Cavalry Division. Fort Cavazos; and task force engineer, 2-12 Cavalry, 1st ABCT, 1st Cavalry Division. His military schools include Engineer Basic Officer Leader Course, U.S. Army Air Assault School, U.S. Army Airborne School, and U.S. Army Ranger School. MAJ Kearby has a bachelor’s of science degree in civil engineering from the U.S. Military Academy, West Point, NY. Acronym Quick-Scan ABCT – armored brigade combat team ATP – Army techniques publication CGSC – U.S. Army Command and General Staff College FM – field manual JLTV – Joint Light Tactical Vehicle LSCO – large-scale combat operations MCP – main command post MRBC – Multi-Role Bridge Company TAC – tactical command post USACE – U.S. Army Corps of Engineers He also has a master’s of science degree in civil engineering from Missouri University of Science and Technology and a master’s of science degree in operations research from North Carolina State University. MAJ Kearby’s awards include the Meritorious Service Medal with 1st Oak Leaf Cluster. Notes 1 ATP 3.90-4, Combined Arms Mobility, Paragraph 4.25.