The increasing range and potency of A2AD defence, particularly the anti-ship missile threat, is leading navies to reconsider how individual ships as well as the battle group can be better defended.
The expansion of Anti-Access Area Denial (A2AD) zones at sea with the deployment of longer-range surveillance systems; air- ship- and land- based anti-ship missiles; cruise missiles, ballistic missiles and unmanned systems means that threats to the safety of deployed large-scale naval forces has increased substantially. Hypersonic missiles are also under development that will further complicate the ability to defend naval platforms.
China has been at the forefront of expanding its A2AD zone into the Western Pacific as a way of keeping United States Navy (USN) and other allied fleets away from its littoral zones. The farther to sea that China can keep its potential opponents, the less power they can exert onto the Chinese mainland. The People’s Liberation Army Navy (PLAN) has been recognised as the largest in the world, by a count of ship numbers, and fields an increasing number of larger, more sophisticated, ocean-going warships that can host anti-ship missiles.
The PLA Rocket Force backs up the PLAN with an inventory of thousands of different missiles that can be brought to bear against a fleet approaching China’s littorals. Should any large scale conflict break out between China and the US, the latter’s fleet will be a primary target for Chinese forces.
Anti-ship missiles have not been used en masse in naval conflict, but their lethality has been proven since the first ship, INS Eilat, was sunk by Egyptian missiles during the Yom Kippur War in 1973. Almost a decade later during the Falklands War in 1982, British warships were sunk by air-launched Exocet cruise missiles and air-launched bombs. Today the proliferation of long-range missiles means these weapons can be launched from longer distances. The difficulty for the USN is that if its ships are detected then it could be vulnerable to large salvos of missiles that may overwhelm it fleet defences.
Mark Cancian, a senior adviser on International Security Programs at the Centre for Strategic and International Studies, told AMR that the USN is pursuing four methods of fleet protection to increase its chances of surviving a large-scale missile attack. The first is providing evolutionary upgrades to its existing fleet; the second is to increase the USN’s missile inventory; the third is to implement its Distributed Maritime Operations (DMO) concept, while the fourth is the introduction of unmanned systems.
Ship enhancements
Upgrades to the USN’s fleet include the addition of new sensors and weapons that improve air and missile defence. The new Arleigh Burke-class Flight III destroyers will be equipped with the Raytheon AN/SPY-6(V)1 Air and Missile Defense Radar (AMDR), a new AN/SLQ-32(V6) SEWIP Block 2 Electronic Warfare (EW) suite and the Aegis Baseline 10 combat system. Aegis integrates a ship’s sensors and weapons to defend against anti-ship missiles and has been upgraded over the decades to improve capabilities as new threats and technologies emerge. Comprising of a S-band and X-band radar and a controller suite, the SPY-6 radar can simultaneously detect airborne and sea threats, it is more sensitive offering an improved ability to detect and track more targets at range. It can also conduct electronic attack.
In June 2023, shipbuilder Huntington Ingalls Industries (HII) delivered the first Flight III destroyer USS Jack H. Lucas (DDG 125) to the Navy. The Flight IIIs will eventually replace the Ticonderoga-class cruisers as the primary air defence ship for USN’s carrier strike groups. As well as new variants of the Arleigh Burke-class coming on stream, the USN is also getting new Constellation-class of frigates are being introduced that are a more capable vessel in comparison to the Littoral Combat Ship (LCS) classes.
Meanwhile air defence missiles, such as the Raytheon RIM-162 Evolved Sea Sparrow Missile (ESSM), are being upgraded. The Block 2 variant will improve the performance of the missile against fast, low altitude and highly manoeuvrable anti-ship cruise missiles (ASCMs). It will do this by replacing the guidance section with a dual mode Active/Semi-Active X-Band seeker.
According to USN Budget FY2024 data, initial operating capability was completed in December 2021 and full rate production ESSM Block 2 rounds will be delivered from 2025. “Full Operational Capability with Optimised implementation for Aegis to make full use of capability resident in the missile, and a Functional implementation for SSDS [Ship Self Defense System] platforms is scheduled for 2025,” it said.
