The US Navy is attempting to transition from a force composed entirely of large, manned platforms to one with a larger proportion of small manned and unmanned ships, aircraft, and undersea vehicles. However, with budgets unlikely to grow substantially during the 2020s, freeing up funds to make this shift will result in the US fleet initially shrinking as numerous surface combatants and submarines built in the waning days of the Cold War retire without immediate one-for-one replacements. By the 2030s Navy leaders intend to begin growing the fleet as new unmanned ships and aircraft enter the force, along with hypersonic weapons and lasers to improve the fleet’s lethality and survivability, and capabilities developed through Project Overmatch that provide decision-making advantages.
3.1 US Navy strategic and doctrinal thinking
The US Navy and Marine Corps face growing challenges ranging from great powers China and Russia to regional threats such as Iran and North Korea, all of whom seek to undermine their neighbours’ stability and revise geopolitical relationships in their favour. Despite the impact of the Covid-19 pandemic and resulting economic downturn, each of these potential adversaries continued to improve its military capabilities, especially the number and reach of precision missiles able to strike US allies and slow or prevent intervention by US naval forces. Supported by commercial and military surveillance networks in every domain, weapons based on adversary territory could threaten US and allied ships, troop formations, and aircraft hundreds of miles away. China fields the most capable of these networks.1
Russian and Chinese submarines pose one of the most significant threats to US naval forces in the open ocean, but for different reasons. The Russian Navy’s submarine force is relatively small, but its nuclear-powered attack submarines (SSN) are on par with their US counterparts in terms of quieting, sonar, systems, and weapons. Russian SSNs could evade US and allied anti-submarine warfare efforts and threaten attacks targets ashore or at sea.2 In contrast, the PLA Navy’s (PLAN) fleet is comprised predominantly of diesel-electric (SS) and air-independent propulsion (SSP) submarines – but it is rapidly modernising. In a confrontation, the PLAN’s growing numbers of quiet conventional submarines could overwhelm ASW capabilities.3
The US Navy is responding to the challenge of more contested operating environments with distribution and mobility as described in its Distributed Maritime Operations (DMO) concept, which parallels US Marine Corps concepts for Expeditionary Advanced Base Operations (EABO) and stand-in forces (SIF). These concepts align with the new US Joint Warfighting Concept, which employs “expanded manoeuvre” to disaggregate forces for resilience, aggregates their effects on offense, and relies on decision support and interoperability tools from the DOD’s Joint All-Domain Command and Control (JADC2) initiative to build and execute effective force-wide courses of action.4 Rather than being a concept or programme itself, JADC2 is a coordinated effort among the US military services to improve their ability to connect the best shooter, sensor, and commander for a given task and provide the analytics to gain decision superiority.
Command and control is the most important aspect of the US Navy’s changing conceptual approach. Commanders of distributed ships and troop formations rely on fleet commanders’ Maritime Operations Centers ashore for intelligence, planning, and direction – a dependency that would increase during conflict.5 However, opponents like China could disrupt long-range communications, requiring the Navy to develop C2 processes and architectures that adapt to communications availability, rather than trying to build networks that can allow fleet commanders to direct operations under all wartime conditions. The Navy is pursuing agile C3 as part of its JADC2-related experimentation effort, Project Overmatch.
