Read Part 1 on defining distributed maritime operations.
Read Part 2 on anti-ship firepower and U.S. shortfalls.
Read Part 3 on assembling massed fires and modern fleet tactics.
Read Part 4 on weapons depletion and last-ditch salvo dynamics.
Read Part 5 on salvo patterns and maximizing volume of fire. 

By Dmitry Filipoff 

A Combined Arms Framework for Massing Fires

The act of massing fires across forces is inherently a function of combined arms. Individual platforms should be understood in the broader context of the mass firing schemes they fit into, and a mass firing scheme should be understood as a composite integration of multiple platform types. These mutually supporting relationships are not just a matter of adding more missiles to increase the volume of fire. Rather, the different platforms are working together to compensate for each other’s tactical weaknesses and pose combined arms threats that are far more lethal than what the different platforms can pose individually.

By organizing force-multiplying relationships, combined arms warfighting also highlights critical dependencies. Combined arms warfighting often means that one platform type must allow its operational options to be circumscribed by the limits of another platform type, if they are to work together. By understanding how different platform types make allowances to fit together for massed fires, operational behavior can become more predictable, including to the adversary. But behavior can also be more predictable to one’s own forces, which can enhance doctrinal cohesion in this form of warfighting where cross-platform fluency and coordination is especially critical.

Modern warfighting can feature concepts of operation that focus on splitting these relationships apart to gain leverage over the adversary. Defeat in detail is often conceived of as small detachments falling prey to enemy forces, but it can also take the form of homogenous force packages falling prey to an adversary that asymmetrically leveraged a platform-specific weakness that could have been mitigated by a combined arms relationship. By understanding the purpose of these relationships, a force can know how to take advantage of their absence.

It is critical to recognize that the individual platform communities can be their own worse enemy when forming these combined arms relationships. The act of instituting or reforming these relationships can stimulate friction between communities because combined arms warfighting sets the stage for compromises in concepts of operation and time-consuming cross-community force development. Historically, combined arms debates have sometimes yielded community “purists” who are resistant to cross-community integration. These purists tend to strongly believe in the self-sufficiency of their own community’s capability, and their proposed combined arms concepts of operation often take the form of assigning spheres of activity to the communities that are operationally complimentary but tactically separate.¹

The aforementioned need to circumscribe options according to the limits of a different platform type can cause different communities to view each other as a drag or a nuisance rather than a force multiplier. A naval aviator may be loathe to limit their scope of maneuver so they can provide local sea-skimming air defense and sensory coverage for a much slower warship. A warship may be loathe to delegate release authority for weapons in its deep magazine to an aviator flying above, who may be better able to cue and direct long-range fires. Yet these relationships can be a core operational necessity that must be ironed out in combined force development. The current U.S. Navy construct of having carrier air wings conduct deep strikes while surface warships conduct what amounts to a goal line defense against air and undersea threats is a more divided method of warfighting than a truly integrated combined arms relationship. The fact that genuine integrated training and exercising is a very small fraction of the workup cycle compared to community-specific training is reinforcing this construct.²

The challenge of community purists may be encouraged by the breadth of multi-mission capability that already exists within the individual naval communities, especially in U.S. naval aviation and surface forces. In the absence of such multi-mission capability, the need to join specialized forces into integrated force packages would be more clear. But the multi-mission capability that is organic to these naval communities cannot mitigate many of their fundamental platform weaknesses, or the fundamental need for a revamped combined arms relationship that is geared toward launching and withstanding massed fires.

A framework can be established to help understand the strengths and weaknesses of the various platform types as they relate to massed fires, and understand each platform’s unique contribution to the combined arms team. This framework can shed light on how the overall scheme of massed fires can shift and reorganize when a certain platform type cannot contribute due to operational circumstance or lack of capability. This framework can also be used to understand platform traits in isolation to understand key factors of resilience. Understanding the organic capabilities of an individual type of platform can shed light on that platform’s potential for standalone fires, last-ditch salvos, and the usefulness of homogenous force packages. It can also shed light on how these platforms could be taken advantage of when they are cut off from the broader combined arms team. Understanding these capabilities in isolation offers a glimpse into how much effectiveness may be retained if a distributed force fractures into individual force concentrations and units.

Relevant platform traits include but are not limited to: magazine depth, on-station endurance, organic sensing, reload speed, ability to gain proximity to warship targets, and maneuver speed. Each platform’s set of advantages bolsters an overall mass firing scheme in certain respects, while each platform’s disadvantages may be compensated for by other platforms, and possibly circumscribing their behavior in the process.

Magazine depth is how much volume of fire can be fielded on a single platform. Higher magazine depth allows a platform to preserve force distribution for longer, because it can contribute many rounds of small salvos while still remaining on station. If a platform is isolated or under duress, high magazine depth allows the platform to contribute a substantial volume of fire in standalone or last-ditch salvos. Shallower magazine depth translates into higher frequency of reloads during the duration of a conflict, which disrupts force distribution. Shallow magazine depth also results in last-ditch and standalone salvos featuring small volumes of fire that are less likely to be overwhelming.

On-Station Endurance is how long the platform can stay on station as a function of its unrefueled range. The longer a platform can remain on station, the longer it offers options for contributing fires, and the longer it preserves force distribution. Low endurance diminishes the availability of fires and how much a platform can contribute to a distributed force posture. 

Organic sensing is how much targeting information a platform can gain through its onboard sensors alone. A high degree of organic sensing better allows a platform to target its own fires directly and manage a killchain that is less distributed across multiple authorities. High organic sensing can also allow a platform to cue the long-range fires of other platforms, if it can reliably deliver its sensor information to a broader network. Low organic sensing makes a platform much more dependent on outside sources of information to target its long-range fires. In the context of standalone or last-ditch salvos, organic sensing capability can help make those fires more accurate, and better preserve the resilience of the platform if it must continue the fight without a network. 

Maneuver Speed. Maneuver speed is how fast a platform can travel. High maneuver speed allows a platform to more flexibly fit into mass firing sequences and manage the risks of emissions. Higher speed can allow platforms to concentrate in larger numbers in shorter timeframes than slower platforms. 

Ability to Gain Proximity to a Warship Target allows a platform to build more resilience into a firing sequence. The more proximity a platform can gain, the more it can add to fires launched on short notice. Closer proximity translates into a better ability to insure a firing sequence against attrited fires, preemptively destroyed archers, and improve the distribution of launches across the duration of the firing sequence.

Reload Speed is how quickly a depleted platform can be rearmed and returned to the fight. Faster reload speed preserves force distribution and the availability of fires. A high reload speed as described here means it takes a platform longer to reload. Reload speed is also understood here as a function of maneuver speed rather than magazine depth, where the transit time is usually longer than the reload time. The availability of fires is not only a matter of how fast a platform can be reloaded with new weapons, but how fast the platform can travel between its weapon stocks and its launch areas.

Each platform features some combination of these traits, and a combined arms framework would seek to cover the weaknesses while maximizing the strengths. These advantages and disadvantages illuminate what circumstances constitute favorable terms for launching fires for each platform and their broader operational options. If a platform must shoulder a disproportionate burden of contributing fires, then the effectiveness of the overall mass firing sequence may be defined by that platform’s strengths and weaknesses, and offer an adversary disruptive points of leverage. 

The Uneven Nature of Massed Fires and Anti-Ship Combined Arms Teams 

These concepts of massed fires have principally focused on organizing forces for anti-ship strikes, and these concepts are by no means a complete conception of combined arms naval warfighting. But the act of striking warships is a challenging priority objective that demands combined arms methods. Aside from managing weakness and earning force multiplying advantages, combined arms methods are compelled by the need to muster the significant volume of fire required to breach the especially dense defenses of warships. Organizing for anti-ship strikes can therefore yield combined arms methods that bring together multiple communities for the sake of targeting a single type of platform.

This results in critical asymmetries in how platforms can come together to mass fires, and how competing schemes of massed fires can interact during combat when one side has an advantage in anti-ship fires. When a massed firing scheme is deprived of its surface force, or its surface force is substantially outranged by the opposition, then the resulting asymmetry becomes especially risky to manage.

While warships can be fired upon by multiple platform types, anti-ship missiles cannot threaten many of those platform types in return. These include aircraft, submarines, and land-based forces. Platforms such as aircraft and submarines are only threatened by weapons that have much shorter ranges than anti-ship weapons, challenging the ability of defending warships to threaten these archers before they fire arrows. Certain platforms have a superior ability to fire effectively first against warships because their survivability is not governed by the same dynamics as symmetrical surface-on-surface engagements.

Yet platforms that cannot be threatened by anti-ship weapons usually face critical disadvantages in on-station endurance and magazine depth, with bombers being somewhat of an exception. These factors are the strengths of surface platforms, allowing them to compensate for the shortfalls of aircraft and submarines, who in turn compensate for the surface forces’ disadvantages in rapid near-term maneuver and ability to gain proximity to an adversary. Surface forces can undergird a scheme of massed fires by being able to bring significant missile capacity forward and maintain it there, unlike most other platform types. Therefore the function of surface forces in the combined arms team is to provide a deep and persistent base of fire for a mass firing scheme, which augments the forces with shallower magazines and more transient presence. By leveraging this base of fire, those other platform types are spared from having to heavily concentrate their platforms, manage the ensuing logistical challenges, and take greater risks. Other platforms and domains can certainly serve as a base of fire for a mass firing scheme if they have the numbers and logistics to do so. But even so, the mass firing scheme is still oriented on launching strikes against warships, and combining multiple communities to take out a critical member of the opposition’s combined arms team.

The base of fire offered by a surface force can have its own scope of maneuver limited by the critical roles of the other platform types. A surface force that ventures beyond the range of land-based aviation will be deprived of one of its most valuable partners in massing fires. Perhaps even more importantly, it will be deprived of the partner that can provide critical air defense coverage for both offensive and defensive purposes. Aviation will be needed to inflict major attrition against sea-skimming salvos well before they break over the horizon view of warships. The adversary can reciprocate this of course, creating a requirement for aviation to provide forward air defense coverage to friendly salvos on their way to the target. Aviation can also reload anti-air weapons much faster than warships, helping warships persist in providing a maneuvering base of offensive fire, rather than having warships be forced to withdraw with unused offensive weapons due to depleted defenses.

A surface force should therefore be keen to stay well within the range of friendly land-based aviation to be able to substantially grow and withstand volumes of fire. Carrier aviation can certainly provide these capabilities, but typically not to the same scale and range as land-based aviation. Carriers can provide valuable aerial support in deep oceanic areas that land-based aviation may struggle to reach or loiter for long. But overall, in a scheme of massed fires, it may be wise to ensure that the base of fire provided by a surface force is adequately overlayed by the base of air defense coverage provided by aviation.

When two schemes of massed fires are competing and interacting during combat, the ability for one force to substantially outrange the anti-ship firepower of the other can have a profound effect on how advantage develops between adversaries. If a force can effectively target enough anti-ship fires to a much longer range than the opposition, then the opposition’s firing scheme may be deprived of the valuable base of fire their surface forces offer. This deeply affects the resulting scheme of massed fires because it splits apart combined arms relationships.

When a force’s scheme of mass fires is substantially outranged by the opponent, then the force can have to heavily focus its aviation on defending its surface forces while the opponent leverages their superior ability to fire first. As waves of massed fires are launched from distant standoff ranges, aviation would need to heavily focus on attriting the incoming volume of fire. The goal would be to inflict enough depletion on the adversary that their ability to follow up on their anti-ship attacks would be diminished, and that one’s remaining strike options would be meaningfully preserved via the surviving surface forces, which have more freedom of action against a heavily depleted adversary.

Because aviation has a natural advantage in both its speed and ability to fire first against warships, aviation would be pressed to reach far out and attack warships before they can launch their longer-ranged firepower against one’s own surface forces. At these extended ranges, aviation is more likely to be acting alone in mustering the volume of fire instead of as part of a combined arms team. Aviation would have to muster significant numbers and aerial tanking to field enough volume of fire, and then have to assemble aircraft into especially dense concentrations around targets to launch timely strikes. On top of this requirement, aviation may be required to make major contributions to fleet air defense as mentioned. Longer-ranged anti-ship firepower therefore forces the opposition’s aviation to shoulder much more of both the offensive and defensive burden, causing aviation to bear outsized responsibility on the combined arms team.

