Download the full article here: No. 25-973, Sustaining an Island Chain Campaign (Apr 25) [PDF - 1.7 MB]

Sustaining an Island Chain Campaign

Sustainers are fundamentally trained in the concept of echeloned trains, which outlines the sequential process of moving supplies from the Corps Support Area to the Logistics Release Point and, ultimately, to the maneuver unit in need. This critical process is emphasized during every combat training center rotation across the U.S. Army, from the National Training Center in California to the Joint Multinational Readiness Center in Germany.

A key element of echeloned sustainment is the spacing between sustainment nodes. For example, the Brigade Support Battalion (BSB) is typically located no more than 30 kilometers from the forward line of troops (FLOT). This proximity allows for flexibility in times of crisis or when responding to enemy activity, enabling nodes to bypass intermediate sustainment echelons, such as the Combat Trains Command Post (CTCP), and deliver supplies directly from the Brigade Support Area to the Logistics Release Point. However, unique challenges arise when the Brigade Support Area is positioned more than 300 kilometers from the FLOT, with a large body of water obstructing ground-based resupply.

Campaigning across island chains introduces complexities to traditional Army sustainment operations, necessitating innovative approaches to logistics. The Brigade Support Battalion must extend planning horizons to account for the additional time and distance required to ensure that supplies reach the individual rifleman effectively and efficiently.

Building the Right Sustainment Task Force

Unlike traditional overland campaigns, island chain operations present significant challenges in redistributing sustainment assets across the battlespace. This reality places a heightened emphasis on designing an effective sustainment task force while building the concept of support. The scarcity of strategic transportation assets, such as Army watercraft and rotary or fixed-wing aircraft, often prevents entire sustainment organizations, like a Forward Support Company, from fully deploying in support of their maneuver Battalion.

These challenges are further compounded by the limitations of seaports and airports, as well as unpredictable local weather conditions. For instance, runways may be too short, or adverse weather may prevent a C-17 from utilizing its full available cargo load (ACL). Similarly, seaports with shallow berths may be unable to accommodate a Large, Medium-Speed Roll-on/Roll-off Ship (LMSR), which can transport entire battalions or brigades. Instead, only smaller, slower-moving Logistics Support Vessels (LSVs) may be able to access these ports, limiting the scale and speed of resupply operations.

Logistics planners must be well versed on the capabilities and limitations of every delivery platform in both the Army and Joint inventory. Given the rapid pace of Transportation in Contact fielding, maintaining situational awareness of capabilities and limitations of delivery platforms is critical. Figure 1 depicts an Infantry Squad Vehicle being loaded onto an Army Chinook helicopter.

To overcome these constraints, sustainment planners must closely collaborate with maneuver planners to assess the availability and type of strategic platforms required to deploy a task force to another island. They must also determine the minimum sustainment force necessary to support the maneuver unit throughout the campaign. This often entails making difficult prioritization decisions: should cargo trucks, command and control platforms, artillery, maintenance and recovery vehicles, or gun trucks take precedence? These trade-offs demand a strategic approach, balancing operational needs with logistical feasibility in a complex and resource-constrained environment.

Determining the Requirement

After determining the size of the maneuver task force and its supporting sustainment task force, the next critical step is to identify requirements, evaluate capabilities, and address any shortfalls. However, determining these requirements is often more complex than it initially appears.

One of the foundational lessons from the Theater Sustainment Planners Course at the Command and General Staff College is the concept of "theater stockage levels." This involves calculating how many days’ worth of each supply are needed in theater to sustain ground forces—be it one day, ten days, or more. Accurately determining theater stockage levels requires a deep understanding of strategic supply chain time-distance analysis. For example, how long does it take for fuel to travel from its origin to the Joint Security Area (JSA)? How much bulk fuel can the JSA store at any given time, and how many days of supply does that storage represent?

These principles are directly applicable to brigade-level planning for an island chain campaign. If a battalion is located 300 kilometers away on a separate island, how long will it take to deliver each class of supply to them? If the Brigade Support Battalion (BSB) needs five days to deliver fuel to a Forward Support Company (FSC) on another island, then the FSC must maintain a minimum of five days’ worth of fuel on site.

