From the Amphibious Force to Expeditionary Seabasing: Supporting Mobile Basing as a Strategic Capability


By Robbin Laird

I have argued that under the impact of the Osprey and the F-35B, the ARG-MEU is evolving into something more akin to a modular amphibious task force. As the U.S. Navy works ways to more effectively integrate such a development with the wider fleet, the emergence of new ways to build out the amphibious force into an expeditionary sea based force supporting the broader joint force have emerged as well.

I continued the discussion with Jim Strock with regard to this strategic trend as well as its importance. Jim Strock is the former Director of the Seabasing Integration Division at the USMC and an expert on the evolution of seabasing for the current force.

Why would one want to have an expeditionary seabasing capability?

Jim Strock: “The reason you need mobile bases in concert with fixed sites ashore is you’ve got to overcome the tyranny of time and distance. If you think of mobile bases operating in the Western Pacific, there’s a tremendous number of assets at the Navy, Marine Corps, and joint level that could be brought to bear and configured to accomplish a selected or certain type of missions by reconfiguring those assets into an expeditionary seabasing concept of operations.”

A key opportunity lies in reconfiguring platforms and assets which the joint force currently has into an expeditionary seabasing template. The Marines and now the U.S. Navy have Ospreys; the joint force have F-35s with the Marines having the most expeditionary version, the F-35B; and the Marines are adding a new heavy lift helicopter, the CH-53K, which can embed into the digital world of a kill web enabled force.

Strock also highlighted the importance in terms of capabilities which the joint force already has of what used to be called Joint High-Speed Vessels. There are 15 such vessels in the program, and they are now called Expeditionary Fast Transports or EPFs. Strock underscored: “They have substantial capability as part of a mobile base to sprint and deliver assets and personnel to selected locations. You’ve got other connectors that are in the pipeline.”

“Those ships can carry 600 short tons at 35 knots 1,200 nautical miles in sea state three. They have berthing for 104 embarked troops that they could keep for 14 days. They’ve got business-class airline seating for 312 troops that you could keep onboard for four days. They’ve got mess decks where they can feed them.

“They’ve got a 20,000-square-foot mission deck which was designed wide enough that you can drive a seven-ton truck and a trailer onto the mission deck, go forward, do a horseshoe turn, and come out the rear end again without having to back up. And then the flight deck is capable of launching or recovering 53 Kilos, and with certain flight deck coatings, could launch and recover V-22s. That’s all in the window sticker standard equipment right now on an EPF.”

The current Commandant of the USMC has highlighted the need to develop a light amphibious warship. Such a future capability may come to fruition or not, but Strock highlighted how the EPF could fill the gap.

Strock noted: “The only requirement they do not meet compared to the requirements for the Light Amphibious Warship is the EPFs cannot beach. And that’s a critical capability necessary to support Expeditionary Advanced Base Operations forces.  However, back in 2009,  the Army actually ran some experiments connecting  a Lightweight Modular Causeway System to the stern of a Joint High Speed Vessel and demonstrating the vessel’s ability to transfer equipment to unimproved beaching sites.

“In other words, the EPF is one of several platforms that are available right now for testing, demonstration, and proof of concept events with causeway systems at the joint level for expanding expeditionary sea basing capabilities.”

Put another way, by reshaping concepts of operations, in this case shaping expeditionary seabasing capabilities and projection of power ashore in a mobile basing construct, one can find key elements within the extant force which can be leveraged.

And even more importantly, we can build more such platforms at known cost points.

Expeditionary seabasing fits nicely into the strategic shift in force structure operations which I have referred to as modular task force operations, whereby one can mix and match platforms in a presence force and through connectivity can reach back to other force elements to augment the capabilities of that presence force.

Strock discussed the modular nature of the expeditionary seabase as follows:  “No two sea bases will ever be the same and no two mobile bases will ever be the same. They’re configured to do what they need to do.

“For example, a mobile base could operate as a maneuverable, survivable, sea-based node with any broader network of land-based and sea-based infrastructure sites designed to support the joint force in whatever operating environment it’s in. It cold be a single ship or multiple ships.

“And these mobile bases can bridge the gap between land-based sites and extend the operational reach of many of the new naval platforms that are in the program right now, to include manned and unmanned vertical and surface connectors.