Missile focus
As part of the USN’s Multiyear Procurement (MYP) strategy for increasing its missile inventory it will start to place larger orders for the Raytheon RIM-174 Standard Extended Range Active Missile (ERAM), or Standard Missile 6 (SM-6) missile. According to the USN the SM-6 Block I/IA/IB missiles provide an extended range engagement capability to provide air superiority and protection against a full spectrum of crewed-fixed wing and rotary wing aircraft, unmanned aerial vehicles, and land attack and anti-ship cruise missiles.
SM-6 is the primary extended-range air defence weapon for USN’s cruisers and destroyers equipped with Aegis and it will likely be fitted to future combatants as well. The funding profile for the SM-6 Block IA is through a five-year MYP that begins in FY2024 and completes in FY2028.
Cancian said that the Ukraine War has seen stockpiles of smart weapons used up very quickly, so the focus on increasing weapons inventories will ensure that offensive and defensive operations can be sustained for medium and long-durations. By deepening the missile inventories and magazines it provides more capability to handle air and missile threats.
However, expanding the industrial base to produce larger numbers is difficult to achieve short term. The USN budget FY 2024 includes Large Lot Procurement funding of $169 million for industrial base investment. This will allow an increase in annual production of SM-6 missiles from the existing rate of 125 per year to 300 by FY2028, at the end of the current MYP. The provision of more SM-6 missiles will provide an important theatre-level capability to protect ships and ground manoeuvre forces.
Meanwhile at the ship defence level there are also increased orders for the Raytheon Rolling Airframe Missile (RAM), which is fired from the Mk49 guided missile launching system and the Mk15 SeaRAM anti-ship missile defence system. RAM is used to defend against ASCMs with RF/IR guidance and an optical proximity and contact fuse. RAM Block 2 is also capable of defeating highly manoeuvrable threats and low-probability of intercept threats. From current orders of 70 (in FY2022) and 100 (in FY2023) from FY2024 these will reach 120 per year.
Maturing concepts
The third effort is to make the DMO concept work in practise. Instead of USN forces concentrating and operating close together in formation such as in a carrier strike group or amphibious task group, DMO calls for a wider dispersal of its platforms, which will make them harder to detect and target.
In its Large Scale Exercise 2023 (LSE 2023) in August 2023, the USN conducted a series of operations and testing to prove elements of the DMO concepts. This included measuring how far ships could operate away from each other across a broader area of ocean than they have been used to in the past, whilst also remaining coordinated.
“The idea behind this exercise was to see how far you can be spread out and still be connected and act as a unified command [and] still focus their effects without being concentrated in their individual locations,” Cancian said, “And as you spread out your sensors you have a better perspective of your battlespace but not so far apart that you are isolated.”
The USN stated that LSE 2023 brings together the combined firepower of the Navy and Marine Corps team across six maritime component commands, seven numbered fleets, and 22 time zones.
All the commands and units involved were spread out across the world but could plug into a virtual network and become a part of the exercise. It proved that units distributed on a global level are able to communicate, act and conduct operations as if there were in one fleet in a single area of operations. For DMO to work ships and other crewed and unmanned assets need to be connected by robust communications links to allow them to pass ISR information and targeting data to each other in order to generate mass fires against a target from a variety of dispersed locations.
Lieutenant General Brian Cavanaugh, commander, Marine Forces Command stated: “Conducting these operations in a live, virtual, and constructive manner is key. From the tactical end where we have the sailors and marines doing operations on the ground or at sea, all the way up to the command and control aspect, our ability to synchronise and conduct those operations are critical.”
Speaking to reporters at the conclusion of LSE 2030, Commander US Fleet Forces Command, Admiral Caudle stated that communications networks were attacked using cyber, space, information warfare, networks, C3, Command & Control communications, as part of the exercise itself “to actually test specific things and how we devolve, how we do continuity of operations, how we shift to other networks, how we test things like Virtual Secure Enclave, where we go through a very secure communication system.”
Commander of the US Pacific Fleet, Admiral Samuel Paparo told reporters that DMO “gives us the ability to mass fires under the principles of expanded manoeuvre, and that has been enabled by our ability to disaggregate sensor, shooter, and platform, to be able to achieve mass of fires on particular centres of gravity while dispersing and operating formations more dynamically.”