3.2 US Navy technological/innovation priorities
The Navy budget is unlikely to grow substantially. As a result, new concepts such as DMO, EABO, and SIF that require more distributed operations will drive the fleet to become more heterogeneous, incorporating a growing number of lower cost and less-multifunctional manned and unmanned vessels and aircraft alongside large traditional multisession platforms.6
Project Overmatch is intended to integrate for an increasingly heterogeneous fleet and is the Navy’s top innovation priority.7 Managed by the Navy Information Warfighting Center (NAVWAR), Project Convergence includes actions to connect existing DoD tactical networks such as Cooperative Engagement Capability (CEC), Link-16, and Tactical Targeting Network Technology (TTNT), which were already being integrated through the Navy Integrated Fire Control programme, with newer networks such as the Multifunction Advanced Datalink (MADL) on F-35 aircraft and datalinks used by the Navy’s growing family of unmanned vehicles.8 Project Overmatch also includes C2 and decision support systems needed to manage the complexity associated with more distributed, heterogeneous units and tailored force packages.9
Whereas C3 leads the Navy’s technical and operational innovation efforts, the service’s highest acquisition priority is the Columbia-class SSBNs. Built to replace aging Ohio-class boats commissioned during the Cold War and now reaching their fourth decade of service, Columbia SSBNs will incorporate several new technologies. In addition to adopting sensor and combat system advancements developed for the Virginia attack submarine programme, Columbia SSBNs will use electric propulsion and a new system of control planes.10 In part due to its new technologies, the Columbia programme is challenged to remain on schedule, leading the Navy to investigate ways to operate Ohio-class submarines beyond their already extended 42-year service lives.11
The Navy surface and air warfare communities are also pursuing priority programmes in the DDG(X) destroyer and Next Generation Air Dominance (NGAD) family of manned and unmanned aircraft, respectively. The DDG(X), set to arrive in the mid-2030s, is intended to replace Ticonderoga-class cruisers that will retire this decade. DDG(X) would provide naval forces with improved air defence using a larger missile battery and high-energy laser as well as greater offensive reach with hypersonic boost-glide missiles.12 The Navy is currently pioneering these technologies on existing surface ships. The FA-XX is intended to debut in the mid to late-2030s and replace the Navy’s aging fleet of F/A-18 E/F Super Hornets. A sixth-generation fighter, the FA-XX would bring greater range and survivability compared to the F-35 and F/A-18. However, in a tight budget environment, these programmes will likely receive less attention and resources than Columbia or JADC2.
3.3 Systems under development in the maritime domain
Although not a national priority like the Columbia SSBN, the Navy’s Constellationclass guided missile frigate (FFG) programme recently began construction, with a plan to build at least 20 of the ships over the next decade. The Constellation will focus on ASW and other escort missions to free up Arleigh Burke-class guided missile destroyers (DDG) for missile defence and strike warfare. Since it is to be equipped with the CAPTAS-4 towed low-frequency active sonar, the Constellation will also likely be the Navy’s best platform for tracking quiet enemy submarines.13
At about half the cost of a DDG, the Navy intends FFGs to mitigate reductions in the surface fleet’s size as Cold War-era cruisers and DDGs retire during the 2020s. And the ability to build more FFGs will gain importance if the Navy follows through on plans to succeed the Burke-class DDGs by the end of this decade with a larger and more expensive DDG(X), which will incorporate new hypersonic and laser weapon technologies.
Since 2015, the Navy has fielded and tested prototype laser weapon systems (LaWS) on amphibious ships USS Ponce and Portland capable of countering UAVs surface craft. The service plans to install the high-energy laser with integrated optical dazzler and surveillance (HELIOS) system on USS Preble in 2023, which could be scaled to 120 kW to defeat some missiles or rockets.14Longer-term, the Navy’s High Energy Laser Counter-ASCM Program (HELCAP) is developing a 300-kW laser. By relying on electrical power instead of surface-to-air missiles, HELCAP would increase the missile defence capacity and survivability of surface combatants and is planned for installation on some Flight III Burke DDGs.15
In concert with the US Army, the Navy is developing a common conventional prompt strike (CPS) hypersonic missile. While the Army version would be deployed from mobile, ground-based launchers, the Navy intends to initially field its CPS weapons on the service’s three Zumwalt-class DDGs by 2025.16 CPS missiles would also be introduced Block V Virginia-class SSNs that include Virginia Payload Modules starting in 2028.17 As a boost-glide weapon, CPS uses a ballistic missile to lift its hypersonic glide vehicle warhead into the upper atmosphere, which then drops to the target using gravity to reach speeds of more than Mach 5, using speed and manoeuvrability to evade enemy air defences.