But aviation may not have to be alone in this scenario. When the anti-ship firepower of a surface force is outranged, the combined arms team can still consist of aircraft and submarines, who are both able to bypass anti-ship firepower through their respective domains and earn closer proximity to an adversary. If enough aircraft and submarines can work together to combine fires at the forward edge of the battlespace, then they may be able to strike effectively first against surface forces before they can launch standoff fires against warships.

In similar fashion, the combined arms team in an A2/AD zone can consist of submarines and stand-in forces because of their shared ability to persist deep within a battlespace. While both of these forces may be constrained by their magazine depth, their ability to gain proximity to the adversary can give them opportunities to threaten warships with fuller magazines, and in areas where launching a last-ditch salvo from a warship would be futile.

Different operational circumstances will yield different combinations of combined arms teams. Some platform types may face circumstances that make their ability to contribute fires prohibitive. This can force other platforms to increase the proportion of their contribution to a mass firing scheme, but with the chance of increased risk, and possibly because their platform weaknesses cannot be as effectively compensated for by others. If a distributed force fractures into smaller and individual elements, they would be well-served by seeking out friendly platforms and forming ad hoc combined arms teams to the extent possible. It is critical to consider how to maximize combined arms relationships in a variety of operational circumstances, and to understand how to split apart these relationships for an adversary.

Rapid and Last-Ditch Fires

A key consideration is how different members of the naval combined arms team have widely differing sensitivities to last-ditch firing pressures. This heavily affects the ability of the broader force to leverage the last-ditch salvos of certain platforms with additional fires. These dynamics shape the ability of a force to maintain its resilience and mass firing capability while incurring losses.

Assuming a force has quality situational awareness over a wide area and sea-skimming surfaces, a warship that is under fire from a salvo can have tens of minutes of warning, because that can be the time-to-target of the incoming salvo. This can give the warship a decent window of time to discharge its last-ditch fires, and give the broader distributed force more time to organize contributing fires to leverage the forthcoming last-ditch salvo.

Early warning and last-ditch salvos are different for aircraft and submarines in critical respects. The weapons that threaten these platforms, such as anti-air missiles and torpedoes, have a small fraction of the time-to-target of anti-ship missiles can take tens of minutes to reach a warship. Yet the maneuvering speed of aircraft and submarines is much closer to those weapons compared to the speed differential between warships and anti-ship missiles, where evasive maneuvering is a much more viable method for improving the survivability of aircraft and submarines during the transit of the incoming weapon. But this potentially radical maneuvering can inhibit the ability of those platforms to discharge their salvos in last-ditch fires, where launching those fires could require a steadier movement profile that drastically increases the incoming weapon’s chances of striking the platform. Even if they opted to fire last-ditch fires in reaction, the act of discharging the final salvo may take longer than how long it takes the weapon to reach the submarine or aircraft, unlike in a warship’s situation. Unlike long-range anti-ship fires, the broader distributed force would have virtually no time to organize contributing fires in reaction to anti-air or torpedo attacks.

Compared to anti-ship fires, the kill chains of anti-air and anti-submarine fires may be more easily completed by individual platforms, who will often have sufficient organic sensing and magazine depth. A single fighter with its onboard radar and several anti-air missiles is enough to threaten a bomber, or a frigate with its sonar and several torpedoes can be sufficient to threaten a nearby submarine. The proximate nature of these engagements allows a single platform to satisfy their information needs with organic sensors, and the offensive-defensive balance of these engagements requires far fewer weapons to muster enough volume of fire. By comparison, a warship that needs to be targeted hundreds of miles away and requires dozens of missiles to overwhelm can demand a broader information architecture and carefully coordinated fires from multiple force packages. It takes far less capability to put aircraft and submarines into a position where they feel forced to discharge last-ditch fires.

Aircraft and submarines would have to launch last-ditch fires in widely differing circumstances compared to warships. A warship may never detect emissions from the vast majority of distributed platforms that have launched fires against it. But aircraft and submarines can use their organic sensors to detect the organic sensors of the platforms that are targeting them. A bomber can sense illumination by an incoming fighter, or a submarine may get pinged by a warship’s active sonar. Aircraft and submarines would not wait for anti-air missiles and torpedoes to be on their way to then react with last-ditch fires. Instead, they depend more heavily on interpreting the intent behind emissions and sensing to have enough early warning to launch last-ditch fires and then take defensive measures. Rather than reacting to incoming weapons, they need to sense the platforms that could launch the weapons, which makes them much more sensitive to last-ditch firing dynamics and pressures that can force them to waste munitions.

An opposing fighter squadron that simply vectors toward a group of bombers and illuminates it with radar can be enough to trigger last-ditch fires from those bombers, without the fighters having to expend any weapons of their own. By comparison, a warship that knows it is being targeted, or even under attack by incoming fires, can still hold off on launching last-ditch salvos. This is because a warship can be confident that the incoming volume of fire is not enough to overwhelm its defenses, a factor that is mostly absent from the survivability considerations of aircraft and submarines. A warship’s dense defenses allows it to limit the circumstances that prompt its last-ditch fires to reacting to arrows instead of archers. The existence of launched arrows more reliably indicates the adversary’s intent to strike a target, making warships harder to provoke into last-ditch fires with simpler posturing and active sensing.

Overall, a distributed force can include a variety of platforms, whose different traits and capabilities must be combined for operational effect. As commanders consider how to employ a distributed force in a contested battlespace, they must understand the strengths and weaknesses of individual platform types and how this shapes their options. The following platform breakdowns discuss their individual traits and how they relate to naval salvo combat and mass fires more generally.

Surface Warships

Surface warships embody the ability of navies to efficiently bring mass firepower to sea. Blue water navies field a significant amount of their conventional cruise missile firepower in their surface fleets, with launch cells numbering in the thousands for the most powerful nations.³ Some of the most critical capabilities surface fleets offer are their considerable numbers, endurance, and missile capacity, which are central attributes for massing fires and distributing forces.

Despite their considerable strengths, surface ships suffer from long reload speeds which harms their endurance in longer timeframes. Their low platform speed increases the challenge of survivability and their ability to mitigate the risks of radiating active emissions. But their high magazine capacity can give their last-ditch fires substantial volume of fire, with less of a need for outside fires to bolster their last-ditch salvos into overwhelming dimensions.

The large missile capacity of surface fleets is a double-edged sword. Defensive missile capacity can be used to negate offensive missile capacity, and vice versa. As the number of launch cells increases, the volume of defensive firepower that can be used to block attacks increases as well, thereby raising the amount of offensive firepower needed to overwhelm defenses. The very fact that a surface warship can field a large number of anti-air weapons across its many launch cells can force an opposing warship to empty most of its own magazine in a bid to overwhelm that target. Surface warships can easily empty most of their magazines in the course of launching or defending against a single anti-ship missile salvo.

This strongly contrasts with the combat potential and staying power of other types of platforms. Aircraft, submarines, and tanks can earn relatively high kill ratios against equivalent platforms because there is far less need to salvo their main armaments to achieve lethal effect.⁴ A surface warship may only have enough anti-ship firepower to break through the defenses of a single similarly sized warship, if that. A surface warship can also travel for days and even weeks to enter the fight, only to then expend most of its main armament within a few minutes, and then have to take a long journey back to rearm. Despite the impression of significant capacity, surface warships still heavily depend on combining fires with other forces to limit their depletion and endure in a high-end fight.

No platform’s missile capacity can be effectively understood in isolation from the tactical features of the salvos it may be launching or defending against. An attacking volume of fire can be built across tens of minutes and feature various contributing fires launched from many distributed forces. But when a warship comes under attack by a salvo, the full volume of offensive fire can break over the horizon in a narrow timeframe, while the defending warship must build its own defending volume of fire from scratch within seconds. Because of this dynamic, which will be discussed in more detail in Part 7, there may be some limit to how many vertical launch cells a surface warship can realistically apply to its own defense within the short span of a single engagement. Beyond that limit, additional vertical launch capacity mainly benefits the volume of offensive fires rather than defensive fires. This is partly because surface warships will often have more time to grow the volume of fire when launching an attack compared to defending against one.

The multi-domain nature of modern naval warfighting encourages multi-mission capability and payloads. Modern surface combatants often take the form of multi-mission platforms fielding a variety of domain-specific weapons, and this is partly because they must for survivability’s sake. Submarines, land-based forces, and airborne aircraft are not threatened by anti-ship missiles, but each of these platforms can fire anti-ship missiles against surface warships. For surface warships, there are more threats coming from more domains compared to other naval platforms.

These multi-domain threats pose challenges for configuring the missile capacity of surface warships and limits their true magazine depth. Missile magazine loadouts can be stretched thin across a variety of roles, including anti-ship, anti-air, land-attack, and anti-submarine missions. Each one of these roles can require a large number of weapons for the role to be minimally viable and have enough volume of fire, where weapons can easily crowd out missile cells for other roles. A surface warship with its magazine loadout stretched thin across too many missions may not have enough missiles on hand to credibly launch or defend against a single large anti-ship salvo, creating a dependence on massing fires and combining forces. The challenge of having magazines spread thin at the level of the individual warship can be mitigated by leveraging the broader collective magazine of the distributed force, and configuring magazine loadouts on a force-wide level for distributed fires instead of at the level of the individual platform.

Compared to other missile-firing platforms, surface warships have disadvantages in maneuver, stealth, and susceptibility to attack. The range and speed of modern missiles have greatly diminished the usefulness of warship maneuver at the near-term tactical level. A few minutes or seconds of skilled maneuvering made an important tactical difference in the age of naval gunfights, but modern warships can do relatively little through short-term maneuver to significantly improve their effectiveness against missile salvos, with perhaps the exception of bringing mounted short-range defenses to bear. Maneuver will offer little against missile salvos traveling 15 to 50 times faster than warships, reducing the factors of survivability to defensive capability and deception.

In order to prosecute complex air defense engagements and have broad area situational awareness, surface combatants typically feature powerful sensors that can substantially diminish their stealth. Once these sensors radiate, their unique signatures can provide enough information to help localize and classify the warship at long range, potentially to several hundred miles.⁵ The usefulness of this information for targeting anti-ship attacks can last for a significant period of time given how long it would take a slow-moving warship to maneuver out of the area it has been localized within. By comparison, an aircraft radiating a signature can use speed and maneuver to quickly put significant distance between its positions, drop below radar horizons, and more effectively manage the risks of emitting.

These high-powered sensors can be employed in defending surface warships against missile attacks, and where missile salvo defense is an especially emissions-intensive form of combat. The ability of these emissions to broadcast the position of the ship could be somewhat mitigated by the short-ranged nature of fighting off sea-skimming missiles breaking over the nearby horizon. But if a warship wants to use its organic sensors to have early warning of aircraft-launched attacks and have the option of defeating archers before arrows, then it will have to radiate at much longer ranges that can paradoxically draw attackers toward its signature.

Launching an anti-ship missile attack can involve little if any organic emissions from launch platforms because of how the great distances involved create a need for outside cueing. But the salvo itself presents a signature that could be traced back to the launch platform, much in the same way that an air wing’s physical signature could be traced back to a carrier. But unlike aircraft or submarines, surface warships can do relatively little through near-term maneuver to mitigate the near-term risks posed by the signatures of their recently launched cruise missile salvos. They must heavily rely on the range of the missiles and capabilities such as waypointing, retargeting, and missile autonomy to ensure that enough distance and complex threat presentation does not create a footprint leading back to the launching warship.

All platforms can highlight their positions and platform type through emissions and fires. All platforms can emit signatures in the process of employing offensive and defensive tactics. But compared to most other naval platforms, surface ships cannot as effectively mitigate risk through maneuver, and surface ships can be fired upon from a wider variety of platforms and domains. In a great power navy, surface ships compensate for their higher susceptibility to attack by featuring high numbers and especially dense defensive capability.

Submarines

Submarines offer unique advantages in the distributed fight. But their ability to launch useful salvos is heavily constrained by their limited missile capacity and volume of fire, as well as the challenges of undersea communication. Where submarines offer advantage to mass fires is primarily through their ability to gain proximity and the highly favorable tradeoffs of sinking ships with torpedoes instead of missiles.

Submarines are poorly suited for contributing to mass fires in a variety of respects, due to their combination of low magazine depth, long reload speed, and poor organic sensing. Like surface warships, they are heavily dependent on outside cueing for launching fires, but their shallow magazine depth only allows them to fire relatively low volumes of fire, and they are generally harder to communicate with than surface warships.

