Category Archives: Capability Pitch Week

The NightTrain: Unmanned Expeditionary Logistics for Sustaining Pacific Operations

Pitch Your Capability Topic Week

By CDR Todd Greene

“It is very clear to me that logistics, among the warfighting functions, is the one that we need to make the most progress on right now…My number one focus is logistics, logistics, logistics.” –General David Berger, Commandant of the U.S. Marine Corps, May 23, 2023.

During a future conflict, the USMC may be operating multiple Expeditionary Advanced Bases (EABs) on dispersed islands across the Western Pacific. Within their respective island groups, the bases may reposition frequently to complicate enemy targeting. These EABs would either be established prior to the conflict while access was open, or they would be forcibly established with the joint support of naval assets fighting their way in. But naval support may not be accessible enough to provide steady logistical support to advance bases. This is an acutely challenging problem for EABs and demands innovation.

The USMC is aware of the logistics challenges accompanying their shift in doctrine against a peer adversary. There are many efforts to address the problem, but none cohesively solve it end-to-end. A solution is needed to address not only the challenges of long-distance contested transit across the open ocean, but also the last mile from sea to shore. A new, simple, and survivable system and its attendant concepts of operation could address these challenges and help provide consistent logistical support to stand-in forces.

Revising the Iron Triangle

Supplying widely distributed EABs of varying size, composition, and organic capability presents two sets of challenges – long-range transits across thousands of miles of contested open oceans, and last-tactical-mile delivery over an unimproved shoreline and into the hands of stand-in forces. Today’s systems mainly focus on one or the other, but there is nothing that can do both well.

Innovation must be directed at designing connectors that can bridge capability between these two distinct challenges. They must be able to transit oceanic spaces that feature hostile environments stemming from the open ocean environment and adversary capability. After traversing these many miles, the same system must somehow get supplies across a beach and into the hands of the stand-in force. Innovative connectors are necessary to provide the vital link between the stand-in forces and seabases or logistics hubs.

To help define the design of a new, innovative logistical connector it is important to first articulate and prioritize the system’s characteristics. Historically, a system that carries a payload is constrained by what is referred to as the “Iron Triangle” – range, speed, and payload weight. To increase performance in one area, the other two must suffer. Typically a tool cannot go fast and far while carrying a large load. Designers must pick one attribute to emphasize, or accept compromises across all. While these three traditional characteristics are still valid, the unique attributes of the transoceanic contested logistic problem leads to a revised iron triangle – efficiency, survivability, and cost.

Efficiency must be a driving consideration in any attempt to solve a problem when a cargo is being transported. Efficiency is often gauged by Freight Ton Efficiency (FTE), and measured in cargo ton-miles per gallon. When framed within the transoceanic lens, the optimized solution to move a variety of cargo already exists – the large containership. Unfortunately, a containership does not effectively meet the other two criteria.

By layering the additional need to not just cross an ocean, but cross a contested ocean, survivability must also be considered. The most efficient solution is no longer viable, since the typical containership is not survivable in wartime. Specifically, it is susceptible to targeting, vulnerable to attack, and does not have any ability to recover mission capabilities after suffering damage. Looking toward historic examples for design inspiration, the survivable solution to transoceanic contested logistics has historically been an escorted convoy.

The first two attributes of our revised iron triangle push the design solution for contested logistics in the direction of large commercial shipping, escorted for thousands of miles by an assortment of warships capable of providing area defense against a variety of multi-domain threats. The reality of available resources makes this a nonviable solution. By taking cost into consideration, the optimum solution becomes something simple, easy to build, and ideally shifts the enemy’s detect-to-engage calculus to where it becomes more expensive to find and kill the logistic system than the system itself. An example of a system matching this description is a simple steel barge.

The revised iron triangle is pushing for an innovation that features the best attributes of a containership, an escorted convoy, and a simple steel barge. How do we best combine these attributes and cross the shoreline?

Early Era Submarines and Narco-Subs

An emerging area of research being done at the Naval Academy and other facilities is in the specific hydrodynamic attributes of semi-submersible vessels (SSVs).1 This research has combined computational fluid dynamics, experimental tow tank testing, and parametric analysis of past and present examples.

Seagoing vessels are typically categorized as a surface ship, with the majority of the hull and superstructure existing and operating above the waterline, or as an undersea vessel that operates primarily completely submerged. A semi-submersible vessel is a hybrid that combines the properties of a surface ship and submarine to partially immerse, minimizing its above-waterline profile, while still remaining on the surface at all times. Yet only about 15-20 percent of a semi-submersible’s volume is above the surface.

In contrast to submarines, an SSV is dramatically simpler in both propulsion and structure. Due to its access to atmospheric air it can be propelled by standard internal combustion engines. It does not need to withstand high hydrostatic pressures since it does not dive, thus eliminating the costs to produce a vessel that can withstand oceanic pressure while submerged. It does not need control surfaces and mechanisms to maneuver sub-surface in three dimensions, further reducing cost.

By operating with a significant fraction of the hull submerged, the SSV differentiates itself from a surface vessel. Being in this semi-submerged regime has obvious advantages in reducing its observable signature. Additionally, there are significant wave-making resistance reductions, in the right conditions, discussed below.

World War I and II submarines frequently operated in a semi-submerged state, and a review of their operational and design parameters provides some instructive guidance for a modern SSV design. A statistical analysis revealed that significant operational advantages were realized in these early designs by optimizing the length to beam ratio and the speed to length ratio. A second, supporting parametric analysis was conducted on the only valid example of a semi-submersible operating in significant numbers today – the narcotics smuggling “narco-sub.” The results agreed with the early era submarine analysis and pointed to potentially advantageous design characteristics.