The Navy is pursuing modest improvements to its anti-submarine warfare (ASW) capabilities. To increase inventories, the service restarted production of the venerable Mk-48 submarine-launched heavyweight torpedo, the newest version of which incorporates digital sonar processing and improved guidance and control systems.18 To help submarines defeat incoming torpedoes and provide ASW aircraft greater weapons capacity, the Navy also developed the Compact Rapid Attack Weapon (CRAW), a torpedo about 1/3 the size of the Mk-54 carried by surface ships, MH-60R Seahawk helicopters, and P-8A Poseidon fixed-wing aircraft.19 With the MH-60R and P-8A both finishing production within the last few years, the Navy is not planning to start new maritime patrol aircraft until the mid-2030s.
Due to the procurement and operating costs of its manned surface and undersea platforms, Navy leaders plan for unmanned vehicles to help achieve a more distributed fleet that can conduct operations at a greater scale and tempo compared to today. To that end, the Department of the Navy’s 2021 Unmanned Campaign Plan prioritises efforts to develop concepts for manned-unmanned teaming, the digital infrastructure to manage unmanned system operations, and processes for fielding unmanned systems to address important operational problems. However, the Navy has been slow to introduce unmanned systems beyond intelligence, surveillance, and reconnaissance (ISR) systems such as small RQ-21 Blackjack or Scan Eagle shipboard UAVs, Mk-18 mine hunting unmanned undersea vehicles (UUV), oceanographic SHARC wave gliders, and the large MQ-4C Triton UAV.20
After multiple false starts over the previous decade, the Navy started an unmanned carrier-based aircraft programme in 2018, the MQ-25A Stingray.21 Each Stingray refuelling aircraft can extend the reach of two carrier-based strike fighters to about 1,000 nm, relieving F/A-18 E/F Super Hornets of this mission and freeing them up for combat operations.22 However, to refuel all its available strike-fighters each carrier air wing would need to include 15 MQ-25As, rather than the 5-9 described in the most recent Navy plans.23 Although the Navy’s current plans would result in only about 10 percent of each carrier air wing being comprised of unmanned aircraft, Navy aviation leaders intend to increase that fraction to 60 percent by the late 2030s with the NGAD family of systems.24
Undersea, the Navy is pursuing a family of systems in four size ranges. At the high-end, the Orca extra-large UUV (XLUUV) is intended to be launched from piers or large amphibious ships but has encountered problems in testing that will likely constrain the reach and endurance of its operations. As a result, the Navy is planning to use it mainly for deploying mines and small UUVs (SUUV) rather than longer surveillance missions. Funding for the Snakehead large displacement UUV (LDUUV) was truncated by the Navy in its Fiscal Year (FY) 2023 budget proposal but is likely to be restored by the US Congress. The Navy sought to stop work on LDUUV because its deployment concept of being carried in dry-deck shelters on the back of SSNs and guided missile submarines (SSGN) was impractical, competed with the needs of special operations forces, and delayed testing on the programme.25
The Navy has had more success with its medium UUV (MUUV) programmes, which are designed to be launched from ships, boats, or torpedo tubes. The Mk-18 Mod 1 and Mod 2 have been in service for more than a decade and will be replaced by the Knifefish MUUV. Eventually the Razorback MUUV will provide a common MUUV platform for mine-hunting and other missions, including conducting ISR and other missions from submarines using torpedo tube launch and recovery.26 However, because each MUUV takes up a torpedo stow, the submarine force is unlikely to use it extensively and the MUUV will be operated more often from surface ships or shore.