The solitary nature of submarine operations severely constricts their ability to muster enough volume of fire. Compared to most other platforms, submarines are less likely to operate in groups and are more used to operating solo, which further limits the potential volume of fire. While they can certainly fit into a mass firing scheme or operational-level plan, if submarines do not operate as part of a distinct force package, then they will be less likely to generate standalone salvos or last-ditch fires of overwhelming volume.

An independently fired, close-range submarine salvo is a far cry from an aggregated salvo that is massed from contributing fires launched across distributed forces. If a submarine is to engage warships with missiles in independent circumstances, it will have to rely completely on its own missile magazine, which tends to be very shallow in attack submarines. A submarine’s entire vertical launch cell inventory could easily be depleted in a single attack if it is to have enough volume of fire to overwhelm multiple layers of warship defenses. If submarine-launched salvos are to have enough density and volume, then submarines must fire these salvos primarily from dedicated missile cells rather than through torpedo tubes. While torpedo tube-launched missiles can certainly supplement salvos, the fact that submarine torpedo tubes typically number in the single digits makes it highly dubious these tubes can discharge enough volume of fire on their own against high-end warships.

The current magazine capacity of the U.S. attack submarine force is relatively small at only 12 vertical launch cells and four torpedo tubes for Los Angeles– and Virginia-class submarines. Seawolf-class submarines have eight tubes and no launch cells.⁶ At 16 missiles, the maximum throw weight of these submarines per salvo is double that of a Harpoon-equipped U.S. destroyer or cruiser, or equal to four F/A-18 aircraft. But that will still be hardly enough to overwhelm alert warships with dozens of vertical launch cells and a range of point defenses. To launch effective missile attacks, submarines may be forced to close the distance to secure advantage at increased risk, or reduce their operational independence by heavily depending on outside fires to combine with their salvos.

While forthcoming variants of the Virginia-class submarine will have 40 vertical launch cells, these submarines will only start entering the fleet toward the end of this decade and will not feature in significant numbers until the decade after.⁷ The Navy’s four SSGN submarines have enormous capacity at 154 launch cells per boat, but they will be retired toward the end of this decade.⁸ After these four ships retire, the Navy’s submarine force will have relatively little anti-ship missile firepower for the next 15 years.

Submarines can still launch missile attacks against warships on somewhat favorable terms. By launching salvos from relatively close ranges, submarines can diminish the ability of the adversary to bring airpower to bear against the salvo, and can maximize the amount of time the salvo flies at sea-skimming altitudes. The result is a salvo that can spend most of its flight under a target warship’s radar horizon, and was fired from a range that is beyond the ability of shipboard anti-submarine weapons to be immediately brought to bear with confidence.

But the act of launching a salvo needs time and space to grow the volume of fire and then organize it into a specific pattern of attack, such as a saturation pattern. Submarine-launched salvos may require a minimum engagement range that is defined by these needs, where a submarine may need to use nonlinear waypointing to purchase enough time and space to grow and then organize the volume of fire before it attacks.

Submarines can earn additional advantages by firing from ranges closer than a target warship’s horizon. If a submarine missile attack is launched close enough, then vertically-launched missiles can struggle to reorient quickly enough to make the steeply angled intercepts. This can help negate much of a defending warship’s hardkill defensive firepower, allowing a smaller volume of fire to overwhelm defenses and destroying the warship quickly enough that it has virtually no time to discharge last-ditch fires, or even torpedos. However, the visual cues of such a short-range missile launch broaching the water could help a defending warship localize the attacking submarine more easily than a torpedo attack or over-the-horizon missile attack.

Despite their limited magazine depth, submarines play a valuable role in massed fires through their heightened ability to gain closer proximity to targets. This allows submarines to act as insurance against attrited fires and hastily organized firing sequences. If contributing fires are shot down, or if a salvo is fired on short notice, submarines may often be the only platforms that are close enough to a target to make additions to the volume of fire. A mass firing scheme that lacks enough submarines will have less ability to insure its firing sequences against attrition or short-notice launches. And as mentioned in Part 4, submarines can reap substantial benefit by sinking targets with torpedo attacks that are far less depleting than missile salvos, allowing them to substitute a handful of torpedoes for large volumes of missile firepower.

While submarine-launched salvos are especially taxing on their shallow missile magazines, a submarine depleted of missiles is not nearly as much of an at-risk asset compared to a warship or aircraft in the same situation. By operating beneath the sea, submarines are spared from the hefty air defense requirements of defending against anti-ship missile salvos. Even if its missile magazine is depleted, a submarine that has enough torpedoes in its inventory can still endure as a credibly threatening and survivable asset.

Launching long-range anti-ship salvos from submarines can present challenges with cueing their fires. If a submarine is to attack a warship at a distance that goes beyond the relatively short range of its organic sensors, external assets are likely required to cue its fires. Forms of low-frequency communication could provide this information. Certain platforms, especially aviation, could also be helpful in cueing submarine-launched missile fires within contested electromagnetic battlespaces. But the need for timely contributing fires and the ability of submarines to penetrate deep into contested seas could pose risks to platforms attempting to cue submarine-launched fires. Submarine-launched aerial drones can mitigate this to an extent by having an organic capability for enabling over-the-horizon fires.⁹ But submarine-launched drones may still not be capable enough for submarines to contribute especially long-range fires without external cueing.

The nature of cueing submarine launches can present challenges to leveraging contributing fires from submarines. Compared to the variety of platforms across the force, submarines are among the more difficult to communicate with by virtue of being undersea.¹⁰ If a commander wants a submarine to contribute fires to an aggregated salvo, it may involve more complex matters of communication and timing to leverage the capability.

Land-Based Forces and Stand-In Forces

Land-based missile forces can be divided into two broad categories – land-based launchers located on a nation’s homeland such as those of the PLA Rocket Force, and stand-in forces such as those envisioned by the U.S. Marine Corps. These distinct types of forces can play critical roles in massing fires.

Conventional land-based forces, such as those typically located on the homeland of a nation, can consist of coastal defense cruise missile launchers, missile silos, and transporter erector launchers. By virtue of being fielded by land-based platforms instead of more restrictive sea-based platforms, these weapons can take on extraordinary dimensions while still being fielded by highly distributed force structure. These attributes allow land-based missile forces to field some of the most powerful and survivable missile capabilities that exist today.

Land-based forces field some of the largest anti-ship missiles known, such as how a Chinese DF-26 is more than 15 times the weight of a Tomahawk.¹¹ The sheer size of these missiles allows them to maximize two key dimensions of capability – long range and high speed. By having more than a thousand miles of range, these weapons can hold numerous targets at risk on a theater-wide scale and with virtually no maneuver required on the part of the launch platform. Having high speed allows these weapons to travel those long ranges in remarkably short timeframes, which helps preserve the viability of the original targeting data. Through a combination of long range and high speed, these missiles feature a low time-to-strike across a broad area, which gives them a wide array of flexibility for combining fires with other types of missiles. A ballistic missile fired from a thousand miles away can still combine with a subsonic missile fired from a few hundred miles away, because both weapons only need tens of minutes at most to strike the same target.¹²

The anti-ship weapons that feature these especially high-end combinations of range and speed are mainly confined to hypersonic weapons and China’s anti-ship ballistic missiles. Weapons like the forthcoming land-based Tomahawk launchers will have similar ranges, but not nearly the same speeds. Yet having widespread land-based Tomahawk launchers will vastly multiply the potential distribution and volume of the U.S. military’s missile firepower.

Land-based forces can be extremely survivable and distributable. The scud hunt saga of Desert Storm showed how it was virtually impossible to find these types of launchers, even in open desert terrain with total air superiority.¹³ It would be even more challenging to attempt direct attacks on land-based launchers well within an adversary’s homeland, and copious amounts of effort could be expended in simply trying to pinpoint them for strikes. By being located on their homeland, these forces can benefit logistically from being near their sustainment infrastructure and enjoy remarkably fast reloads despite the size of their weapons.

Because of the steep challenges of inflicting attrition, countering land-based forces and their fires is mainly confined to countering the adversary’s broader ISR and C2 architecture. If the broader network is degraded, these forces will have little organic sensing to fall back on to generate standalone fires. Their especially heavy dependence on outside cueing makes these forces less operationally resilient and less likely to gracefully fracture into individual force concentrations in the context of a degraded network. By comparison, aircraft and warships can fall back upon their organic sensors to secure a measure of information for themselves when the broader network is degraded.

The lack of maneuverability relative to the speed and range of their weapons can also challenge land-based forces. If these forces are spread far and wide across an archipelago or the expanse of a homeland, they may not be able to maneuver to create denser fields of fire as easily as aircraft or warships can. Instead, their wide dispersal can yield fields of fire that remain relatively stretched thin in the early days of a conflict. Even if these weapons have extremely long range, dispersing these forces to fixed bases that are hundreds of miles apart can dilute the density of their combined fires.

Stand-in forces sharply differ from conventional land-based missile forces in key respects. Stand-in forces are expeditionary units deployed hundreds or even thousands of miles away from their homeland and onto relatively small islands proximate to the adversary. This results in much more challenging logistical requirements, which bottlenecks their capabilities. The logistical challenge of sustaining an expeditionary force makes it far more difficult for stand-in forces to field especially large, land-based missile launch platforms. Stand-in forces may be confined to fielding cruise missiles that are both less capable and less numerous than forces operating from their homeland.

Compared to most other types of forces, stand-in forces will be especially challenged to break through strong warship defenses using only what they have at their disposal. Instead, they may suffer similar disadvantages as submarines – able to achieve closer proximity to the adversary than most other platforms, but with smaller missile magazines on hand and therefore more dependence on outside contributors to achieve enough volume of fire. If stand-in forces deplete their shallow magazines, they may create substantial risks for resupply efforts. Using ships to reload stand-in forces in close proximity to adversaries may be far riskier compared to reloading warships or aircraft that are better able to withdraw beyond an adversary’s weapons engagement zone.

Stand-in forces positioned across island chains could provide timely intelligence that helps the distributed force mass fires against targets. Proximity to island chokepoints will simplify the task of both finding naval targets and massing fires against them. Compared to conventional land-based forces located deeper within a mainland, island-based stand-in forces will be better able to use their organic sensors to cue their own fires. It will be a challenge however for these stand-in forces to achieve broader situational awareness without organic aviation capabilities. High-altitude drones may prove far too vulnerable to last in such close proximity to an adversary, and significant amounts of manned aviation could be too difficult to sustain in advance bases.

While stand-in forces could make major contributions in cueing fires, they will be hard-pressed to mass meaningful volumes of anti-ship firepower on their own and to maintain aviation to secure valuable intelligence. And if stand-in forces struggle to field the larger-scale anti-air missiles that are needed to deny airspace at high altitudes, much of their ability to remain stealthy and manage signatures could be diminished by an adversary’s persistent aerial surveillance. The need for small footprints and low signatures is apparent, but it often costs signatures to detect signatures. These stealthy measures may be a critical enabler for a stand-in force, but they could also be a necessary evil when the stand-in force is heavily suppressed by the adversary.

Bombers

Bombers are one of the most advantaged platforms when it comes to contesting sea control, executing distributed operations, and attacking warships. Bombers feature a robust combination of traits, including high maneuver speed, fast reload times, significant on-station endurance, and an offensive magazine capacity that can approach that of surface warships.

While U.S. bombers have an unrefueled range that is similar to large surface warships, their high maneuver speed consumes this range at a much faster rate.¹⁴ While a bomber can travel thousands of miles on a single load of fuel, it will still need to be refueled within the same day, whereas warships can go days without refueling, allowing them to have greater near-term endurance. Yet bombers can rendezvous with aerial tankers in far less time than what it takes warships to meet with their tankers, allowing bombers to provide a substantial proportion of on-station, on-demand fires. The range and endurance of bombers allows them to loiter and be held on call for contributing to aggregated anti-ship fires on a theater-wide scale within hours. Their combination of decent magazine capacity and organic sensing capability can also allow bombers to launch last-ditch fires that approach the volume of warship-based fires but with greater accuracy.

An adversary may develop a sufficient sense of the aggregated firepower available to regional naval forces based on known warship capabilities and dispositions. But they may be less able to account for how airpower and especially bombers could be surged to contribute fires on short notice. Because of their combination of considerable speed and range, adversaries have to assume a wide array of bombers can provide a variety of distributed firing options to the opponent. U.S. warships homeported in the continental United States cannot factor as readily into the latent distribution and firepower posed by a forward U.S. fleet in the same way continentally-based bombers can.