The U.S. Navy submarine USS Wahoo (SS-238) steaming off the Mare Island Naval Shipyard, California in a semi-submerged state on July 14, 1943. (Photo via Wikimedia Commons)

Using these historic and modern-day examples as a starting point, a set of computational and physical experiments were envisioned and conducted. The results of the experiments confirmed that there is indeed an efficiency advantage to be had by a semi-submersible if the SSV geometry is optimized and it is operated at the best speed.2 In other words, given two identical hulls, one operated primarily as a surface ship, the other operating semi-submerged, the semi-submerged hull can have less drag at the optimal speed.

With the knowledge that a SSV can be both more efficient and lower signature than a comparable surface vessel, the focus shifts to optimizing cost. If all three characteristics can be met, the foundation is laid for the next innovative contested logistics platform.

The Physics (and Beauty) of Shipping Containers

The intermodal shipping container needs no introduction. Nominally a rectangular container, measuring 20 feet in length, 8 feet wide and 8.5 feet high, is known as a TEU (twenty-foot equivalent unit). Many variations exist – 40-foot containers, 10-foot containers, Quadcons, High Cubes – but all retain the standard interfaces that allow them to be interchangeably loaded onto a ship, train, truck, and other forms of transport. The intermodal container is the innovation that unleashed the level of efficiencies now seen in transoceanic commerce. This innovation is very powerful in its end-to-end efficiency and must also be applied to optimize cost within the contested logistics problem.

The same characteristics that make the TEU containers valuable for peacetime commerce make them vital to solving contested logistics. The standardized sizes and interfaces not only make loading simpler, it means the material handling equipment to load, unload, and maneuver cargo is mature and universally available. When it comes to cost and production, shipping containers are not hard to acquire and they can be manufactured at many small-scale industrial facilities. Many existing military systems are already designed to be containerized and tens of thousands of containers are immediately available to DoD. Millions of containers are accessible in ports globally today.

U.S. Marine Corps Cpl. Jonathan Perez, a landing support specialist with 3rd Landing Support Battalion, secures a quadcon to a palette during an Alert Contingency Marine Air-Ground Task Force (ACM) drill at Kadena Air Base, Okinawa, Japan, Jan. 11, 2023. (U.S. Marine Corps photo by Lance Cpl. Sydni Jessee)

Unfortunately, it is not unheard of for shipping containers to be lost overboard. While not good for commerce, this gives us insight to another attribute that can be leveraged for innovation. Like a ship, a container that is immersed in seawater will sink to the point where the weight of water displaced by the container is equal to the weight of the container. This is known as Archimedes Principle. Hence, a fully laden 20-foot dry container will float for a time. This is because the volume of a 20-foot container is approximately 1,300 ft3. If it were to be fully immersed, it would produce about 83,000 pounds of buoyant force pushing it up, which is more than the 53,000 pounds of gross allowable weight of the container. Much like a semi-submersible, a fully loaded 20-foot container will therefore float with about 15-20 percent of its surface showing above the waterline, until it fills with water and sinks.

Containers come in many shapes and sizes, but only fit together in certain standard arrangements. Logisticians can choose the building blocks necessary to solve the contested logistic problem, while optimizing the freight ton efficiency, and ensuring compatibility with the receiving unit’s material handling capability. Building on conventional container variants, several unique container designs can optimize the opportunity presented by these systems.

  • Commercially available containers (Figure 1):
    • 20-foot TEUs – standard worldwide.
    • 10-foot TEUs – same height and width as a 20-foot container, but half the length.
    • “Quadcons” – same height and width as the 20-foot TEU, but a quarter of the length, and four fit in the footprint of one TEU.
  • Unique containers envisioned for this system, featuring small departures from the current container variants (Figure 2):
    • Half 20-foot – a standard 20-foot TEU split in two lengthwise, resulting in a container 20 feet long, 8.5 feet high, but only 4 feet wide.
    • Buoyancy wedge – triangular prism with the same footprint as a Quadcon.
    • Propulsion wedge – same dimensions as a buoyancy wedge, but with an installed battery-powered waterjet.

Figure 1: A sample of the standard, commercially available, container variants. (Left to right: Quadcon, 20-foot ISO container, 10-foot ISO container. Author graphic.)

Figure 2: Unique Containers envisioned for this system. (Left to right: Buoyancy wedge, Half-20-foot container, Propulsion wedge. Author graphic.)

Putting it Together: An End-to-End Solution

The system’s functional objective is resupply of distributed stand-in forces. The innovative contested logistic platform proposed is called NightTrain. It consists of an unmanned core semi-submersible, a strongback chassis, plus an assortment of standardized containers. The core vessel uses the hydrodynamic findings from the current and historic research to be optimized in shape and speed for long range transit across a variety of sea states, while being mostly submerged and therefore low-signature. It is autonomous and reusable, while housing the navigation and propulsion systems. It is attached to a cargo section through the strongback and propels the combined vessel.

Multiple cargo containers augment the core SSV. Arrangement of the containers is such that they link together to create the hull of the larger vessel. Loaded containers are placed on a standard commercial container trailer chassis. Like Legos, positioning pins on the trailer bed constrain the location of the containers into standardized arrangements. The loaded trailer is trucked from the warehouse to a port where the cargo containers are placed onto the strongback section of the NightTrain SSV. This strongback resembles a standard flatbed trailer. The consolidated NightTrain, with the forward two-thirds of its length being containerized cargo supported above the strongback, and the aft third being the propulsion system, is lowered into the water for departure or onto a mothership for further deployment. 

This combination of containerized shipping technology and a semi-submersible hull meets our design goals of being efficient, survivable, and low cost. It features all the benefits of ISO standardized containers, including common loading, unloading, and material handling systems and interfaces. It exhibits hydrodynamically-optimized geometry and speed, providing for reduced resistance compared with a similar surface vessel. All system sub-components are over-the-highway transportable. The core SSV is a low-tech and affordable vessel that makes for a passively ballasted and traditional air-breathing diesel vessel that can meet the contested logistics challenge.

