If the Balloon Goes Up

As far back as the early 19th century and the army of Napoleon Bonaparte, lighter-than-air aircraft have contributed to military command, control, communication, intelligence, surveillance, and reconnaissance.¹ Today, they even play a strategic reconnaissance role like that of satellites; Chinese high-altitude spy balloons made headlines around the world in early 2023 doing just that.²

While the utility of lighter-than-air aircraft as sensor platforms is substantial, tethered aerostats also could have significant value as weapon systems, acting as platforms for a variety of kinetic and nonkinetic payloads. Tethered systems can be a valuable deterrent and part of the kill web, at a fraction of the cost of the alternatives. Their simplicity and persistence are unrivaled. By building an integrated aerostat network for battlespace awareness and payload delivery, the joint force can create an asymmetric, simple yet robust, and low-cost kill chain along the first island chain.

The Great Wall of Islands

China’s antiaccess/area-denial (A2/AD) network is well documented.³ In a military conflict with China, that network will make aircraft and ship operations near or inside the first island chain difficult if not impossible. Even reconnaissance and communication satellites will be vulnerable to physical and electronic attack because of their predictable orbits. The joint force can mitigate the challenges by building a counter-A2/AD architecture along the first island chain. Asymmetric capabilities fielded now will project power in the Pacific, aid in building a common tactical picture for U.S. and partner forces, complicate the battlespace for adversaries, and close the kill chain if open conflict comes. Employed appropriately during the competition phase, however, these capabilities could even promote deterrence, allowing disputes to be handled politically rather than militarily.

The geography of the region can help.⁴ Generally speaking, viewed north up, maps of the first and second island chains can look more like a barrier to China than a barrier for China. Looking at it from another perspective—as if toward the Pacific from China’s eastern mainland—the first and second island chains now appear to constrain China’s access to the Pacific. From this point-of-view, the chain of islands formed by Japan, the Philippines, Malaysia, and Indonesia creates conditions for a U.S. joint force A2/AD infrastructure of its own, restricting China’s ability to operate off its eastern shore.

The central idea—using geography to the joint force’s advantage—is not novel. It is an essential premise of the Marine Corps’ expeditionary advanced base operations concept, in which the inside “stand-in forces” along the first island chain deter a hot conflict while being supported by a larger force held in reserve. If violence cannot be deterred, mass combat power could flood the battlespace supported by the antiship capabilities of the stand-in forces.⁵

The first and second island chains’ dispersed islands, reefs, and other regional geographic features lend themselves to the creation of a broad set of asymmetric warfare capabilities enabled by aerostats, just as they do for small, mobile Marine expeditionary advanced bases. The Navy–Marine Corps team can overwhelm the battlespace with advanced sensors, limit its own exposure, induce confusion through asymmetry, complicate decision-making, and deter further conflict, all while enhancing its own situational awareness to build a common tactical picture.

A Kill Mesh

A mesh network of tethered aerostats would be designed to be multispectral, attritable, and capable of connecting to any other sensor or shooter in the domain at any time.⁶ The network would operate at multiple regional and local levels. At the tactical level, aerostats would communicate targetable information to be shared with any forward-deployed unit or system. Through advanced edge computing (processing data as close as possible to where it is obtained) and artificial intelligence, these balloons would be able to collect and analyze large quantities of data locally, minimizing the amount of information transmitted over low-probability-of-intercept datalinks. The network could accept external targetable information or formulate it in-network for use with kinetic and non-kinetic payloads.

Aerostats come in a variety of sizes, capable of carrying physical payloads from 7 to 7,000 pounds, and some can remain aloft for more than 30 days.⁷ They are easily customizable with different payloads and can be fielded rapidly. Unlike aircraft, which require years of operational test and evaluation—often designed around a primary payload—or space-based assets designed to operate for years without maintenance or service, aerostat payloads are simply suspended beneath or within the gaseous hull, connected to the surface by a power source and fiber optic cable for data transmission. The aircraft themselves are state-of-the-art commercial off-the-shelf solutions.

Conceptually, the missions an aerostat can execute are nearly innumerable, but most are not being explored today. Aerostats have a long history of supporting ISR and acting as communication and datalink relays. But more advanced sensors are available: light detection and ranging (LIDAR), for example, which can create high-resolution maps with laser pulses; and acoustic sensors to detect and track underwater vessels. Such sensors collect and process information in real-time, producing images or other output. By integrating advanced machine-learning algorithms, these systems are capable of providing target recognition. In the event of GPS degradation, these systems could operate as fire-control radars to aid in weapon guidance.