For now U.S. bombers will be confined to firing anti-ship weapons like LRASM, whose early models feature less than half the range of the Maritime Strike Tomahawk.¹⁵ LRASM, like the Harpoon missile, has its capabilities confined by the requirement to be fired from multi-role aircraft that are much smaller than bombers. For the U.S., the ability of bombers to fire much larger missiles than multi-role aircraft will go largely unrealized for the anti-ship mission. Yet bombers test-fired air-launched variants of the Tomahawk decades ago in the Cold War and fielded other air-launched cruise missiles with ranges in excess of a thousand miles.¹⁶ The ability of bombers to contribute to anti-ship massed fires from standoff ranges will be magnified if they can fire cruise missiles that are similar to what can be fired from warship launch cells.

The U.S. Air Force is developing the potentially game-changing Rapid Dragon capability, which allows cruise missiles to be deployed from pallets dropped from airborne platforms.¹⁷ Similar in spirit to the Distributed Lethality concept’s mantra of, “if it floats, it fights,” this capability would introduce significant cruise missile capacity to hundreds of long-range Air Force transporter aircraft.¹⁸ Rapid Dragon would vastly expand the scope of force structure that can bring long-range missile firepower to bear and offer a major increase in force distribution. If the Air Force procures enough anti-ship missiles, this capability could be a major force multiplier for mass fires.

September 2021 – Over White Sands Missile Range, C-17 and EC-130 aircraft deploy the first Rapid Dragon pallets to release surrogate JASSM-ERs. (Lockheed Martin video)

Conclusion

Massed fires and naval warfighting are greatly enhanced when different platform communities form combined arms relationships. Combined force development and shared platform fluency will strengthen integration between communities. Warfighters will better understand their role in the combined arms team and the operational dynamics that govern the behavior of their cross-community partners. While these relationships will not be without friction or challenging tradeoffs, they will create a force that is far more effective than one that struggles to rise above its silos and parochialism. 

Part 7 will focus on aircraft carrier roles in distributed warfighting and massed fires.

Dmitry Filipoff is CIMSEC’s Director of Online Content and Community Manager of its naval professional society, the Flotilla. He is the author of the “How the Fleet Forgot to Fight” series and coauthor of “Learning to Win: Using Operational Innovation to Regain the Advantage at Sea against China.” Contact him at Content@Cimsec.org.

References

1. Jonathan M. House, Combined Arms Warfare in the Twentieth Century, University Press of Kansas, 2001.

2. See:

COMNAVAIRFORINST 3500.20D CH4, Chapter 3: Training Cycle. http://elearning.sabrewebhosting.com/CVnTraining/tramanfiles/chapter3.pdf

For balance of time between integrated and other forms of training see pg. 11 of: Bryan Clark and Jesse Sloman, “Deploying Beyond Their Means: America’s Navy and Marine Corps at a Tipping Point,” Center for Strategic and Budgetary Assessments, November 2015. https://csbaonline.org/uploads/documents/CSBA6174_(Deploying_Beyond_Their_Means)Final2-web.pdf

3. For vertical launch cell count for U.S. Navy, see:

“Report to Congress on the Annual Long-Range Plan for Construction of Naval Vessels for Fiscal Year 2023,” Office of the Chief of Naval Operations, pg. 9, https://media.defense.gov/2022/Apr/20/2002980535/-1/-1/0/PB23%20SHIPBUILDING%20PLAN%2018%20APR%202022%20FINAL.PDF. 

For VLS counts for Chinese and Japanese surface fleets, see:

Toshi Yoshihara, Dragon Against Sun: Chinese Views of Japanese Seapower, Center for Strategic and Budgetary Assessments, pg. 13, 2020, https://csbaonline.org/uploads/documents/CSBA8211_(Dragon_against_the_Sun_Report)_FINAL.pdf. 

4. An example of the low volume of fire that is inherent to these types of engagements can be seen in “Operation Desert Storm: Early Performance Assessment of Bradley and Abrams,” Government Accounting Office, pg. 23, January 1992, https://www.gao.gov/assets/nsiad-92-94.pdf. 

5. Wayne P. Hughes and Robert Girrier, Fleet Tactics And Naval Operations, Third Edition, pg. 188, U.S. Naval Institute Press, 2018.

6. For VLS and torpedo tube counts of U.S. Navy attack submarine types, see:

“Attack Submarines – SSN,” U.S. Navy Fact File, last updated March 13, 2023, https://www.navy.mil/Resources/Fact-Files/Display-FactFiles/Article/2169558/attack-submarines-ssn/.

7. For first VPM-capable submarine keel-laying ceremony, see the below. Based on traditional submarine construction and commissioning timelines, this ship will not enter the fleet until near the end of this decade. 

Team Submarine Public Affairs, “Navy Authenticates Keel for Future USS Arizona (SSN-803),” December 7, 2022, https://www.navy.mil/Press-Office/News-Stories/Article/3238746/navy-authenticates-keel-for-future-uss-arizona-ssn-803/. 

8. Ron O’Rourke, “Navy Virginia (SSN-774) Class Attack Submarine Procurement: Background and Issues for Congress,” Congressional Research Service, pg. 10, December 21, 2022, https://crsreports.congress.gov/product/pdf/RL/RL32418/231.

9. Thomas Newdick, “The U.S. Navy’s Submarine-Launched Aerial Drone Capacity Is Set To Greatly Expand,” The Warzone, March 10, 2021, https://www.thedrive.com/the-war-zone/39700/the-u-s-navys-submarine-launched-aerial-drone-capacity-is-set-to-greatly-expand.

10. Bryan Clark, “The Emerging Era in Undersea Warfare,” Center for Strategic and Budgetary Assessments, pg. 13, 2015, https://csbaonline.org/research/publications/undersea-warfare.
11. For launch weights of Tomahawk and DF-26 missiles, see:

“Tomahawk,” CSIS Missile Defense Project, last updated February 28, 2023, https://missilethreat.csis.org/missile/tomahawk/.

“DF-26,” CSIS Missile Defense Project, last updated August 6, 2021, https://missilethreat.csis.org/missile/dong-feng-26-df-26/.

12. This estimate is based on the typical flight times of similar intermediate range ballistic missiles. See:

Bruce G. Blair, Harold A. Feiveson and Frank N. von Hippel, “Taking Nuclear Weapons off Hair-Trigger Alert,” Scientific American, November 1997, https://sgs.princeton.edu/sites/default/files/2019-10/blair-feiveson-vonhippel-1997.pdf. 

Dr. Jamie Shea, “1979: The Soviet Union deploys its SS20 missiles and NATO responds,” NATO, March 4, 2009, https://www.nato.int/cps/en/natohq/opinions_139274.htm. 

Charles Maynes, “Demise of US-Russian Nuclear Treaty Triggers Warnings,” Voice of America, July 31, 2019, https://www.voanews.com/a/usa_demise-us-russian-nuclear-treaty-triggers-warnings/6172981.html. 

13. Colonel Mark E. Kipphutt, “Crossbow and Gulf War Counter-Scud Efforts: Lessons from History,” The Counterproliferation Papers Future Warfare Series No. 15 USAF Counterproliferation Center Air University, pg. 18-20, February 2003, https://media.defense.gov/2019/Apr/11/2002115481/-1/-1/0/15CROSSBOW.PDF.

14. For range of U.S. Navy surface warships, see:

“Transforming the Navy’s Surface Combatant Force,” Congressional Budget Office, pg. 5, March 2003, https://www.cbo.gov/sites/default/files/report_0.pdf.

For range of U.S. Air Force bombers, see:

“B-52H Stratofortress,” U.S. Air Force Fact File, https://www.af.mil/About-Us/Fact-Sheets/Display/Article/104465/b-52h-stratofortress/.

“B-2 Spirit,” U.S. Air Force Fact File, https://www.af.mil/About-Us/Fact-Sheets/Display/Article/104482/b-2-spirit/.

Lt. Gen. David A. Deptula USAF (Ret.), “Maritime Strike,” Air and Space Forces Magazine, September 1, 2019, https://www.airandspaceforces.com/article/maritime-strike/.

15. For Tomahawk range, see:

“Tomahawk Cruise Missile,” U.S. Navy Fact File, last updated September 27, 2021, https://www.navy.mil/Resources/Fact-Files/Display-FactFiles/Article/2169229/tomahawk-cruise-missile/.

The LRASM range of 350 miles is a rough estimate deduced from the JASSM missile it is derived from, see:

“Options for Fielding Ground-Launched Long-Range Missiles,” Congressional Budget Office, pg. 2, 2020, https://www.cbo.gov/publication/56143.

16. For Cold War-era Air Force air-launched cruise missiles featuring ranges in excess of a thousand miles, and that did enter service, see:

“Boeing AGM-86B ALCM,” Minot Air Force Base fact file, last updated January 2014, https://www.minot.af.mil/About-Us/Fact-Sheets/Display/Article/805942/boeing-agm-86b-alcm/. 

17. For Rapid Dragon capability, see:

“Rapid Dragon,” Air Force Research Lab, https://afresearchlab.com/technology/rapid-dragon. 

Tech. Sgt. Brigette Waltermire, “AFSOC conducts live-fire exercise with Rapid Dragon,” Air Force Special Operations Command Public Affairs, November 14, 2022, https://www.af.mil/News/Article-Display/Article/3216532/afsoc-conducts-live-fire-exercise-with-rapid-dragon/.

18. For Air Force inventory of transporter aircraft, see:

“2022 USAF & USSF Almanac: Equipment,” Air and Space Forces Magazine, July 1, 2022, https://www.airandspaceforces.com/article/2022-usaf-ussf-almanac-equipment/. 

Featured Image: Atlantic Ocean (July 12, 2004) – The Los Angeles-class submarine USS Albuquerque (SSN 706) surfaces in the Atlantic Ocean while participating in exercise Majestic Eagle 2004. (U.S. Navy photo by Photographer’s Mate Airman Rob Gaston)

Read Part 1 on defining distributed maritime operations.
Read Part 2 on anti-ship firepower and U.S. shortfalls.
Read Part 3 on assembling massed fires and modern fleet tactics.
Read Part 4 on weapons depletion and last-ditch salvo dynamics.

By Dmitry Filipoff

Introduction

There is more to the lethality of a volume of fire than sheer numbers. Missile salvos can take on different patterns, both in how the missiles are arranged within a single salvo, and how multiple salvos can be arranged together into a combined volume of fire. These patterns reflect how the aspects of concentration and distribution apply to the weapons themselves, and how these configurations apply within salvos and between salvos. Different patterns will affect how a volume of fire takes shape and can multiply the threat it poses. Commanders and autonomous missiles can leverage these patterns to increase tactical advantage by changing how salvos are maneuvered throughout key elements of the fight. These patterns have considerable tactical implications for defending against missiles and maximizing offensive volume of fire.

Stream versus Saturation

It is infeasible for a warship to instantly fire a large volume of missiles all at once. While warships can certainly fire missiles rapidly, their rate of fire is typically limited to only a few missiles at a time from the whole of their launch cells.¹ Because the entirety of a salvo cannot be fired at once, salvos often default to a stream pattern, where a long, vertical column of missiles travels toward a target (Figure 1). Each missile in the column is slightly further away from the target than the missile ahead of it, because each missile was fired slightly later than the missile before it.

Figure 1. Click to expand. A warship launches a salvo in a stream pattern. (Author graphic via Nebulous Fleet Command)

This typical salvo pattern has several disadvantages, such as how an attacking stream salvo can allow the defender to more easily defeat the missiles in detail. If the streaming missiles are flying closely enough along the same flight path, destroying missiles at the head of the stream can disrupt missiles further behind as they may have to fly through exploding shrapnel and debris. A stream salvo can also minimize the maneuvering and targeting readjustments needed to apply warship defenses that are more directionally limited, including mounted defenses such as laser dazzlers, rolling airframe missile launchers, and close-in weapon systems (Figure 2). 

Figure 2. Click to expand. A close-in weapon system engages multiple missiles of a stream salvo approaching on a single axis. (Author graphic via Nebulous Fleet Command)

Alternatively, a saturation pattern has greater tactical advantages. Instead of flying in a staggered sequence or vertical column, the missiles are traveling abreast of one another in a wide horizontal row. This salvo pattern poses a broad front of concentrated firepower compared to the long and narrow front of a stream salvo, where a saturation salvo takes the form of a multi-axial attack instead of the stream’s single axis. Once a saturation salvo crosses over the horizon, all of the missiles aim to be at a similar distance from the target warship, intensifying the challenges of defense. Directional defenses will need to traverse more angles to acquire new targets, and the attacking missiles run a lesser risk of having to fly through the exploding debris fields of their destroyed colleagues (Figure 3).