Crossing the Last Tactical Mile

The functional objective of this system is to deliver needed supplies into the hands of the stand-in forces while minimizing the specialized equipment and training required to process supplies on the receiving end. In many cases, setting a 20-foot container adrift a thousand yards off the beach is of zero practical value. In order to offer a true end-to-end solution, it must be able to cross the beach.

Imagine as the vessel approaches an EAB a certain number of the containers are released. The core vessel continues to the next EAB, and ultimately makes the round trip back to the logistic hub. The containers are released in navigable water just outside the surfline and cross the last tactical mile in one of three ways, depending on the organic capabilities of the stand-in force:

  • Doorstep delivery via buoyant cache. The floating container is retrieved by the receiving unit using assets available to them (such as small boats or rotary wing aircraft), taking advantage of the container’s standardized connection points.
  • Concealed delivery via subsea cache. The container is ballasted to sink when released. The position of the container is known by the receiving unit and combat divers can retrieve it. Buoyancy bags inside the container can be activated by the divers.
  • Direct delivery via self-propelled containers. Standard containers are augmented by external propulsion containers (no larger than a five-foot Quadcon, Figure 3). These containers use a small water jet propulsion system to drive themselves onto a beach down a programmed line of bearing. This method may be reserved for only small units without any retrieval capability.
Figure 3: Half-20-foot container with attached propulsion and buoyancy wedges after being released from the SSV. Note the submerged water jet nozzle. (Author graphic)

Illustrative Cases

Three scenarios are offered as illustrative cases across the spectrum of possible EAB logistical demand, demonstrating the versatility of the system.

EAB #1 – Marine Littoral Regiment (MLR/F-35 FARP)

Consider the challenges of resupplying an island similar in topology as San Clemente Island, but it is not conveniently off the southern California coast. Rather, the nearest major logistical node is more than 2,500 miles away. The island is about 50 square miles, with a primarily rocky coastline, and a small relatively shallow harbor with a pier capable of mooring barges and LCUs. This is a high volume, long-distance voyage. The most constraining logistical needs are: Class III: aviation fuel, and Class V: aviation ordnance. Fortunately, this EAB features organic capabilities that can help facilitate resupply. These retrieval assets include rotary wing aircraft, a small boat unit, heavy material handling equipment, and logistics personnel (Red Patch landing support, aviation ordnance techs, and refueling techs). 

Operating from a nondescript warehouse near a commercial port in Guam, a Marine Corp logistics element receives the demand signal for 12,000 gallons of jet fuel as well as various aircraft repair parts. Two 20-foot containers are each loaded with a 6,000-gallon fuel bladder, and the bladders are filled. After being weighed, the logisticians fill one compartment of the buoyancy bladder in each container with compressed air, close the hatches, and load them on a flatbed container chassis using an overhead crane. Two additional Quadcon containers are packed with shrink-wrapped aircraft parts. These containers are also weighed and the buoyancy bags filled with air, then loaded on the trailer.

The loaded trailer (a 50-foot long combined load) is transported to the local port, lifted onto the waiting strongback, which is already attached to the core SSV. Using standard container hardware, the combined NightTrain SSV is lifted into the water, buoyancy is adjusted, diesels are started, navigation orders are loaded. It commences the 2,300 nautical mile journey to the EAB.

Approximately seven days later, having completed the contested oceanic transit, but unable to approach the island any closer than one nautical mile, the NightTrain SSV releases the cargo containers offshore. The containers float, and visual locator beacons are energized. Marines from the small boat unit, and CH-53Ks from the aviation detachment recover the floating containers. NightTrain transits back to the port where it was launched to refuel and reload.

U.S. Marines with Marine Heavy Helicopter Squadron (HMH) 461 carry a cargo container with a CH-53K King Stallion at Mountain Home Air Force Base, Idaho, Aug. 11, 2022. (U.S. Marine Corps photo by Cpl. Adam Henke)

EAB #2 – Fires EAB (NMESIS detachment)

Consider an island similar to Snake Island in the Black Sea. While a tactically significant island, it is less than one square mile in area, without much cover. This island does have a short stretch of beach accessible by vehicle. The nearest logistical support node is about 100 nautical miles away. The most constraining logistical demand is Class V: ordnance, specifically canisterized Naval Strike Missiles. The only organic processing asset available on the receiving unit’s end are the NMESIS ordnance techs.

The logistical demand for eight canisterized Naval Strike Missiles is received at the logistics hub. Four “Half-20” containers are loaded with two shrink-wrapped NSM canisters each. After weighing the loaded containers and referring to the buoyancy table, the logisticians fill two compartments of the buoyancy bladders included in the container packout. The half-20s are loaded on a flatbed chassis. Four propulsion wedges are also loaded on the chassis, one attached to the end of each half-20. The total load is 50 feet long and eight feet wide. The trailer is taken to the port, mated with the NightTrain SSV, and launched.

Zmiiny (Snake) Island geographic features. (Image via Navionics)

Upon arrival in the vicinity of the island, all four half-20s are released, each with their own attached propulsion wedge. When afloat they settle on their sides, resembling a rectangular steel barge (20 feet long, 8.5 feet wide, and four feet deep). They are released southeast of the beach on the island and a quarter mile offshore. The electric propulsion units kick on, providing enough thrust and steering control to move the half-20 containers at four knots. The navigation system drives them down the magnetic bearing of 333 until they run aground on the beach. At that point, the NMESIS teams recover the containers with their vehicles, drag them up the beach, and retrieve the missile canisters. The batteries from the propulsion wedges are also recovered and repurposed.