Here is where the concept of support becomes both challenging and dynamic. Typically, a Forward Support Company carries only one to two days’ worth of supplies. Now imagine that, due to strategic transportation constraints, only half of its fuel storage equipment successfully deploys to the island, leaving the FSC with a single day of supply. In such cases, the Brigade Support Battalion must employ the entire joint network to establish a five-day fuel supply on the island, while also developing contingency and emergency resupply methods.

To build the initial five days of supply, the BSB might conduct aerial deliveries of 55gallon and 250-gallon fuel drums using Container Delivery System (CDS) bundles and 8 or 12-foot heavy equipment platforms. These supplies can be dropped directly to the maneuver unit or pre-positioned in supply caches. Additionally, the BSB can request joint aircraft support to conduct "wet wing" operations, during which rotary, tilt-rotor, or fixed-wing aircraft land and execute hasty refueling operations at a Refuel-On-the-Move (ROM) site for the maneuver unit. These creative approaches exemplify the ingenuity required to sustain operations in the unique and challenging conditions of an island chain campaign.

Managing a Joint Distribution Network

Developing a robust concept of support for an island fight hinges on redundancy. Due to the inherent vulnerabilities of resupply methods to enemy actions and unpredictable weather conditions, every supply type must have a well-structured Primary, Alternate, Contingency, and Emergency (PACE) plan.

Expanding the sustainment network and fully leveraging assets across higher headquarters and theater-level resources are essential steps in this process. Equally critical is understanding how to secure transportation assets for resupply. This involves coordinating with the Division Transportation Office and the Brigade Aviation Element to acquire transportation modes and working with the Division Sustainment Brigade Support Operations Office (SPO) for aerial delivery and rigging support. Figures 2 and 3 depict strategic assets that can be used to deliver Army resources as part of the distribution network.

Planning horizons play a vital role in this context. Aligning aircraft or watercraft for resupply operations typically requires at least four days' notice to source, rig, deploy, and execute missions effectively. The Brigade Logistics Synchronization (LOGSYNC) meeting and daily Logistics Status (LOGSTAT) reports must address operational requirements and resource shortfalls five to six days in advance to ensure readiness.

Effective planning also demands rigorous red-teaming. The support operations cell within the Brigade Support Battalion (BSB) must proactively identify potential threats, including enemy interference and adverse weather, to assess risks to the supply chain and develop mitigation strategies.

Every critical support function—such as maintenance and recovery, off-island Casualty Evacuation (CASEVAC), personnel replacement, power generation, water and other classes of supply, and even human remains collection—must be incorporated into the joint distribution network. This network, managed and executed by the BSB, is the lifeline of sustainment in the complex and volatile environment of an island campaign.

Conclusion

Effective sustainment operations in an island chain campaign demand innovative planning, meticulous coordination, and adaptability to overcome unique logistical challenges. The concept of echeloned sustainment, while rooted in traditional overland operations, must be reimagined to address the complexities of distance, strategic transportation limitations, and environmental factors inherent to island warfare. Sustainment planners must prioritize the design of a robust and agile task force, balancing competing priorities such as fuel, transportation, and mission-critical equipment.

By leveraging joint capabilities, implementing redundancy through comprehensive PACE plans, and maintaining proactive synchronization with maneuver and higher headquarters elements, sustainers can mitigate risks to the supply chain. Anticipating requirements, planning for contingencies, and executing with precision ensure the maneuver force remains supported and operationally effective throughout the campaign. Ultimately, the success of sustainment in these environments lies in creativity, foresight, and a relentless commitment to ensuring the logistical lifelines remain intact, even in the most demanding conditions.

MAJ Sean McLachlan currently serves as the Support Operations Officer for the 225th Light Support Battalion, 2d Light Brigade Combat Team, 25th Infantry Division at Schofield Barracks, Hawaii. He was previously the 25th Infantry Division Transportation Officer and is about to transition to the Deputy G4 for 25ID. MAJ McLachlan’s civilian education includes a Bachelor’s Degree in International Studies from the Virginia Military Institute, a Master’s Degree in Military History from Norwich University, a Master’s Degree in Military Art and Science from the U.S. Army Command and General Staff College, and he is currently a PhD Candidate in History at Liberty University. MAJ McLachlan was recognized as the 2024 LTG Arthur Gregg Sustainment Leadership Award winner and as the 2023 and 2024 Transportation Corps Field Grade Officer of the Year.