Figure 3. Click to expand. A close-in weapon system engages a saturation salvo’s missiles across multiple axes. (Author graphic via Nebulous Fleet Command)

Platforms that feature small magazines and larger numbers, such as aircraft, truck launchers, and small missile ships can more readily assemble into firing formations that generate saturation patterns from the onset. But the feasibility factors that bottleneck a warship’s rate of fire make a saturation pattern more unnatural for a warship to launch than a stream pattern, where warships can only launch large salvos in streams. The missiles will have to be maneuvered into a saturation pattern after the salvo is fired. Ideally this will be facilitated by networking and autonomy on the part of the missiles, rather than a complex firing scheme on the part of the launch platform. Modern anti-ship missiles will be able to be programmed to self-organize into a saturation pattern after they are launched from a warship, or outside retargeting and in-flight updates could provide similar instructions.² By maneuvering weapons after they are launched, these capabilities serve the critical function of helping a salvo’s missiles maximize the overlap of impact timing regardless of the launch platform’s rate of fire.

In salvo combat, if a missile is not able to hit the target because it was shot down by defenses, the next best thing is that its destruction can buy a sliver of time for another missile in the salvo to have a slightly better chance of striking. This dynamic can continue throughout an engagement, where through their destruction, missiles are buying small consecutive improvements in striking opportunity for other missiles. The way impact timing is distributed across a salvo’s missiles will affect how much opportunity the destroyed weapons purchase for the survivors. A majority of a salvo’s missiles will likely be destroyed in the process of ensuring that only a handful have a real chance of striking the killing blows.

Stream patterns stretch the volume of fire thin with respect to the timing of impact. Each missile in the salvo would impact the target at a slightly later time than the missile ahead of it, where the distribution of impact times across a stream salvo is mainly limited to being a function of the launching warship’s rate of fire. If defenses are robust enough, a defender can even keep a stream salvo at a fixed distance away from the target until the salvo is fully destroyed. The ability for stream salvo missiles to buy time for one another is diminished by how destroying the missile at the head of the pack slightly rolls back the clock.

What a saturation pattern offers is a salvo that is always closing the distance regardless of the extent of attrition. Even if missiles are being destroyed, the minimum time to impact is steadily winding down. The volume of simultaneous defensive effects required to keep the whole of a saturation salvo at a fixed distance away from a target warship is far higher than that of a stream salvo, because it would require destroying the entirety of the saturation salvo simultaneously.

A saturation salvo epitomizes the principle of concentrating effects, where all missiles in the salvo are angling to strike the target at the same time, and bring the full weight of the entire volume of fire to bear at once. Saturation salvos improve efficiency by maximizing concentration, and can reduce the number of offensive weapons required to overwhelm warship defenses.

Because defensive missiles typically have much less range and flight times than long-range anti-ship missiles, they have far less opportunity to be maneuvered into saturation patterns, especially when they must strike incoming missiles that are only miles or seconds away from impact. Saturation patterns can chiefly be a feature of attacking salvos, while a warship’s defending salvos are more likely to be relegated to stream patterns. This forms a critical asymmetry in the offensive-defensive balance and confers significant advantage to the attacker in naval salvo warfare.

Salvo Patterns and Tactical Information

One of the most critical considerations for preserving missile inventory and preventing wasteful fires is guarding against deception and maintaining quality targeting information while salvos are traveling toward distant targets. Salvo patterns heavily influence the tactics of missile search and deception, especially given how capable modern seekers have become.

Anti-ship missiles are difficult to evade and deceive when their onboard seekers feature a robust combination of sensor modes including infrared, electro-optical, active, passive, and others. These combined sensors are meant to work together to maximize their strengths while covering each other’s blindspots. They aim to simplify the challenge of terminal search while negating softkill capability. A passive radar receiver can often detect a target or radiating decoy at longer range than an electro-optical sensor, but the latter is much harder to deceive when the contact enters within visual range.³ At that range missiles will be especially challenging to deceive, where they are close enough to visually verify a target’s authenticity. And once they make their final approach, the missiles’ targeting logic can employ aimpoint selection capability, where they select the most lucrative impact points on a ship to maximize destructive potential, such as hitting a ship directly in its missile magazines.⁴ Aimpoint selection capability makes effective damage control a dubious proposition and helps ensure that only a single well-placed hit is enough to destroy a target, reducing the volume of fire necessary to inflict sufficient striking power.

These electro-optical and infrared sensors are major force multipliers by making it much easier for missiles to ignore the short-ranged warship-launched decoys that form a major portion of a warship’s softkill defenses. Even if these decoys pull a missile away from a ship at the last moment, an intelligent missile would know to circle back for another pass, where the decoy only buys the warship more time to shoot down the threat. Effective softkill deception against intelligent missiles therefore needs to occur at a distance that goes well beyond the horizon. Otherwise deception measures that occur within the horizon view of a warship will struggle to have an effect against missiles that can literally see the warship.

Successfully deceiving these anti-ship missiles may be less likely to take the form of getting them to strike false targets. It may instead become more a matter of keeping them at arm’s length and pulling them in directions away from friendly forces until they waste enough time and fuel that they fall from the sky. But most of a typical warship’s decoy capability is very short-ranged, and warships are extremely limited in their ability to deploy decoys tens of miles away from the ship. They may have to rely on other platforms such as aviation to deploy decoys at a tactically meaningful distance away from the warship.

Once a salvo is fired against a warship, an area of uncertainty grows around the target, where the warship may have moved from its original position at the time of launch, and where decoys may be deployed within this area of uncertainty. This area of uncertainty remains relatively small for the speediest weapons and missiles with short times-to-target. But for long-range and subsonic weapons, this area can grow to include thousands of square miles.⁵ If the area of a missile seeker’s coverage can overlap most of the area of uncertainty, then the problem of terminal homing is somewhat simplified. But if the area of uncertainty exceeds seeker coverage, then missiles may need to rely more on their own search capabilities to find and discriminate contacts for attack in the final phases.

Saturation patterns maximize the ability of a salvo to search and find a target. A saturation pattern spreads missile seekers across a wide front, allowing each seeker to search a given axis (Figure 5). If a seeker acquires a target, in-flight networking and autonomy between missiles can allow them to converge on a specific contact. A stream salvo by comparison makes for a highly redundant search pattern by concentrating seekers along a single axis, which is hardly ideal for searching across an area of uncertainty (Figure 4).

Figure 4. Click to expand. The seekers of a stream salvo pattern search along a narrow axis. (Author graphic via Nebulous Fleet Command)

Figure 5. Click to expand. The seekers of a saturation salvo search across multiple axes. (Author graphic via Nebulous Fleet Command)

Missiles can be drawn to contacts that turn out to be decoys, which may need to be discriminated by much shorter-ranged seeker modes than radar, such as electro-optical or infrared sensors. The need for missiles to close the distance to more rigorously investigate and verify contacts can threaten the cohesion and range of the salvo. Relying on only a few missiles at the head of a stream to do most of the searching on behalf of the salvo runs a greater risk of having the whole salvo being led astray by false contacts, which will come at a significant cost to fuel, range, and time. Advanced networking and autonomy may do little to alleviate the inherent tunnel vision of a stream salvo, where the whole of the salvo can be made to suffer penalties if only the leading missiles are deceived. If the missiles lack the programming and networking to work together, a stream salvo encountering a decoy could fragment and lose its cohesion as some missiles take the bait and others do not.

In a primitive stream salvo, the pattern of searching for a target and attacking a target remains virtually the same, compared to the more dynamic expansion and contraction of a saturation salvo that widens while searching for a target and then converging on it. A saturation salvo is much better able to withstand the disruption decoys can inflict against the coherence of the volume of fire. When the salvo is searching across a wide front, a single weapon could investigate a contact and make sure to only cue the rest of the salvo to converge on the contact after it has been verified. This helps a saturation salvo reduce the cost of deception to a single weapon or a handful of weapons being led astray at a time, rather than larger segments of the salvo like a stream pattern. However, if the deception is effective enough to get networked missiles to cue convergence, then a saturation salvo that is made to repeatedly expand and contract as it converges on false contacts and then renews its search is a salvo that will be quickly running down its mileage.

Stream salvos may offer some informational advantages when it comes to battle damage assessment and assessing the effectiveness of an attack. Missiles later in the stream could use their sensors to perceive that the target ahead has been destroyed and communicate fresh battle damage assessment information to the network. Or they could communicate that the vast majority of the missiles ahead them have been destroyed by defenses and strongly suggest that a salvo is on the verge of being defeated. In either case, missiles could deliver especially critical and time-sensitive intelligence on the effectiveness of attacks and defenses, assuming they are able to deliver such information through a network in those contexts. A saturation salvo that simply maintains several weapons to the rear of the main wave of attacking missiles could deliver similar information.

If the targeting and search capabilities of salvos are capable enough, they can lower the threshold of information required to precipitate a strike and speed the decision cycle. If the missiles are capable enough to sort out contacts and even decide their own distribution of fire across a target naval formation, then commanders can launch on less information knowing the missiles themselves can reliably sort out critical details. If an adversary is presenting a mass of cluttered signatures that makes target discrimination difficult from afar, saturation salvos could be fired into the mass in a bid to earn positive identification themselves and function as one-way scouts. Modern seekers that can visually identify a target based on robust onboard databases of warship designs should be capable enough to differentiate most warships from civilian vessels and minimize the ability of navies to use commercial traffic as human shields.

With respect to the vulnerability of the launch platform, a stream salvo can more easily betray the position of its launching warship by providing a clearly defined line of bearing back toward the vicinity of the platform. A warship under attack from a stream salvo could fire its offensive weaponry down this line of bearing in a last-ditch salvo and have a greater chance of striking back. Nonlinear flight paths and saturation patterns can help mitigate this risk through multi-axis attacks that can manipulate perceptions of where an attack originated.

But nonlinear attacks and saturation patterns incur penalties in range and fuel economy. Stream salvos will suffer less penalties than saturation salvos in this regard because it is more fuel efficient to maneuver a salvo across waypoints when maintaining a stream pattern. By comparison, saturation salvos will suffer a greater cost in fuel given how some missiles will have to cover more distance than others to preserve the abreast formation while traveling across waypoints. It may be more preferable to confine a saturation pattern to the terminal phase of attack rather than the cruise phase of missile flight, where a stream salvo only expands into a saturation profile just before breaking over the target’s horizon.

Salvo patterns can therefore be flexed during flight to emphasize search, fuel economy, or lethality depending on what is more applicable at various points in the engagement. The need for maximizing range and fuel may compete with the need to search and withstand deception, where these latter factors encourage a saturation pattern. If enough outside retargeting support can confidently convey information to a salvo during flight, then it can minimize the amount of fuel the salvo would have to expend in a broader search pattern. This can also improve the survivability of the salvo and improve its element of surprise, where a saturation pattern engaged in search could provide more early warning to an adversary by posing a radiating wall of missile seekers. Even emphasizing passive detection can reduce the element of surprise, since missiles may have to leave sea-skimming altitudes to broaden the reach of their sensors. Outside retargeting support is helpful toward improving the range and survivability for missile salvos on their way to the target by allowing them to maintain low-altitude stream patterns, and reduces the need for saturation patterns to only the final moments of attack.

A salvo of Soviet P-500 Bazalt anti-ship missiles (NATO reporting name: SS-N-12 Sandbox) is fired by a Slava-class cruiser against a U.S. Cold War-era surface action group. Demonstrated intelligent missile swarming behaviors include self-organization from stream pattern into saturation pattern, single high-altitude missile searching on behalf of larger sea-skimming salvo, target prioritization for distribution of fire, and weaving flight profiles in terminal attack phase. Blue trails mark offensive missiles, pink trails mark defensive missiles. (Work-in-progress developer video of forthcoming naval wargame, Sea Power: Naval Combat in the Missile Age.)

Patterns of Combining Fires

Saturation and stream patterns go beyond describing individual salvos, where they can also describe the broader aggregated salvo as a whole. Depending on how contributing fires are being amassed from distributed forces, the aggregated salvo itself may take on an overall stream or saturation profile, or some mixture of the two. The overall profile of an aggregated salvo may feature an amalgamation of waypointing and salvo patterns that generate especially complex threat presentation as a shapeshifting volume of fire closes in on a target (Figure 6).