“And logistically, the mobile base can serve as an intermodal transshipment point between strategic, operational, and tactical logistics pipelines, wherein the mobile base can receive supplies and equipment from strategic sealift shipping, reconfigure those assets into tailored support packages for supported units, and then the mobile base can make pre-planned or on-call deliveries to forces ashore via manned and unmanned vertical, surface, and undersea connectors.

“In effect, the mobile base is an afloat intermediate support or staging base that is not encumbered by a fixed or land-based site located within enemy threat range. And when I talk about strategic sealift shipping, if you’re in an extended duration operation and ultimately one of your sources of supply is the continental United States, supplies often times leave the continental United States via commercial shipping in 20-foot and 40-foot containers.

“You’ve got to have platforms at sea that can receive containerized supplies and break them down into what I call user-friendly units of issue.  Some gunnery sergeant on an island with a platoon of Marines doesn’t want two or three 20-foot containers dropped on him. He needs supplies that are far more tailored to support his operations. In other words, the mobile base can provide support when and where needed without overloading the logistics support capabilities currently planned to be positioned for forces ashore.

“And the Office of Naval Research has developed motion-compensated cranes, advanced mooring systems, and environmental ship motion forecasting capabilities that, when fully integrated, would be able to provide an at-sea precision lift and cargo transfer capability between vessels, thereby bringing seabased intermodal transfer to reality.”

“Such logistical capabilities are crucial to have a sustainable force. New assets like the Next-Generation Logistics Ship and the Light Amphibious Warship will be able to maneuver forces to faraway places, but unless those platforms have enough capacity to go back to where they came from without being replenished, when they get to their point of delivery, they may need to be refueled, potentially consuming assets that were originally positioned  for the units that need them.

“The idea of a mobile base being able to close in, launch and recover aircraft and surface craft  to resupply and replenish forces ashore, and then move out to rendezvous points to interface with strategic sealift shipping to  re-stock, is significantly different.

“If the force has mobile platforms, large ones that can give you an intermodal transshipment capability at sea, you can extend the operational reach and duration of your logistics platforms, be they vertical, surface, undersea, manned or unmanned.”

There is a clear need to have a realistic understanding of the challenge of sustainability and persistence in the distributed operating environment. Logistical support nodes are the definer of what the force can do from a persistence point of view. And with the very significant shortfall of military sealift command assets and their priority focus on supporting the strike fleet, that leaves a huge gap in how to support a forward deployed force projecting power into an area of interest.

Shaping expeditionary seabasing concepts of operations and building the key nodes in such a con-ops can support mobile basing as a strategic capability for the joint and coalition force going forward.

Strock raised a key point with regard to Host Nation Support and logistical sustainability.

A key advantage of an expeditionary seabasing con-ops is that the United States owns the key parts of the expeditionary seabasing force. While host nation support agreements would likely be part of any persistent stand-in force concept of employment, the joint force does not necessarily have to rely in the good will of Host Nation Support partners in a future crisis.

We closed by discussing the potential synergy between modular task forcing and modular ships which could enable such a task force. “One can clearly design ships to accommodate varying types of missions through the introduction of additional and/or updated baseline ship configurations.

“In other words, the ship really needs to have an open architecture with residual space, weight, and power to support current and emerging capabilities. Through the use of flexible ship general arrangements, you could facilitate the timely reconfiguration of ship compartments and spaces to meet the evolving requirements or what one might call adaptive modularity.”

He added that one could build in what one might call configured modularity, and that’s where you have individual capability sets that are already configured, or containerized, or packaged, where they could be put on any number of different platforms in order to accomplish a mission.

In other words, “if you focus on the point that platforms need to be thought through in their ability to rapidly reconfigure and readily adapt, and to accomplish other selected missions, such a capability could clearly empower expeditionary seabasing and its ability to support configurable modular task forces.”

We have recently published two books which highlight key aspects of why mobile basing is a key part of the redesign of effective concepts of operations going forward for the joint force. The featured graphic highlights one of the chapters in the making of the kill web book. 

The USMC Transformation Path: Preparing for the High-End Fight

A Maritime Kill Web Force in the Making