As a tool of asymmetry, aerostat networks could be used simply to complicate enemy decision-making just by placing more targets in the battlespace. A communication and datalink relay aerostat (or its surface support vessel/vehicle) could launch swarms of small unmanned aerial vehicles. Used as radiofrequency or electro-magnetic countermeasures, an aerostat’s payload could simply raise the emission-noise floor for a given area of the battlespace to hide or simulate ship locations for adversary sensors. Positioned appropriately, aerostat systems could even assist in personnel recovery after detecting the large infrared bloom from an aircraft’s ejection seat. Moreover, aerostat networks could be used as tactical electronic attack and cyber warfare payload delivery options. Finally, tethered to a surface vessel, aerostats could carry offensive or defensive weapon systems. The modular simplicity of the aerostat is key, as overintegration of the sensor or payload into the system would increase costs significantly, delay fielding, and likely not significantly increase capability or survivability.

Compared with most other aircraft, aerostats are cheap to procure, operate, and maintain. For example, the 420,000 cubic-inch Tethered Aerostat Radar System from Lockheed Martin—presently in service with the U.S. Coast Guard—is one of the largest aerostats, capable of carrying a 2,200-pound payload. It cost $8.9 million in 2016 (roughly $11.25 million in 2023 dollars).⁸ While additional cost can be expected for sensor and autonomous systems, the price is nevertheless an order of magnitude less than the roughly $162 million–plus cost of an MQ-4.⁹ Smaller aerostats can be procured for tens to hundreds of thousands of dollars.

While the joint force is investing in more sophisticated platforms capable of operating in nonpermissive environments from the air, land, sea, and space, these systems are not being procured fast enough or in large enough numbers. In addition, by the time such systems—including the MQ-4C Triton and MQ-8C Fire Scout—are fielded in sufficient numbers, they are sometimes obsolescent.¹⁰ The MQ-4C’s first flight was in 2013; initial operational capability (IOC) for the 68 airframes is finally expected sometime this year (but had not reached it as of this writing). The Navy built 38 MQ-8C Fire Scouts—an unmanned helicopter derived from the civilian Bell 407—and also flew them for the first time in 2013. While Fire Scout IOC occurred in 2019, only 10 are now in operation.¹¹

The joint force continues to invest in small numbers of advanced UASs to support a survivable and robust kill chain. It is commonly held that UASs are expendable in conflict because they are cheaper than manned aircraft to procure and operate, and they do not carry aircrew. But it is unclear whether medium to large UASs will ever truly be expendable. In 2021, the Congressional Budget Office (CBO) found RQ-4 lifecycle costs, which include acquisition and operating costs per flying hour, were only 17 percent less than those of the P-8, the comparable manned platform—$35,200 and $42,300 for the RQ-4 and P-8, respectively.¹² (The MQ-4C is derived from the RQ-4). Also in 2021, the CBO estimated that if the MQ-4C were used for cruise-missile defense in the contiguous United States, 2.8 aircraft would be required to maintain a 24/7 orbit over a given location, compared to just 1.5 aerostats. Operational costs for the Tritons to orbit would be $100–$120 million but only $30–$50 million for an aerostat network, counting military personnel, operation and maintenance, sustaining support, and system improvement.¹³

The CBO’s findings highlight that, while a conventional aircraft can sanitize a much larger volume of airspace in a 24-hour period—assuming the mobile platform does not lose GPS access—the aerostat is better suited for a point-defense mission that could be considered vital in a western Pacific conflict. Take an operational example: If an area of operations had three MQ-4C platforms available, assuming one is operating and one is down for scheduled maintenance, there is relatively little redundancy in the event one aircraft is destroyed. For the equivalent $480 million spent to acquire the three hypothetical MQ-4Cs, perhaps 45 large aerostat systems could have been acquired, with upward of 30 available for tasking.

Look Down, Shoot Down

The role of advanced unmanned aerial systems is to elevate sensors and weapons. Widely deployed aerostats could provide both in much higher numbers—faster, less expensively, and with higher reliability than most other surface, airborne, and space-based systems. Some sensors might be employed from friendly countries an adversary may be reluctant to pull into a conflict, complicating targeting decisions in political as well as numerical ways.

An aerostat network is not a solution to every problem. But as the United States continues to develop kill chains into kill webs, aerostats can enable the rapid fielding of a variety of state-of-the-art sensor and weapon technologies. Fielded in tactically relevant numbers, networked aerostats would provide a robust and affordable way to operate inside the threat’s weapon engagement zone with comparatively simple and risk-worthy platforms.

The network would allow persistent power projection in the western Pacific—a digital blockade of sorts. This would constrain Chinese movements around the first island chain, feed the common operational picture, afford significant offensive and defensive asymmetric capability, and offer tactical payload delivery options if required. The capability is already here, and it will continue to advance. Aerostats will ensure the United States is placing the most capable systems downrange and reducing the continued risks of platform obsolescence.