It is easier to combine with stream salvos than saturation salvos. Because not all missiles in a stream salvo will hit the target at the same time, there is slightly more opportunity to overlap with the salvo, which can measure in the tens of seconds. A saturation salvo will pose greater challenges for effective aggregation because the salvo is already attempting to position all its missiles to strike the target at the same time. Outside salvos attempting to combine with saturation salvos will have to be very closely aligned in timing because of the minimum of opportunity for overlap.

In-flight retargeting and programming can play a critical role in ensuring aggregation can maximize opportunity for saturation. Multiple contributing salvos can approach a target as streams and then travel waypoints in a holding pattern beyond the target’s horizon until more contributing fires arrive. Once the final attack is initiated, the contributing fires switch to saturation patterns and converge on the target. The efficiency of the stream pattern buys more time to grow the volume of fire, and the lethality of the saturation pattern is reserved for the final approach.

As various contributing fires approach a target, the defenders may prioritize the destruction of specific salvos based on their patterns. Defenders may prioritize saturation patterns especially, believing them to be the greater threat. The more complex the flight profile and missile behavior, the more an adversary may assume that a set of contributing fires consists of more capable missiles, and prioritize those salvos for interception by its defensive airpower and other means.

Salvo patterns can be flexed to manipulate adversary threat perceptions and potentially open gaps in defenses. By flexing a combination of salvo patterns and waypoints, a set of contributing fires could expand into a saturation profile to draw adversary airpower away from a target and open opportunities for other salvos to make the strike. And as a salvo comes under attack from airpower, it can shift its flight profile as it senses radar illumination and notices that friendly missiles are disappearing from the local network. By shifting flight profiles while under aerial attack, a missile salvo can make defense more challenging and buy time for the overall strike. Primitive anti-ship missiles by comparison may hardly change their flight behavior when under attack or radar illumination, simplifying the defender’s challenge.

Salvo Patterns: A Forthcoming U.S. Advantage?

The ability to leverage the tactical advantages of salvo patterns may be one of the key advantages the U.S. will have over China by fielding the anti-ship capable variants of the Tomahawk missile, assuming China does not develop similar weapons. The Tomahawk missile’s especially long range gives it great flexibility for maneuvering through various patterns and along many waypoints. Greater range also improves the missile’s ability to recover from deception by false contacts and extend its search for real targets. These capabilities are magnified by another dimension of salvo patterns, that of sea-skimming versus high-diving attacks.

Anti-ship ballistic missiles can take on saturation patterns by virtue of being launched by multiple platforms with shallow magazines, such as truck launchers. But despite having similar range as Tomahawk, anti-ship ballistic missiles are heavily disadvantaged when it comes to reconfiguring their salvo patterns in real time. The fixed nature of a ballistic trajectory strongly constrains the ability of these weapons to alter the disposition of their salvos while in flight, and the steep high-diving nature of their final approach constrains the scope of ocean their onboard seekers can search across.⁶ A ballistic missile on its terminal descent cannot decline a false contact and then default back to a wider search pattern as easily as a cruise missile. A ballistic missile locked into its terminal descent is only moments away from hitting the ocean regardless of whether its targeting information is viable or not, whereas a cruise missile has more margin for error. By their nature, ballistic missile attacks attempt to minimize the area of uncertainty around a target not so much by coordinating search across a salvo’s seekers, but more by having tremendously high speed that helps preserve the viability of the original targeting information given at launch.

The differences in terminal search and attack patterns between ballistic missiles and cruise missiles is somewhat similar to that of the attack profiles of WWII dive bombers and torpedo bombers, respectively. The dive bomber, like a ballistic missile, makes its final approach from a steep angle at higher altitude, exposing itself to a broader array of sensors and defensive firepower, while having relatively little leeway to shift to new targets midway through its high-speed dive. The torpedo bomber by comparison is usually traveling more slowly, but its flight profile is at a flatter angle that affords it much more maneuverability, even in the terminal attack phase. This flatter flight profile offers a broader scope of opportunity to investigate contacts, recover from deception, and shift targets, while giving the platform more options in when it begins its terminal approach.

A sea-skimming cruise missile is therefore better able to employ a wider search pattern across the area of uncertainty around a target than a weapon locked into a high-diving flight profile. While the visibility of sea-skimmers is more deeply affected by horizon limits than high-divers, a high-diving platform or missile may struggle to radically reorient itself toward a new contact during its dive, and the smaller size of the seekers used by missiles can limit how much those weapons can leverage the broader visibility for search. However, sea-skimming attackers may have to break through successive layers of defending warships and aircraft before they can threaten a priority target in the interior of a formation. In exchange for some disadvantages, high-diving attackers can threaten those priority targets directly.

Conclusion

Sharpening the intelligent swarming behaviors of anti-ship missiles will be a key area of naval competition, one with significant potential for building offensive advantage. These capabilities should be expected to proliferate and magnify missile threats. Navies should take care to assess the programming and autonomous targeting logic of their salvos to consider how this may make their striking power concentrated or stretched thin during an attack. When warship salvos have little in the way of effective networking or autonomy, they default to more primitive stream salvo patterns and suffer major disadvantages. They become more susceptible to deception, struggle with long-range search, and raise the cost of attack.

As a distributed force masses its fires, it will attempt to maximize the saturation effect. In those final phases of attack, the greatest offensive advantage will be gained when saturation patterns characterize how salvos are arranged as they converge on a target. What these salvo patterns make clear is that in the missile age, the weapons themselves have become a chief maneuver element.

Part 6 will focus on the strengths and weaknesses of platform types in distributed warfighting.

Dmitry Filipoff is CIMSEC’s Director of Online Content and Community Manager of its naval professional society, the Flotilla. He is the author of the “How the Fleet Forgot to Fight” series and coauthor of “Learning to Win: Using Operational Innovation to Regain the Advantage at Sea against China.” Contact him at Content@Cimsec.org.

References

1. Factors that bottleneck a warship’s rate of fire from vertical launch systems include exhaust gas limits and safety risks of launching numerous missiles in very close proximity to one another. The minimal unit of a MK41 vertical launch system takes the form of eight-cell module, with each module sharing a common exhaust gas system. 

For module and exhaust gas design of MK 41 VLS, see:

Eric Fiore, “A Promising Future for US Navy Vertical Launch Systems,” DISIAC Journal, Volume 1, Number 2,, pg. 35, Fall 2014, https://www.dsiac.org/wp-content/uploads/2020/05/dsiac-journal-fall-web-1.pdf.

2. John Keller, “Lockheed Martin to build six more LRASM anti-ship missiles with GPS/INS, infrared, and radar-homing sensors,” Military and Aerospace, March 23, 2022, https://www.militaryaerospace.com/sensors/article/14248345/multimode-sensors-antiship-missiles.

3. Wayne P. Hughes and Robert Girrier, Fleet Tactics And Naval Operations, Third Edition, pg. 188, U.S. Naval Institute Press, 2018.

4. For aimpoint selection capability, see: 

“JSM: Joint Strike Missile,” Kongsberg, https://www.aerocontact.com/public/img/aviaexpo/produits/catalogues/92/Brochure-Joint-Strike-Missile.pdf. 

5. Jeffrey R. Cares and Anthony Cowden, “Fighting the Fleet: Operational Art and Modern Fleet Combat,” U.S. Naval Institute Press, pg. 30-42, 2021.

6. Gerry Doyle and Blake Herzinger, Carrier Killer: China’s Anti-Ship Ballistic Missiles and Theater of Operations in the early 21st Century, Helion & Company, pg. 42, 2022.

Featured Image: US joint forces conducted a sinking exercise on the decommissioned guided missile frigate ex-USS Ingraham in the Hawaiian Islands Operating Area, 15 August 2021. (US Navy photo MCS David Mora Jr)

Read Part 1 on defining distributed maritime operations.
Read Part 2 on anti-ship firepower and U.S. shortfalls.
Read Part 3 on assembling massed fires and modern fleet tactics.

By Dmitry Filipoff

Introduction

Modern naval combat can consist of forces firing dozens if not hundreds of missiles at one another’s fleets and salvos. These volumes of fire can be unleashed within mere minutes as forces look to launch offensive and defensive salvos that are large and dense enough to kill and defend warships. Yet these sophisticated weapons are available in limited numbers and require long lead times to produce.¹ Only a fraction of these inventories are available for immediate use given how the magazines of the operating force’s platforms are distinct from the weapon stocks they draw from. Militaries can be limited to using the weapon stocks they had shortly before conflict broke out, and a short conflict may be decided by what was mainly fielded in platform magazines. Unless the conflict becomes especially prolonged and the industrial base grows significantly, the inventory of precision weapons will steadily diminish and pose critical constraints. A core operational challenge is how to carefully manage weapons depletion while still unleashing massed fires.

Weapons depletion is in its own right a powerful force for shaping warfighting behavior and securing major operational advantage. The larger consequences of depletion can include steep decreases in unit availability and overall operations tempo on a theater-wide scale. This challenge is especially severe for the U.S. Navy given how long it would take a depleted U.S. warship to travel out of a Pacific battlespace, rearm in safe havens, and return to the fight.² In a short, sharp conflict featuring intense salvo exchanges, a warship that depletes itself only once may very well miss the rest of the war.

The concentration and distribution of a force will flex and evolve as its platforms suffer depletion. As commanders look to employ mass fires, they must be mindful of how to spread depletion across the force, how to interpret the adversary’s expenditures, and how inventory pressures can be manipulated through the last-ditch salvo dynamic.

Distribution and Depletion

One of the critical advantages of massing fires from distributed forces is the ability to more effectively manage depletion. A distributed force fielding a vast array of overlapping firepower makes for an especially large and shared magazine. This offers a much greater chance of mustering enough firepower to overwhelm robust defenses while achieving a better spread of depletion. Depletion can be spread across a broader scope of platforms and occur more gradually across the force, rather than all at once for individual strike platforms and force packages. Spreading depletion prolongs distribution, because every depleted asset makes the remaining force less distributed and more concentrated.

Some platforms and force packages certainly have sufficiently deep magazines to launch large enough volumes of fire on their own, with less of a need for outside contributing salvos. But large standalone salvos diminish a core tenet of distribution – maintaining many spread out threats to complicate adversary targeting. Forces that fire large standalone salvos can quickly give away that they just depleted most of their offensive firepower, reducing their value as targets and diminishing the distribution of the broader force.

The more a platform has to discharge a large number of missiles to contribute fires, the more easily an adversary can ascertain the composition and depth of their remaining inventory. A U.S. destroyer that fires 30-40 Maritime Strike Tomahawks in a single large salvo can give away that it has little remaining long-range anti-ship weaponry. By comparison, massing fires from a broader array of distributed forces makes it harder for an adversary to ascertain when platforms and formations have depleted their individual magazines.

Aggregation allows firepower to be combined in smaller portions from individual launch platforms. Ideally each launch platform can afford to expend only a small fraction of its magazine at a time, if many other platforms are doing the same with proper timing and coordination. Individual platforms will be able to sustain distributed offensive threats for longer than if they had fired off large, independent salvos of their own.

However, as inventory begins to dwindle across a distributed force, mass fires can cause larger portions of the force to reach the end of their magazines around a similar timeframe. This could radically collapse the offensive posture and capability of the distributed fleet if not carefully managed. By delaying magazine depletion at the individual platform level, mass fires risk magazine depletion across a broader portion of the force at a later time.

Consider a fleet that has four distributed warships available for contributing fires. If one warship emptied its entire offensive inventory per strike, then the remaining force becomes increasingly concentrated and predictable as to where the next several strikes may come from. Instead, if those four warships combine fires to launch a quarter of their offensive inventory per strike, the distributed force posture endures for more time and across more attacks. But all of those warships would deplete at a similar time, triggering a larger drop in force distribution compared to depleting only one platform per strike through the first scheme. By spreading depletion to prolong distribution, mass fires trade smaller decreases in distribution earlier in the fight in exchange for larger decreases later on.

Having deeper magazines or more strike platforms reduces the share of magazine depth each attacker must deplete to contribute to mass fires, and further delays the broader depletion of the force. A distributed force posture can be preserved by having a large number of assets with overlapping firepower, or rotating assets quickly enough to replace those that have depleted their magazines. The goal is to maintain enough available firepower over time so the distribution of the force can endure.