EAB #3 – 6-man Force Recon Team

A recon team is tasked with ES observation using a passive ground-based sensor to provide targeting information to MLR area denial weapons. This unit is positioned on Koto (Xiao-Iam Yu) Island, adjacent to Orchid Island, approximately 40 nautical miles southeast of Taiwan. There are no improved facilities on the island, although it does have a protected sandy beach on its western side and is approachable to about 60 feet of water depth. The nearest logistical support node is between 200-500 nautical miles away. The primary logistical demands are Class III (fuel, 50 gal/day) and Class I. Organic resources available to the team to participate in resupply are just one rubber craft and combat divers.

Logistical demands for 100 gallons of diesel fuel and various food stores are predicted by the logistics depot. A single five-foot long Quadcon container is filled with the supplies and fuel. After being weighed, the logisticians fill three of the buoyancy compartments with water, none with air. A cylinder of compressed air is also attached to the buoyancy bag.

The Quadcon is included with a load of seven other quadcons on a trailer, taken to the port, and loaded onto the NightTrain SSV. The SSV makes the contested transit at 11 knots, stopping at five different waypoints along its way to release various canisters. When it arrives at the island, it releases the Quadcon 250 yards offshore, which sinks to the bottom in 80 feet of water. When ready, the Force Recon combat divers go to the location, dive on the canister, open the hatch, and activate the compressed air canister to float the supplies to the surface.

Ridesharing but for Expeditionary Bases

The rideshare model has shown its value versus the traditional centrally-dispatched taxi. A customer publishes their specific need and a decentralized fleet of suppliers evaluates their own ability to meet that need. The most optimally placed and capable supplier is automatically dispatched to meet the need.

Apply this concept now to our contested logistics problem. By using a combination of standardized and novel container types, many needs of all shapes, sizes, and capabilities can be supplied. There will certainly be many different demands and logistical capabilities of EAB customers. Using a system that allows a unit to publish their need (such as specific quantities of food and fuel) and their retrieval conditions and capability (e.g., rocky coastline, no improved port or protected beach, small boat unit), capable suppliers can self-nominate to fill the demand. This ultimately results in a distributed, resilient logistic network.

The innovative connector that makes this vision possible is an unmanned semi-submersible that serves to transport containers from the source of supply to the stand-in-force. This vehicle is efficient, survivable and relatively inexpensive. It leverages the best of modern logistical and hydrodynamic efficiencies. We call it the SSV NightTrain.

Commander Todd Greene, USN, is an Engineering Duty Officer serving as an naval architecture instructor at the U.S. Naval Academy. He is a graduate of the Naval Postgraduate School and the U. S. Naval Academy. The views and opinions expressed here are his own and do not necessarily reflect those of the U.S. Navy.


1. Sung, L. P., Matveev, K. I., Morabito, M. G. “Exploratory Study of Design Parameters and Resistance Predictions for Semi-Submersible Vessels.” Naval Engineers Journal, March 2023.

2. Sung, L. P., Laun, A., Leavy, A., Ostrowski, M., Postma, M., “Preliminary Hull-Form Design for a Semi-Submersible Vessel Using a Physics-Based Digital Model.” Naval Engineers Journal, December 2022.

Featured Image: A Rough Terrain Container Handler (RTCH) moving cargo. (USMC photo)

When the Balloon Goes Up: Naval Mesh Networking with Stratospheric Balloons

Pitch Your Capability Topic Week

By Mark Howard

Coordinating distributed maritime operations, particularly in a peer-on-peer conflict, will likely prove to be a challenging problem. The environment will be heavily contested and command systems will be stressed. In particular, the communication and ISR network must be functionally reliable and resilient. Maintaining a high level of situational awareness will be critical in all aspects of operations, from the initial deployment of forces to the concentration of firepower onto targets. The C4ISR of both sides will include everything from over-the-horizon radar to subsurface listening and space based orbital assets, all of which will combine to make the surveillance grid more transparent. But sustaining the bandwidth required for communications over wide areas, especially in light of adversary jammers and the long distances between theater commanders, will be a serious operational challenge.1

The U.S. Navy efforts at electromagnetic maneuver warfare is working towards a future where there may only be a few transmitters in a battlespace while the remaining forces are all on receive.2 These efforts are beginning to leave the laboratory and work their way into the fleet, but much work remains to be done. To overcome these challenges, significant resources are being spent on improving low earth orbit (LEO) capabilities and UAV relays that are resistant to jamming. These efforts amount to building a mesh network, a network where each node connects directly and non-hierarchically to one another.3 These nodes are capable of self-forming, self-healing, and self-organizing.4 Mesh networks offer a more resilient and risk-worthy type of network that can better fulfill the needs of warfighters in a contested environment.

These emerging mesh networks, which feature a heavy reliance on space-based assets and UAVs, should be augmented by stratospheric balloons. These near-space platforms operate well above typical aircraft, but well below LEO satellites, challenging the conventional counters for high-altitude and space-based sensors. By offering a strong combination of high endurance, low cost, small footprints, and modular payloads, stratospheric balloons are poised to make major contributions to mesh networking in the battlespace.

Balloon Capabilities and Considerations

Balloon coverage is especially broad given the platform’s ability to reach high altitudes, such as covering a space over 600 miles in diameter for a balloon at 65,000 feet. The ability to operate lower than satellites enables these platforms to resolve features at lower power and at longer ranges. Considering a point at nadir, near-space balloon platforms are 10-20 times closer to their targets than a typical 400 kilometer-high LEO satellite.5 This distance differential implies that optics on near-space platforms can be much smaller to achieve similar performance, and clearly the cost of launching the capability is far less than rocket-assisted orbital deployments.

Prospective balloon coverage areas. (Graphic via Mehmet Cevat Özdemir, “Conceptual Changes By Use of Near Space.”)

Notwithstanding recent balloon shootdowns that made the news, near-space platforms are quite survivable, and their low-cost, unmanned nature makes them relatively risk-worthy. Lockheed-Martin reviewed balloons in a briefing called “Preliminary Study: High Altitude Airship Survivability and Vulnerability,”6 and concluded they have extremely small radar and thermal signatures that make them especially challenging to most traditional tracking and targeting methods. Estimates of their radar cross section were on the order of hundredths of a square meter. Considering how expansive their operating areas could be in terms of area and altitude, just finding balloons would be a challenge, let alone prosecuting a high-altitude engagement to conclusion.