Unmanned capability multipliers
The USN’s fourth fleet protection effort is the focus on introducing more unmanned systems. The DMO concept won’t work without the deployment of larger numbers of unmanned surface vessels (USVs) and unmanned underwater vessels (UUVs). The USN’s main two USV projects that will contribute to DMO are the Large Unmanned Surface Vehicle (LUSV) and the Medium Unmanned Surface Vehicle (MUSV) projects.
A Congressional Research Service (CRS) paper ‘Navy Large Unmanned Surface and Undersea Vehicles: Background and Issues for Congress’, published on 5 September stated that these are part of an effort “to shift the Navy to a more distributed fleet architecture, meaning a mix of ships that spreads the Navy’s capabilities over an increased number of platforms and avoids concentrating a large portion of the fleet’s overall capability into a relatively small number of high-value ships.”
Cancian said the USN does not have any programmes of record for the procurement of systems, but these two USV projects represent a considerable amount of experimentation that is underway. “The conceptual design is to team manned surface ships with unmanned to increase survivability,” he said, “The concept is that unmanned surface vessels would act like pickets with sensors and maybe shooters further out to detect threats in advance so that the crewed ship would not be as vulnerable.”
Picket ships are usually positioned in advance of the larger fleet or task force in a screening role it means these vessels will come into contact with enemy forces first. This makes those ships vulnerable to attack. During the Falklands War, it was the screening ships of the UK Royal Navy that were hit by anti-ship missiles and bombs. During the Second World War casualty rates among USN’s picket ships were significantly higher as they became victim to Japan’s kamikaze aircraft.
“At Okinawa, the USN put picket ships out in front to act as sensors, and also shooters. One of the concepts for unmanned operations is to do the same thing, to go out in front as pickets to spot incoming attacks, but also to engage as well if they are armed,” Cancian said.
The LUSV will have more offensive capabilities whilst the MUSV will have ISR as its main tasking. The USN FY2024 budget states that LUSV “is a key enabler of the Navy’s DMO concept, which includes being able to forward deploy and team with individual manned combatants or augment battle groups. LUSV will complement the Navy’s manned combatant force by delivering increased readiness, capability and needed capacity at lower procurement and sustainment costs and reduced risk to sailors.”
The LUSV is anticipated to be a 1,000-2,000 tonnes 200-300 feet (60-90 metres) long corvette-sized ship that would host modular payloads including anti-surface warfare capabilities fired from a 16-32 cell vertical launch system. According to the FY2024 budget the first LUSV is to be procured in FY2025 for $315 million with two slated for FY2026 for $522.5 million with three each in FY2027 and FY2028 for $722.7 million and $737.2 million respectively.
The MUSV is also a key enabler of DMO. “MUSVs will be capable of weeks-long deployments and trans-oceanic transits, and operate aggregated with Carrier Strike Groups (CSGs) and Surface Action Groups (SAGs), as well as have the ability to deploy independently,” the USN stated.
MUSV will be a 500 tonne, 45-90ft (14-27m) long patrol craft that will be specifically designed to host ISR payloads and EW systems. Under a contract with L3Harris signed in July 2020 the delivery of an initial prototype MUSV is expected in Q4 FY2024, which will be followed by developmental and operational testing. Additional units could be bought under available contract options.
In the meantime, the budget provides $117.4 million in R&D funds for LUSV with $85.8 million for the MUSV programme with an additional $176.3 million for LUSV/MUSV enabling capabilities.
Having unmanned vessels in the picket role would be valuable as a way of expanding fleet ISR capabilities and protecting the fleet without exposing sailors to a high level of threat. In future these capabilities would give the USN some confidence of being able to operate within China defensive bubble, however, Cancian said it will still be some time before large numbers of unmanned vessels will be seen operating in this capacity.
As A2AD zones become more sophisticated presenting an increased risk to US freedom of operations, the USN is once again leveraging its technological edge and moving the goal posts. Within the next decade new USN platforms will be delivered with more capable defensive equipment, missile inventories and production capacity will increase, DMO will become a reality and unmanned systems will enter service – all of which will give the USN the ability to operate in high risk A2AD zone and retain control of seas.
by Dr. Lee Willett