Asymmetric Weapons Depletion and Operational Risk

There are important asymmetries in how warships can deplete their offensive missile firepower versus their defensive firepower. One asymmetry is that commanders may be deeply uncomfortable keeping large surface warships in the battlespace when they are low on defensive firepower but fuller on offensive firepower compared to the reverse situation. Another key asymmetry is that defensive firepower is mostly drawn from the local magazines of the naval forces under attack, while offensive firepower can be drawn from the many magazines of a broader distributed force. Leveraging these key asymmetries can secure operational advantage.

Even if a ship survives an intense attack, being on the wrong side of firing effectively first can take the form of being low on defensive firepower while still full on unused offensive firepower. These units can still remain offensive threats, but the volume of fire required to overwhelm their defenses is substantially lowered. This can force commanders to pull these units out of the fight for the sake of survival and replenishing their defenses.

In this sense, firing effectively first is not only defined by scoring successful hits and kills, it can also mean depleting enough of the adversary’s defenses that commanders no longer feel confident in pressing their attack or maintaining warships in a contested battlespace. If those depleted warships are in escort roles and are responsible for defending other ships, then those ships could be forced to withdraw as well. By depleting defensive firepower to the point that warships must be withdrawn before they can attack, those warships’ offensive inventory can be removed from the fight before it can be used, thereby suffering depletion indirectly.

The battle of nerves in naval salvo warfare is partly a function of accepting risk for the sake of minimizing weapons depletion. A more efficient missile exchange tolerates more risk, demanding stronger nerves on the part of commanders. Otherwise, the desire to build more confidence into offensive or defensive engagements can make commanders waste their munitions. A defending warship that fires too many anti-air weapons per incoming missile wants to bolster its odds of near-term survival, but it can deplete itself earlier than warranted and increase risk in follow-on engagements. A warship that fires an excessive amount of anti-ship weapons can risk too much overkill and leave it with little offensive capability for later in the fight.

But commanders who attempt to precisely optimize their offensive salvos in a bid to just barely overwhelm targets with enough fire will risk much greater uncertainty than those willing to accept overkill by expending more volume. Indeed in a form of combat featuring salvos with dozens of missiles that only need to strike a single hit, overkill is more likely than not. Instead, it is the degree of overkill that separates what is sufficient from what is wasteful. Achieving a small degree of offensive overkill can be the more efficient outcome, since attacking with an insufficient volume of fire can lead to waste by making follow-on salvos once again pay the price of breaking through strong defenses to threaten a target. With too much overkill, a unit or commander witnessing a heavy volume of fire pouring into a dead or dying friendly warship may take some small satisfaction in knowing the enemy just suffered depletion far out of proportion to their target.

A key asymmetry is how the risk of depletion through overkill is much more manageable for offensive fires because of the greater ability to mass those weapons from across many forces. Defensive inventory has far less margin to work with because of the isolating effect of the radar horizon on ship self-defense, where there is little ability for ships to leverage a broader shared magazine against sea-skimming threats. An attack on a naval formation can consist of fires pulled from a wide variety of forces, but the formation will often have only its own magazine to defend itself. And with that magazine, the formation may not only have to match the incoming volume of fire, but exceed it to ensure survival. Matching the attacking volume with only one interceptor fired per incoming missile may not be enough to confidently survive a dynamic where a warship cannot afford to take a single hit, yet the attacker can afford to have every attacking missile take a hit except one.

For defensive volume of fire, there can be a thin line between what is sufficiently dense and what is wastefully excessive. Firing just one more interceptor per incoming missile can dramatically increase expenditure in a single engagement and result in a warship facing follow-on threats with a far more depleted magazine. But as mentioned, defensive depletion not only increases risk to the individual platform, it threatens to take that platform’s offensive fires out of the fight prematurely. The broader offensive inventory that is available for massed fires can therefore be threatened by the localized manner of defensive engagements and their especially depleting nature.

Range advantages convert to depletion advantages, where forces with longer-ranged weapons can inflict asymmetric depletion against their shorter-ranged opponents. These threatening dynamics are more probable for navies that can be up against anti-ship weapons with much greater ranges than their own, such as the current range disparity the U.S. Navy is suffering against many Chinese anti-ship missiles.

If two opposing forces have a major disparity in the range of anti-ship weapons, then the forces with less range can be forced to travel hundreds of miles while under fire before they can finally be in a position to attack. These warships can be depleting their defensive firepower while still pressing forward in an increasingly risky bid to bring their offensive firepower to bear. By comparison, the longer-ranged side will deplete far fewer defenses to make their attacks, if they have to deplete those defenses at all. Warships with a significant offensive range advantage are not only in a much better position to fire first, they can fire their salvos and then simply reverse course to keep themselves out of reach while preserving their defensive firepower. The outranged fleet can be pressing forward without much of its defensive firepower left, while the other fleet can be in the much more comfortable position of pulling back with most of its defensive firepower remaining. It is unlikely that the fleet with shorter-ranged weapons would be in a position to catch up to the opposition in many circumstances. Because of the vast distances involved and the large speed differential between anti-ship missiles and warships, it seems improbable that surface warships will run each other down on the open ocean in the age of missile warfare. 

Increased payload range can also translate into increased reload speed, where shifting more of the burden of maneuver onto the payload shortens the logistical lifeline of the platform. The longer the range of the weapon, the less the platform has to travel between its launch areas and rearmament points, shortening the episodic drops in force distribution while offering higher rates of fire. This effect is especially potent for aviation, such as how aircraft firing JASSMs at 230 miles can have much lower reload rates and availability of fires compared to aircraft firing the 1,000-mile extreme range variant of JASSM (Figure 1).³ An asymmetry in weapon range between opposing forces can translate into asymmetry in reload speeds, and make the distribution of a force more resilient against depletion than its adversary’s.

Massed Fires and Uneven Depletion Across Platform Types

As waves of massed fires ensue, the distribution of depletion across the platforms of a force can become uneven. A distributed force may prefer to prioritize its longest-ranged fires, its most common weapons, or other payloads for other reasons, which depletes the specific platforms that launch them. This sets the stage for operational tradeoffs and an evolving risk profile, since one type of platform’s fires can preserve the inventory of another’s, and different platforms have different magazine depths and timeframes for reloading. Uneven depletion can gradually shift the burden of massing fires onto platforms that must assume more risk to continue the fight, encouraging a force to carefully consider how to distribute weapons depletion across platforms over time.

The anti-ship Tomahawk will offer long range and broad magazine depth across many platforms, making it an ideal weapon for massing fires. But heavily prioritizing the use of the anti-ship Tomahawk can make surface forces and submarines among the first to deplete their anti-ship missile inventories, and where these platforms can take many days to reload and return to the fight. The weapons that can contribute the most to mass fires can suffer the most depletion, putting the distribution of the force at risk down the line.

As the fight continues and warships become more depleted, more of the U.S. burden of assembling mass fires against warships can gradually accrue to aviation because aviation can reload much faster than warships. This is especially true for carrier air wings, and carriers have the deepest magazines of all afloat combatants, potentially making them the last warships standing when it comes to remaining inventory after intense exchanges.⁴ Yet this would pose an especially concentrated posture to an adversary and force air wings to take major risks in deploying the remaining firepower. Preserving the anti-ship inventory of warships is therefore critical in forestalling a need to rely more heavily on aviation-based strikes, which would tie down numerous aircraft to muster volume of fire, pull carriers deeper into the battlespace, and assume more risk.

Yet this relationship is paradoxical. Preserving warship-based inventory can also take the form of leaning more on aviation fires earlier in the fight. Therefore a balance can be defined between the proportion of fires to come from different platform types at different phases of the fight, in order to manage how the risk profile of depletion evolves. A commander that carefully balances a combination of air wing depletion and warship depletion earlier in the fight can better delay the prospect of air wings shouldering more of the burden. Or a commander could heavily favor bombers in the opening phases, which can preserve warship-based fires for later phases, which preserves carriers. Depletion does not necessarily mean firing options have to get far worse as time goes on, depending on how commanders balance risk with regard to what combinations of launch platforms they favor depleting at different periods of the fight.

Submarines offer one of the most critical advantages in managing depletion through the highly favorable tradeoffs that come with sinking ships with torpedoes instead of missiles. The undersea domain is far less saturated with warship defenses compared to above the waterline. The cost of a missile salvo large enough to credibly threaten a group of several warships could easily exceed $100 million and require expending dozens of missiles.⁵ Credibly threatening the same group would require only several torpedoes, which could cost ten percent or less of the missile salvo.⁶ A single lethal torpedo strike can substitute for the dozens of missiles that could be required to overwhelm the same warship from above water.

By sailing far into contested littorals and laying near ports, bases, and maritime chokepoints, submarines are much more likely to be in a position to sink ships with fuller magazines compared to other platforms and deprive the adversary of inventory. However, closing the distance for torpedo strikes increases risks to submarines. The operational implications include weighing tradeoffs in the amount of risk commanders are willing to accept for their valuable submarines, versus the risk that could be incurred by depleting the broader missile magazine of the distributed force. Risking submarines in torpedo attacks can spare broader missile inventory and vice versa.

Aircraft and ground-based launchers certainly carry far fewer missiles per loadout compared to a large surface warship. Their shallower magazine depth substantially shortens the interval between launching fires and reloading, even if each of their fires is limited to a few missiles. But these platforms can typically access weapons stocks to rearm at a fraction of the time it takes a warship to do the same. Their shallow magazine depth can make their availability for fires more episodic than warships, but their episodes of depletion are not nearly as steep or prolonged. Land-based forces in the form of Chinese launchers on the mainland would have particularly more endurance than expeditionary stand-in forces that heavily depend on lengthy logistical lifelines to sustain their fires in a long fight.

The nature of uneven depletion will make for especially challenging command decisions. Commanders may face pressure to maintain depleted assets in the fight for the sake of posing some semblance of a distributed posture to the adversary. Commanders weighing such decisions would have to consider whether the adversary’s tracking of expenditure may have been accurate enough to provide the critical insight that portions of the distributed force are depleted. Operational behavior may significantly change based on one’s estimate of an adversary’s depletion and if asymmetric depletion has emerged between opposing forces.

Tracking adversary depletion is a critical operational imperative, but the desire to understand the specific composition and volume of missile salvos can place major demands on ISR and decision-making. Forces may struggle to distinguish between different types of anti-ship or anti-air missiles at long range and in the midst of battle. But knowing the type of launch platform narrows down the potential type of fires, where the tracking challenge is simplified by how certain weapons are exclusive to certain kinds of platforms. An F/A-18 firing on a warship is most likely firing Harpoons or LRASMs, and a Chinese warship firing on a ship is most likely firing YJ-83s or YJ-18s. Weapons that have longer range and are compatible with a broader variety of launch platforms will complicate the adversary’s ability to track expenditure and form estimates of depletion.

Defying Destruction and the Last-Ditch Salvo Dynamic

The adage of “firing effectively first” may be better described as striking effectively first, since two opposing naval formations can still destroy each other even if one fires after the other. In defining what it means to fire effectively first, an ideal kill of a warship or platform can include putting it out of action before it had a chance to use its offensive firepower. Similar to how it would be ideal to destroy a carrier while it is still embarking its air wing, it is ideal to destroy a warship before it has depleted its magazine of offensive missiles. This creates profound psychological and operational pressures that come into play when commanders of individual platforms and formations feel on the cusp of being destroyed. The critical phenomenon of last-ditch fires can threaten to destabilize distributed fleets and massed fires.

Commanders can be extraordinarily pressured to unleash most if not all of their offensive firepower if they believe there is a real risk of imminent destruction. Once a ship or fleet realizes that a potentially fatal salvo is incoming, enormous pressure can quickly force commanders to discharge their offensive firepower soon or else risk losing it permanently. Similar to how a carrier commander would be tempted to launch the air wing before the salvo hits the carrier, warships can make similar decisions with their missile magazines.

Last-ditch salvos are meant to deny the enemy one of the most critical benefits of firing effectively first. Launching a last-ditch salvo right before ships could be destroyed gives those offensive weapons a final chance of somehow contributing to the fight and deprives the adversary the benefit of sinking ships with fuller magazines. Last-ditch fires aim to ensure that archers are never destroyed before they can fire arrows. Concerns over losing limited weapons inventory are sharply intensified by lethal inbound salvos, making the last-ditch salvo a critical protocol for making the most of friendly losses moments before they are incurred.

A last-ditch anti-ship salvo cannot be an act of self-preservation. Commanders can be completely confident that an incoming salvo is dense enough and capable enough to overwhelm their defenses and destroy their warships. Launching their own anti-ship salvo in response is not going to change such an outcome. Anti-ship missiles cannot save warships from anti-ship missiles that are already incoming. These weapons can only save warships from anti-ship missiles that have yet to leave their magazines.