Space-based assets are so heavily demanded that they have historically been difficult for tactical commanders to task. Whatever mission a local commander may need performed, there always seems to be a long line of higher-priority, strategic missions required by other commands and higher-echelon authorities. Near-space balloons would not necessarily fall under these same authorities, and could be more available battlefield assets that fall under the direct control of tactical and local-level commanders. These commanders will have many requirements of their own, but the two highest needs are likely to be persistent over-the-horizon communications and ISR capabilities. By operating many of these lost-cost platforms across wide areas, tactical commanders can have many of their information needs met.

Likely the best-known commercial balloon effort is Google’s Project Loon. This project started in 2011 with the goal of providing internet service to areas without reliable internet via a mesh network of internet balloons. When the project ended in 2021, virtually all of the technical challenges the team faced had been solved and the project successfully connected hundreds of thousands of users with networks of floating cell phone towers operating in the stratosphere. The project’s end was mainly due to financial concerns, for as the team lead wrote, “the road to commercial viability has proven much longer and riskier than hoped.” Regardless of business feasibility, technical feasibility was no longer a major concern.7 From a technical standpoint, the team accomplished many things that were previously thought impossible, such as precisely navigating balloons in the stratosphere, creating an operable mesh network in the sky, and developing balloons that can withstand the harsh conditions of the stratosphere for close to a year.

A stratospheric balloon on display at the Google Loon launch event in June 2013. (Photo via Wikimedia Commons)

One of the strongest capabilities offered to the local commander will be a persistent platform that can maintain an operational station for months at a time, and perhaps even longer. By the time Project Loon concluded, they had achieved an average flight duration of 161 days. Additionally, near-space assets are payload agnostic and are highly modular. They can be used as either communication relays or ISR platforms featuring a wide variety of sensors and transmitters. While the balloons used by Project Loon were limited to about 260 kilograms of payload, the follow-on airships Project Loon was planning on using would have been capable of lifting upwards of 1,875 kilograms. Propulsion capabilities of the balloons used were around one meter per second, but the plan was to increase that to around 7.8 meters per second, enabling the platform to better maintain station or more quickly reposition to a new area of interest.

The more platforms, or nodes, in the air, the more robust and far-reaching the mesh network. Project Loon demonstrated the ability to maintain a point-to-point mesh network in 2020 of 3,500 kilometers in length. This long reach required 33 balloons, but with a greater payload, such as the airship Loon was developing, the hope was to reduce the number of nodes required by more than half. Airborne tests demonstrated an ability to maintain a 1,000-kilometer backhaul link with only seven balloon nodes. Further testing demonstrated an ability to link two assets over 600 kilometers. Primary communication links were by radio, but Loon had started to experiment with optics that transmit large data loads via light beams. This Loon sub-project was not canceled by Google and lives on today as Project Taara.8 By combining light beam data transmission with a wide presence of connected balloons, warfighters can move large amounts of data throughout the battlespace using jam-resistant, low-signature methods.

The DOD is already deploying the SkySat radio repeater, and expanding the balloon platform to include ISR capabilities, but these applications appear limited to ground operations.9 This system extends the standard two-way radio link from 10 miles to 500 miles and has been used by the Marine Corps in forward areas. As a starting point, the Navy can leverage these existing systems to explore the possibilities for future navalized balloon capability. 

Marines with the 26th Marine Expeditionary Unit’s command element prepare to launch a lofted communications balloon from the port side elevator of USS Kearsarge, Oct. 15, 2010. (Photo via U.S. National Archives)


When discussing near-space assets, some have mentioned the “giggle factor” whenever anyone brings up the idea of using balloons for military objectives. Any objective review of stratospheric balloon capabilities would quickly see how robust these platforms are and their great potential for military applications. Traditional conceptions of what military capability “ought” to look like must give way to more nuanced visions of what is possible amidst the evolving technological landscape. In the case of stratospheric balloons, the capability is already quite mature and ripe for exploitation.

Mark Howard is a retired Navy Commander who spent his time as an electronic countermeasures officer and is a graduate of the Naval War College.


1. Clark, Bryan and Walton, Timothy; Taking Back the Seas Transforming the U.S. Surface Fleet for Decision-Centric Warfare, Published by CSBA 2019.

2. Article published by NAVSEA accessed June 2, 2023:

3. Lundquist, Edward, Tactical Sea-Air-Shore Communications – Network Effectiveness and Survivability needs more nodes, Published by Mönch Verlagsgesellschaft mbH, Naval Forces III-IV/2020, Page 40.

4. Bordetsky, Alexander; Benson,Stephen; and Hughes, Wayne, Mesh Networks in Littoral Operations, Published by US Naval Institute Blog, May 12, 2016.

5. Tomme, Edward, The Paradigm Shift to Effects-Based Space: Near-Space as a Combat Space Effects Enabler, Research Paper No. 2005-01 (Maxwell AFB, AL: Air University, 2005), available at <https://apps.>.

6. ibid.

7. Project Loon records published by Google, accessed Jun 2, 2023, <>.

8. Project Taara overview published by Google, accessed Jun 2, 2023, <>.

9. Von Ehrenfried, Manfred; Stratosheric Balloons – Science and Commerce at the Edge of Space, Published by Springer Praxis Publishing, Chichester, UK 1st ed. 2021.