The Lionfish SUUV is the Navy’s newest UUV programme. At 10 inches or less in diameter, the Lionfish could be small enough to be deployed by submarine countermeasure systems, XLUUVs, and potentially aircraft sonobuoy launchers. SUUV missions would include ISR but could also include acting as sonar decoys or jammers.27
Like UUVs, the Navy plans to field several sizes of unmanned surface vessels (USV), also with mixed results. Large USVs (LUSV) are being developed to carry missile magazines to augment manned surface combatants. The Navy has taken delivery of three prototype LUSVs from the Office of the Secretary of Defence’s Strategic Capabilities Office (OSD SCO), with one more under construction. Insights from prototype experiments will inform studies of purpose-built LUSVs underway at six design yards.28
Medium USVs (MUSV) are intended to conduct reconnaissance and counterreconnaissance missions by carrying passive radiofrequency and infrared sensors, EW jammers and decoys, or radar illuminators to support multistatic detection by manned platforms carrying radar receivers.29 The Navy has built three MUSV protypes, which have been used in multiple experiments and exercises. However, Navy leaders suggest the results show MUSV missions could be done more affordably by smaller USVs, which may lead to the programme being cancelled or truncated.30
Nearly all the Navy’s small USVs are experimental, such as the Saildrone USVs being used in the Middle East by Task Force 59 (TF-59).31 Although TF-59’s effort may eventually field more than 100 USVs across the Persian Gulf, Arabian Sea, and Red Sea, these commercial systems lack the hardened communications of military vehicles or sensors such as sonar arrays and sophisticated signals intelligence devices. The TF-59 unmanned force may therefore be well-suited, but unique, to the Middle East and not an approach the Navy would replicate elsewhere such as the Atlantic or Western Pacific. The small mine countermeasures (MCM) USV, which reached initial operating capability in 2022, is the Navy only formal USV programme of any size.32 Although initially designed to tow influence sweep systems, the MCM USV could conduct ISR, EW or other missions in the future.
Despite its challenges in fielding unmanned vehicles, the Navy will likely have by 2030 about a dozen prototype MUSVs and LUSVs. Formal programmes will be established by the mid-2020s for each platform, along with the Orca XLUUV, Razorback MUUV, and Lionfish SUUV that began work in 2022. According to the Navy’s most recent shipbuilding plan, the service plans to field between 89 and 149 unmanned vessels by 2045, although the exact mix will depend on technical and operational considerations as the programmes evolve.33
3.4 The US Navy’s approach to multi-domain and C3
As a multi-domain service, nearly all the Navy’s platforms exert effects across domains. For example, SSNs are now deploying EW systems to generate effects in the electromagnetic spectrum, as well as missiles to launch attacks against targets at sea or ashore. Aircraft like the P-8A launch and manage sonobuoys such as the Multistatic Active Coherent (MAC) system that can detect and track even the most capable opposing submarines. And FFGs and DDGs both can conduct ASW, air defence, and strike warfare.
In addition to the hypersonic prompt global strike missile, the Navy surface force is pursuing upgrade to the Tomahawk land-attack missile and Standard Missile (SM)-6 air defence interceptors enable them to conduct maritime strike.34 The submarine force is also planning to leverage the upgraded Maritime Strike Tomahawk to enable long-range anti-ship attacks from their vertical launch tubes. Between now and 2030s, the surface force is planning to develop a new Offensive Anti-Surface Warfare weapon to replace the Cold War-era Harpoon anti-ship missile and complement the Tomahawk and SM-6.35
With systems operating in the air, on the water, undersea, and ashore, the Navy’s C3 architectures and processes are critical to connecting and orchestrating capabilities across domains. The service’s efforts under Project Overmatch are extending its C3 capabilities to a growing number and variety of force packages to address fleet commanders’ operational challenges. Supporting initiatives, such as the Rapid Autonomy Integration Lab (RAIL) are building the digital infrastructure needed to coordinate unmanned systems across domains, in some cases using common control systems.36 A combination of C3 capabilities and automation will be essential for Navy leaders to fulfil their vision of a larger, and increasingly unmanned, fleet.