Many platforms that can threaten warships with anti-ship missiles cannot be threatened by those same missiles in return. This creates an asymmetric dynamic where some forces can enhance the effects of distribution by threatening to trigger last-ditch salvos that are futile. Since airborne aviation, submarines, and land-based forces cannot be directly attacked by anti-ship missiles, a warship launching a last-ditch salvo could very well be firing at perceived targets it can do nothing against. Even a single incoming torpedo from a submarine attack could trigger a last-ditch salvo fired in futility. Warships must strive to maintain awareness of candidate targets they can actually threaten with last-ditch salvos if a fatal attack comes from a domain they cannot effectively retaliate in.

A last-ditch salvo may be fired despite a lack of quality targeting information, since the method of simply firing down a line of bearing suggested by the incoming attack may be more than enough for a desperate warship. But warships ideally need broader situational awareness to launch effective last-ditch salvos, and especially to know whether they are under attack by a last ditch salvo themselves. If a warship does not recognize it is facing down a last-ditch salvo and simply reciprocates the attack, it could be firing on a warship with an empty magazine or even a warship that was already destroyed minutes earlier. This is even more wasteful than firing on a depleted warship, and a worthy result for warships whose final actions caused an adversary to waste precious firepower.

Last-ditch salvos are therefore a double-edged sword. This desperate act is meant to prevent precious weapons inventory from being permanently lost, yet this desire can be manipulated to prompt wasteful fires. An adversary can be made to take self-defeating actions in the crucial battle of nerves that infuses salvo warfare.

The simple appearance of an inbound volume of fire can be enough to trigger last-ditch firing protocols. Weapons with longer range and waypointing ability will have more opportunity to feint attacks on the way to their true target, multiplying the combat potential of salvos. If a weapon has enough range, attacking salvos may be waypointed to appear to threaten multiple targets in succession and provoke last-ditch fires from each (Figure 2).

Figure 2. A waypointed salvo triggers last-ditch fires from multiple formations by feinting attacks along the way to its true target. (Author graphic via Nebulous Fleet Command) 

The U.S. may eventually have a substantial advantage in this regard by fielding a cruise missile with especially long range. The Tomahawk has enough range to where a salvo can threaten multiple naval formations through waypointed feints, even if those formations are distributed across hundreds of miles. If several Chinese naval formations are concentrated within 300 miles so they can mass YJ-18 missiles, then it becomes even more feasible to waypoint Tomahawks to trigger last-ditch fires within this radius. If one side’s naval formations have to concentrate within shorter distances to mass their fires, they become more susceptible to this waypointing tactic than their opponents, and they may not even have the range to launch viable last-ditch salvos at all.

Salvos used to trigger last-ditch fires may have to risk a degree of attrition by allowing themselves to be seen by warships. Networked missiles could coordinate pop up maneuvers to rise above the horizon and make themselves known, but only briefly enough before they can be struck by defensive fires. Otherwise the salvo could suffer enough attrition that it loses both its psychological and kinetic potency. Decoy weapons that can project the signatures of multiple aerial contacts, such as the ADM-160 MALD, can be used to inflate the appearance of mass while reducing the ability of defensive fires to chip away at the salvo.⁷

Posing the appearance of significant mass may not be a hard requirement for inducing last-ditch fires from a target. There may be a significant disparity in the volume of fire required to actually kill a platform, versus the volume of fire that is enough to manipulate it into firing prematurely. This disparity can stem from commanders being uncertain about the capability of enemy salvos or their ability to defeat them, or the strain of combat operations taking its toll on decision-making. The last-ditch dynamic can therefore magnify the tactical value of salvos that lack enough volume of fire to destroy targets. Commanders that are limited to local awareness may struggle to differentiate between a small salvo that was only launched as a standalone attack, versus a small salvo that is a harbinger of incoming mass fires. A small salvo can leverage these uncertainties to score outsized tactical benefit by triggering last-ditch fires despite not being able to actually threaten the target. 

Even if a salvo cannot strike a target due to limited range or other constraints, it may still provoke emissions, signatures, and other reactions that could be exploited. Commanders may struggle to distinguish between different types of incoming missiles in real time, where last-ditch salvos consisting of low-capability, short-range, or non-anti-ship weapons can still manipulate reactions. A warship launching a last-ditch salvo could certainly fire its land-attack cruise missiles toward an enemy warship, who either can’t tell the difference or won’t take the chance. The prospect of wresting any sort of non-kinetic benefit can encourage platforms under heavy attack to launch last-ditch salvos regardless of capability or volume of fire.

And non-kinetics can prompt last-ditch fires themselves. Actions such as heavy jamming, blinding attacks against networks, aggressive posturing, and other methods that could be interpreted as a prelude to an imminent attack could also provoke last-ditch salvos. Last-ditch fires can be triggered by much more than just other fires.

The act of firing last-ditch salvos is extremely sensitive to timing given how warship launch cells are often carrying both offensive and defensive firepower, and how some cruise missiles require a minimum amount of lead time to be programmed for launch.⁸ A warship under attack from a subsonic anti-ship missile fired at a range of 250 miles has barely more than 20 minutes to react. And this assumes the target warship has knowledge of the launch. If the warship becomes aware of the incoming salvo only after it crosses the horizon, it can have roughly two minutes or less to prosecute an intense anti-air engagement while simultaneously discharging the whole of its offensive firepower in a last-ditch salvo. Those final moments would be characterized by an intense outpouring of the ship’s firepower in all-out offensive and defensive warfare. But these vast volumes of firepower would be bottlenecked by the rate of fire, of how many missiles can be fired by a warship’s launch systems in short periods of time. The volume of outgoing offensive and defensive firepower would be diminished as missiles of both types are primarily being fired from the same sets of launch cells, making them compete with each other for brief launch windows.

These challenges can be mitigated by having situational awareness over sea-skimming spaces that go beyond the radar horizon of a warship. Aircraft can provide early warning of incoming salvos and help warship commanders determine whether they must initiate a last-ditch salvo. Effective warning can allow commanders to discharge their last-ditch salvos early enough so that offensive missiles are not competing with defensive missiles for launch windows when it comes time for the warship to defend itself. In any case, warship commanders should strive to have a variety of pre-programmed responses at the ready so they can initiate last-ditch fires as fast as possible, and to have the subjective tactical judgement to know when it is time.

Warships under attack could be forced to fire their final salvos alone and in isolation from the broader distributed force. Yet last-ditch salvos may hardly be enough on their own to overwhelm concentrated defenses. This can put pressure on other combatants and commanders to add contributing fires in the hopes of growing enough volume to credibly threaten targets. A cascading domino effect could threaten to unravel a distributed force’s firepower as last-ditch salvos prompt hasty contributing fires from other platforms. The pressured nature of last-ditch salvos will exacerbate the timing challenges associated with combining fires and potentially rule out a variety of options for growing the volume of fire.

A commander of a distributed force must weigh the risks of attempting to combine fires with a last-ditch salvo. A last-ditch salvo may force a commander’s hand in adding contributing fires to a salvo that was fired on insufficient targeting data, lacks the volume to penetrate defended targets, or features other deficiencies. A commander could hold off on launching contributing fires, conserve the inventory of weapons, and allow the last-ditch salvo to play out on its own. But this may come at the risk of failing to support a salvo that could have effectively put opposing warships out of action if it had received just enough outside fires to tip the scales and cross the thresholds needed to overwhelm defenses. Commanders have to be ready to weigh these options as missile exchanges unfold in real time, and decide if a last-ditch salvo should remain a standalone attack, or leverage it through adding contributing fires.

Conclusion 

As distributed forces unleash massed fires against one another, their desire to decisively overwhelm the opposition will be tempered by the need to minimize depletion. Depletion can threaten to break naval operations and yield major advantage to an adversary. Effectively massing fires from distributed forces can help manage depletion, but the need to achieve overwhelming volume of fire will make this risk a pervasive consideration at all levels of warfare.

Part 5 will focus on missile salvo patterns and maximizing volume of fire.

Dmitry Filipoff is CIMSEC’s Director of Online Content and Community Manager of its naval professional society, the Flotilla. He is the author of the “How the Fleet Forgot to Fight” series and coauthor of “Learning to Win: Using Operational Innovation to Regain the Advantage at Sea against China.” Contact him at Content@Cimsec.org.

References

1. For weapon production lead times, see:

“Department of Defense Fiscal Year (FY) 2023 Budget Estimates,” Navy Justification Book Volume 1 of 1 Weapons Procurement, Navy, Page 2 P-1 Line #7, (PDF pg. 94), April 2022, https://www.secnav.navy.mil/fmc/fmb/Documents/23pres/WPN_Book.pdf.

Seth Jones, “Empty Bins in a Wartime Environment: The Challenge to the U.S. Defense Industrial Base,” Center for International and Strategic Studies, pg. 14, January 2023, https://csis-website-prod.s3.amazonaws.com/s3fs-public/2023-01/230119_Jones_Empty_Bins.pdf?VersionId=mW3OOngwul8V2nR2EHKBYxkpiOzMiS88. 

2. For one example, a warship on a one-way trip and traveling at 20 knots would take nearly two weeks to reach the Philippine Sea from U.S. naval infrastructure in San Diego. This assumes a straight line path, which may be less realistic under wartime conditions.

3. For JASSM range, see:

“AGM-158 Joint Air-to-surface Stand-off Missile (JASSM),” U.S. Air Force, https://www.af.mil/News/Art/igphoto/2000420243/.  

For extreme-range JASSM variant, see:

Brian A. Everstine, “USAF to Start Buying ‘Extreme Range’ JASSMs in 2021, Air & Space Forces Magazine, February 14, 2020, https://www.airandspaceforces.com/usaf-to-start-buying-extreme-range-jassms-in-2021/.

4. Hon. John F. Lehman with Steven Wills, “Where are the Carriers? U.S. National Strategy and the Choices Ahead,” Foreign Policy Research Institute, pg. 67, 73, September 9, 2021, https://www.fpri.org/wp-content/uploads/2021/09/fpri-where-are-the-carriers-.pdf. 

5. At an average unit cost of $3.5 million per missile, a combat credible salvo of about 30 LRASMs yields a volume of fire that costs in excess of $100 million.

For LRASM unit cost, see:

“Department of Defense Fiscal Year (FY) 2023 Budget Estimates,” Navy Justification Book Volume 1 of 1 Weapons Procurement, Navy, Page 1 of 10 P-1 Line #16, (PDF pg. 261), April 2022, https://www.secnav.navy.mil/fmc/fmb/Documents/23pres/WPN_Book.pdf.

6. MK 48 MOD 7 torpedoes have an average unit cost of around $5 million, but have far less of a requirement to be salvoed in large numbers because of the less saturated nature of undersea warship defenses.

For MK 48 MOD 7 torpedo cost, see:

“Department of Defense Fiscal Year (FY) 2023 Budget Estimates,” Navy Justification Book Volume 1 of 1 Weapons Procurement, Navy, Page 1 of 16 P-1 Line #27, (PDF pg. 351), April 2022, https://www.secnav.navy.mil/fmc/fmb/Documents/23pres/WPN_Book.pdf.

7. “U.S. Airborne Electronic Attack Programs: Background and Issues for Congress,” Congressional Research Service, pg. 16-17, May 14, 2019, https://crsreports.congress.gov/product/pdf/R/R44572. 

8. General Accounting Office, “Cruise Missiles: Proven Capability Should Affect Aircraft and Force Structure Requirements,” GAO/NSIAD-95-116, April 1995, pg. 35-36, https://www.gao.gov/assets/nsiad-95-116.pdf. 

Newer Tomahawk variants than those discussed above have considerably shorter launch preparation times. See:

“Tomahawk,” Missile Threat CSIS Missile Defense Project, last updated February 23, 2023, https://missilethreat.csis.org/missile/tomahawk/ 

and 

Rear Admiral Edward Masso (ret.), “On The Tomahawk Missile, Congress Must Save The Day,” Forbes, June 10, 2015, https://www.forbes.com/sites/realspin/2015/06/10/on-the-tomahawk-missile-congress-must-save-the-day/?sh=7b86cc956bad. 

Featured Image: September 3, 2005 – U.S. Navy Sailors aboard the USS Fitzgerald (DDG 62) inspect the MK 41 Vertical Launching System (VLS). (Photo via U.S. National Archives)