Featured Image: A high-altitude balloon carrying HySICS instruments to the outermost part of Earth’s atmosphere is inflated with helium at sunrise on the morning of Sept. 29, 2013. (NASA photo via HySICS Team/LASP)

Procuring Modular Containerships for Flexible and Affordable Capability

Pitch Your Capability Topic Week

By Tyler Totten

The U.S. Navy should pursue commercial containerships and compatible containerized mission systems. These ships and systems will allow the U.S. Navy to rapidly field new technologies, expand the maritime industrial base, grow the ranks of experienced seafarers, and provide surge capacity in times of national need. Containerships, as well as combination containership/roll-on roll-off vessels (ConRo), would allow the U.S. Navy to affordably procure a large number of hulls compared to typical naval warships, and open options to augment a range of missions. These ships would allow conventional combatants to focus their high-end capabilities on the highest priority missions, while augmenting many of their capabilities with containerized support. Containerships can act as valuable force multipliers and retain a significant amount of modularity in a time when conventional naval force structure is at risk of falling behind the rapidly evolving state of capability.

Containership Capabilities and Modularity

Because even a relatively large mission payload would still be a small fraction of a containership’s capacity, there would be plenty of space for systems that feature typically inefficient form factors. Relieved of the need for the most optimal and efficient space and weight arrangements, there are options for affordability and capability that might otherwise be challenging on a conventional combatant where weight, volume, and complexity are highly constrained and deeply embedded into the hull design.

Containerized systems would not necessarily be restricted to a single standard size so long as they utilize standard interfaces. The ability to vary from specific limits and how commercial containerships are not as weight limited as conventional warships are important distinctions from the mission module approach of the Littoral Combat Ships (LCS). With the LCS program, the design was driven in a direction that did not allow for wide variance in module sizes without significant impacts to performance. By comparison, a commercial containership such as the U.S.-built Aloha-class can carry nearly 200, 40-foot containers in a single layer on deck, representing an area equivalent to more than four Independence-class LCS mission bays.1,2 Given deep container holds below deck, additional space between containers, and the ability to stack containers, the actual usable space is even greater.

Utilizing containerships to carry weapons, sensors, and other payloads provides for unique mission capabilities. Drop-in modules with integrated hatch covers could replace the standard container bay covers, and allow containerships to hold MK41 VLS tubes. Deck-mounted launchers for Naval Strike Missiles (NSM), Harpoon, and others could be mounted using standard interfaces. Similarly, SeaRAM, RAM, MK38 25mm guns, minelaying equipment, and other weapons stations could be deployed. And simply offering a large amount of seaborne flattop space could allow for conventional ground systems to be fired from the deck, such as missile artillery systems, Patriot batteries, NMESIS launchers, and the Army’s forthcoming SM-6 and Tomahawk launchers.3,4

The High Mobility Artillery Rocket System (HIMARS) is fired from the flight deck of San Antonio-class amphibious transport dock ship USS Anchorage (LPD 23) during Dawn Blitz 2017. (U.S. Navy photo by Mass Communication Specialist 2nd Class Matthew Dickinson)

Power and cooling would be provided by onboard interfaces, with the aforementioned Aloha class having ~8 MW of installed generation. Further augmentation could be provided on an as-needed basis by containerized generators and cooling units that would be cited near their users. Such units are readily available on the commercial market. Where systems require particular power quality or voltages, specific interface equipment would be incorporated.

In additional to weapon systems, any components that were built with compatible interfaces could be fielded. An obvious option would be sensors such as mobile radars or containerized versions of shipboard systems. With the large holds available and the typically sizeable tankage capacity of commercial containerships, underway replenishment gear could also be carried and the ships could augment the existing logistics force ships. There would also be potential to procure geared containerships, such as those with their own cranes, to allow for self-unloading, or facilitate the containership as an at-sea transfer point for other ships in permissive seas. These cranes could be designed-but-not-fitted in a practice already utilized in the commercial industry to allow conversion between ungeared and geared containerships. Those cranes, or other mission loadout cranes, could provide for VLS and other resupply not possible with the present Combat Logistics Force. For any ConRo ships purchased, these could augment the existing Roll-on/Roll-off (RoRo) ships in DOD inventory. This would potentially include making use of existing cargos and capabilities of those ships such as the Modular Causeway System (MCS) for establishing links to the beach in areas without developed port facilities.

Potential modular capabilities for containerships. (Author graphic)

Another usage would be as motherships for manned and unmanned aviation and small boats, with aircraft-rated containers allowing for the deployment of a large number of small UAVs or rotary aviation. Given the hundreds of tons of containers routinely loaded onto container hatch covers, this would not be a challenging design. The interior holds would provide further space for fuel while munitions, spares, and workshops could be provided on the deck. For larger unmanned assets, such as LUSV and MUSV, these ships could serve as at-sea service stations and as command nodes in certain areas.

The interior holds of a containership. (Photo via Wikimedia Commons)

Containerships could also make major contributions toward deception and challenging adversary decision-making. The usage of chaff, flares, decoy dispensers, and radar reflectors could be utilized to not only reduce the likelihood of a hit, but to also confuse opposing scouting efforts and complicate the battlespace with more signatures. Conventional warships typically field relatively few decoy dispensers, and a single containership deploying numerous decoys could make a major difference in shaping the electromagnetic footprint of a force on a theater-wide level. Furthermore, the suspected presence of these ships and their significant modularity could force adversaries to dedicate greater time to scouting and analysis in an attempt to understand the capability and operational roles of the containerships.


Aside from the modules, the platforms would not be designed to military standards given how the added costs and complexity would negatively impact affordability. Containerships would not offer a highly survivable asset and would not be one-for-one replacements for conventional combatants. They would not be suitable for independent operations in high-threat environments and would not be able to keep up with carrier groups executing fast transits. They would not be suitable for surface action groups and formations that prioritized sustained speed, including actions deep within hostile Anti-Access/Area Denial (A2AD) zones. These should be acceptable tradeoffs for these ships given their cost and roles.

Instead, these ships would be used in concert with conventional combatants, often in rear areas, or in ways to minimize their likelihood of being engaged. More risky missions could be undertaken when required and may even be desirable in situations where other slower or vulnerable ships were included in the formation. This could include some U.S. and allied amphibious forces, auxiliaries, and even tankers and supply ships operating in support of particular operations. These ships could also provide support to forces operating in adjacent higher-threat areas, where those forces could provide targeting to containerships to leverage their magazine depth and long-range fires.

The ship would not be expected to fight through a hit, particularly against purpose-built anti-ship missiles or torpedoes. However, the containership’s sheer mass would provide a degree of resilience even without shock grade systems and conventional warship damage control capability. This would particularly be true if the hold space without mission equipment was filled with empty containers. The sheer size of the ship would on its own likely provide a degree of resilience, especially against smaller warheads such as the YJ-83 or similar weapons. These small warheads have proven to be relatively effective in achieving mission kills against small combatants, but multiple hits are likely required against larger ships. The flexible configuration of containerships will challenge the ability of advanced missiles to employ aimpoint selection capability to maximize lethal effect, which is much easier against conventional warships with the unchanging locations of their critical spaces, such as magazines and launch cells. Even if a mission kill is suffered, the prevention of total ship loss may allow for undamaged modular combat systems to be salvaged and retrieved. Equivalent systems may have otherwise been lost on conventional warships, whose combat systems are deeply integrated into their hulls.

The container ship MV Hyundai Fortune the ship Hyundai Fortune burns March 21, 2006 in the Gulf of Aden, approximately 43 miles off the coast of Yemen. (Photo via Wikimedia Commons)

Weapons targeted at naval formations featuring these containerships may be drawn toward the larger vessels, which enhances the survivability of the conventional warships that would suffer greater casualties and losses of capability from taking hits. Containership crew safety could be increased by utilizing armored command modules that serve as protected locations to command the ship. Containerships could feature multiple command modules to offer redundancy and resilience. Armored crew modules would not work for every mission set, such as flight operations where deck crews would be needed at times, but would allow for a degree of safety during an attack.


The U.S. shipbuilding industrial base has shrunk greatly since its peak in World War II. The remaining yards have operated in a constrained environment for years but still produce ships for the Jones Act market, even if they do not have the ability to compete with the likes of South Korea, Japan, or China on total tonnage. While their costs are greater than foreign yards, a U.S.-built containership is still considerably more affordable than military ships.

The two-ship Aloha class was ordered from Philly Shipyard (formerly the Aker Philadelphia Shipyard) for $418 million in 2013 (around $512m in 2022 dollars), representing a unit cost of around $250 million. Matson paid a similar amount for their two Kanaloa-class ConRo ships from General Dynamics NASSCO, which entered service starting in 2020.5 If purchased in sufficient numbers, a containership or ConRo unit cost could be even less. Matson placed a 2022 order for three additional Aloha-class ships for $1 billion, an average unit price of about $333 million.6 By comparison, the FY10 LCS block buy featured a unit cost of about $440 million (or $590 in 2022 dollars).7 FFG 62 frigates are expected to cost about $1.1 billion per ship, LPD 17 Flight II ships are estimated at about $1.9 billion, and T-AO 205 oilers at about $680 million.8, 9, 10

Procurement of these containerships would not necessarily be intended as an alternative to current planned battle force procurements. Resource balancing will inevitably require budgetary trades as any Navy acquisition dollars spent on containerships would invariably impact potential spending on additional combatants. That said, there are industrial base limitations and only so many destroyers, frigates, and amphibious ships can be ordered per year on a sustained basis in the near-term.11

Containerships could be procured outside the traditional warship shipbuilding industrial base and offer opportunities. Adding containership production would be more affordable and adds production in currently underutilized domestic shipyards. Philly Shipyard’s only current government shipbuilding project is the replacement maritime academy training ships, National Security Multi-Mission Vessels (NSMV), via Tote Services.12 The first two vessels are being procured for about $315 million. Smaller shipbuilders that would struggle to produce a conventional warship would potentially be competitive for containerships contracts. Furthermore, mission packages could be competitively awarded separately from containership procurement.

If about $500 million per year was made available on a sustained basis, the Navy could likely order two containerships annually, not accounting for lead ship, mission module, and initial program stand-up costs. Since the program would utilize a relatively simple commercial design and leverage industry standards, the design would not require commonality when built at multiple yards. Of course, components such as main engines and generators would be advantageous to be common across all purchases. Study and analysis would be required to identify if the cost to acquire a common design can be offset by commonality savings.

Assuming a procurement rate of two ships per year, the Navy could have operational ships within five years from first delivery. The Navy could additionally purchase or lease used containerships to begin experimentation immediately while standing up the program. A steady ship order volume would also provide for improved stability of the commercial industrial base, lower unit costs, and potentially stimulate additional orders as costs decrease and expertise improves. Further positive impacts to the overall shipbuilding industrial base, to include military production, may also result from increased supplier stability and demand. Derivative hulls could also be explored as the basis for other auxiliary ships.

As the Navy grows its containership inventory and develops experience, many non-military containerships could be leveraged for operations and provide a vital source of surge capacity if needed. This could include wartime purchases of idle containerships and using already built mission systems.

As capabilities are upgraded, exchanged for new systems, or made obsolete, they would not require taking the ship itself out of service. A 30-year-old MK41 VLS or a 10-year-old radar might not be advisable to transfer and permanently install in a newer combatant with its full service life still ahead of it. The short-term nature of installing modular systems onto containerships would allow maximum service life to be extracted from the modular systems irrespective of the hulls they are installed on.

Personnel Configurations

The operating profile for these containerships could broadly follow several approaches: Navy-operated with uniformed sailors, Military Sealift Command (MSC) contract mariners, and through a ship-as-a-reservist approach. Balancing these approaches would require experimentation of how to best integrate them into the force.

The first approach would be the same as with current auxiliaries. The ships would be operated by the government and move government cargos. They may or may not carry weapons or sensors in this role, but could be loaded with such systems when desired for operations or exercises. When carrying weapon systems, Navy crews come aboard to operate. This approach would allow more permanent ship changes, including installing sensitive C4I systems, as the ships could remain under constant direct government control.

An alternative approach would be to employ a ship-as-a-reservist role where the containerships would be U.S.-flagged and operated commercially. The operating company could receive these ships at a discount in exchange for an agreement that they be provided in the event of national need and for a set number of regular training and experimentation periods. There may be value in Congressional action to approve a special approach under the Federal Ship Financing Program (Title XI) or through a new bill to reflect the outlined operational approaches.13 This would differ from typical subsidized purchases in that the ships would be expected to be used by the Navy on a semi-regular basis for exercises and other operations. In this approach, the shipping company would be responsible for most of the normal operating costs, while having benefited from a greatly reduced capital investment. The Navy would carry some or all of the cost of acquiring the ship and may award a fee to the operating company for use of the ship during the agreed upon periods each year to offset the lost revenue. Notionally, if the ship was activated for a few months every year or two, the Navy would be able to utilize these ships for various operations at a minimal cost compared with traditional auxiliaries.

Crewing these ships under the ship-as-a-reservist method could be handled several ways. One such method that may entice additional mariners and address a mariner shortfall would be to create a special reservist force. During normal times, these crew would operate the containerships in commercial service. When activated, some of the crew would also be activated as reservists. As part of this special service, they could be excluded from regular reservist status and only serve aboard the containerships. The option to allow them to focus on operating these ships without committing to the full scope of naval reservist status could be useful for recruitment and retainment. Specialists for sensor, weapon, and other modular systems would likely still be required, but this approach could provide crew fully qualified on shipboard systems without an extensive Navy training pipeline. The crewing approach would be evaluated and adapted to optimize it with additional operational experience and force structure integration as needed.


The Navy should add capacity, capability, and improved flexibility by pursuing containerships. They would provide direct mission support, combat logistics support, and more rapid testing of new systems and technologies. Given the nature of these ships, striking an appropriate balance of capability without concentrating too much valuable hardware on a single ship would be important to identify through analysis and wargaming. But these ships would certainly add hulls in an accelerated timescale while improving U.S. domestic shipbuilding capacity, compared to ramping up conventional warship production within the tight limits of the industrial base. Pursuing containerships would leverage underutilized capacity at a fraction of typical combatant costs and deliver a unique capability on a timescale unmatched by most other options.

Tyler Totten is a naval engineer supporting Navy ship programs including EPF, LCS, and DDG(X), with a deep interest in international and specifically maritime security. He is also an amatuer science fiction writer published on Kindle. He holds a B.S from Webb Institute in Naval Architecture and Marine Engineering. He can be found on Twitter at @AzureSentry.


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2. Independence class Littoral Combat Ship – LCS. (2022). Retrieved from

3. Martin, L. (2022, December 5). Retrieved from Lockheed Martin:

4. Fabey, M., & Roque, A. (2022, April 20). Retrieved from Janes:

5. Schuler, M. (2020, January 06). Matson Takes Delivery of First Kanaloa-Class ConRo. Retrieved from gCaptain:

6. Matson. (2022, November 02). Matson to Add Three LNG-Powered Aloha Class Containerships. Retrieved from PR Newswire:,hallmark%20%E2%80%93%20timely%20delivery%20of%20goods.

7. USN. (2011, January 05). Littoral Combat Ship (LCS) contract award announced. Retrieved from The Flagship:

8. O’Rourke, R. (2022). Navy Constellation (FFG-62) Class Frigate Program. Washington DC: Congressional Research Service.

9. (O’Rourke, Navy LPD-17 Flight II and LHA Amphibious Ship Programs: Background and Issues for Congress, 2022.

10. (O’Rourke, Navy John Lewis (TAO-205) Class Oiler Shipbuilding Program: Background and Issues for Congress, 2022)

11. Shelbourne, M., & LaGrone, S. (2023, January 10). CNO Gilday to Shipbuilders: ‘Pick Up the Pace’. Retrieved from USNI News:

12. Philly Shipyard. (2022). Government Projects – National Security Multi-Mission Vessel (NSMV). Retrieved from

13. US DOT Maritime Administration. (2022, June 23). Federal Ship Financing Progrm Title XI). Retrieved from Maritime Administration:

Featured Image: An A13-class container ship. (Photo via Wikimedia Commons)

Pitch Your Capability Topic Week Kicks Off on CIMSEC

By Dmitry Filipoff

This week CIMSEC will be running articles submitted in response to our call for articles on pitching novel capability ideas.

The technological landscape is offering more opportunity than ever before to innovate with disruptive new capabilities. As legacy systems wane in relevance, militaries must rigorously explore the art of the possible when it comes to developing new, game-changing tools. As new systems are developed and fielded, wide-ranging changes in the character of war may follow, with geopolitical advantage accruing to the states best positioned to leverage new forms of warfighting.

Below are the articles and authors being featured in this series, which may be updated with further submissions as Pitch Your Capability week unfolds.

Procuring Modular Containerships for Flexible and Affordable Capability,” by Tyler Totten
When the Balloon Goes Up: Naval Mesh Networking with Stratospheric Balloons,” by Mark Howard
The NightTrain: Unmanned Expeditionary Logistics for Sustaining Pacific Operations,” by CDR Todd Greene

Dmitry Filipoff is CIMSEC’s Director of Online Content. Contact him at

Featured Image: A U.S. Navy X-47B unmanned combat air system demonstrator aircraft prepares to launch from the flight deck of the aircraft carrier USS Theodore Roosevelt (CVN 71) Nov. 10, 2013, while underway in the Atlantic Ocean. (U.S. Navy photo by Mass Communication Specialist Seaman Kris Lindstrom/Released)