Royal Australian Navy Explores Autonomy and Optional Crewing: Eyes LUSV as Potential LOSV Solution


By Gregor Ferguson

The Australian Department of Defence’s response to the Royal Australian Navy surface fleet review, Enhanced Lethality Surface Combatant Fleet, published in February, announced the RAN would field six Large Optionally Manned Surface Vessels (LOSVs) from the 2030s to carry missile launch systems.

Interestingly, the RAN program closely resembles a similar but far more advanced one in the United States, the US Navy’s Large Unmanned Surface Vessel (LUSV) program.

The LOSVs will each carry a 32-cell Mk41 Vertical Launch System (VLS) to supplement the firepower of the RAN’s manned warships. Its Lockheed Martin Aegis Baseline 9 combat system makes possible a Cooperative Engagement Capability (CEC) with Aegis-equipped manned surface ships and enables the vessel to carry out both Anti-Ballistic Missile (ABM) and conventional Anti-Air Warfare (AAW) operations.

If the LOSV program goes ahead, the ships will augment the RAN’s three Hobart-class AAW destroyers and six Hunter-class Anti-Submarine Warfare (ASW) frigates – which will still have a world-class AAW sensor and combat system combination – as well as the seven to eleven General-Purpose frigates to be acquired from later this year. None of these ships are over-endowed with Mk41 VLS launch cells: the Hobart-class ships have 48, the Hunter-class has 32 and the General-Purpose frigates will have just 16.

Importantly, the LOSV will be equipped with the Aegis Baseline 9 combat system: Aegis alone comes with the coveted CEC which the US Navy has only ever shared with Japan and Australia. All of the RAN’s Aegis-equipped warships are also being upgraded to Baseline 9 which enables ABM defence and protection of a sea or contiguous land area against hypersonic ballistic weapons.

So the LOSVs could operate in direct support of these ships – but they could also protect deployed Australian troops, Australian and allied ships threatened by hypersonic ballistic anti-ship missiles or even vulnerable Australian population centres.

The LOSVs obviously need to have an Aegis-equipped ship within communications range with a sensor suite that can detect conventional missiles, aircraft and ballistic missiles. The SPY-1D(V) radars on the Hobart-class can do this, and so can the CEAFAR2 radars on the Hunter-class.

We don’t know yet about the General-Purpose frigates, though most builders of the contenders at last year’s Indo pacific 2023 show in Sydney showed models of their ships with the CEAFAR2 radar and stated they used the Saab Australia 9LV Mk3E combat system/tactical interface which is used universally by the RAN.

The Mk41 VLS will enable anything from 128 quad-packed Evolved Sea Sparrow Missiles (ESSM) for self-defence, to 32 single-packed SM-2, SM-3, SM-6 or Tomahawk missiles for long-range anti-aircraft, anti-missile/ABM and strike purposes. As long ago as 2021 the US Navy conducted a successful CEC-enabled trial of Raytheon’s AMRAAM-based SM-6 aboard its Unmanned Surface Vessel (USV) Ranger using a Mk41 VLS as the launcher.

While an Australian-built autonomous LOSV may seem like a distant dream for most Australians, the reality is actually much firmer.

The US Navy and RAN have both proven the CEC works using the Aegis Baseline 8 system. Just as important, fully autonomous and optionally crewed vessels have been tested by both navies:  while the US Navy has had prototypes in the water for several years, Perth-based Austal Australia put an optionally crewed prototype to sea for the first time in March this year and finished the Sea Acceptance Trials (SAT) on this vessel in April.

The successful SATs (including Endurance Trials) of the remote and autonomously operated vessel Sentinel marked the first phase of what the RAN calls the Patrol Boat Autonomy Trial (PBAT). They consisted of a series of remote and autonomous navigation events conducted off the Western Australian coast during March and April 2024.

The trial vessel, the RAN’s de-commissioned Armidale-class Patrol Boat (ACPB) HMAS Maitland, employed Perth-based start-up Greenroom Robotics’ Advanced Maritime Autonomy Software to navigate reliably. At 57 metres LOA, Sentinel is by far the largest vessel operated in Australia to be operated remotely and autonomously.

Funded (at an undisclosed level) by the Commonwealth of Australia, PBAT is a collaboration between Austal Australia, Greenroom Robotics, the Brisbane-based Trusted Autonomous Systems Defence Cooperative Research Centre (TAS DCRC, which receives its core funding from the Department of Defence) and the Royal Australian Navy’s Warfare Innovation Navy (WIN) Branch. Its aim is to use the former ACPB to provide a proof-of-concept demonstrator for optionally crewed or autonomous operations.

The release in 2020 of the RAN’s Robotic and Autonomous Systems – Artificial Intelligence (RAS-AI) 2040 Strategy was the trigger for the TAS DCRC and Austal to get together. They saw an opportunity to re-purpose the former HMAS Maitland to define and better understand existing autonomous technology and how it could meet RAN needs. The partners also saw an opportunity to explore whether an autonomous platform could deliver asymmetric warfighting advantage.

Austal took possession of the decommissioned HMAS Maitland in 2022 and modifications included changes to the ship’s navigation, communications, bilges, CCTV, and electrical systems.

The Sentinel has been fitted with two autonomy systems: firstly, GreenRoom Robotics’ software-based GreenRoom Advanced Maritime Autonomy (GAMA) system, which enables remotely operated or full autonomous missions while complying with the International Regulations for Preventing Collisions at Sea, COLREGs, without crew intervention.

Secondly, a platform autonomy system, developed by Austal and based on the company’s in-house MARINELINK control and monitoring system, which enables operation of the Sentinel’s mechanical and electrical systems without crew intervention.

A key aspect of the initial trial was the endurance component, designed to observe Sentinel’s behaviour in an extended endurance mode. During this trial she operated autonomously with minimal to no crew interaction.

When the ship returns to sea the PBAT trial will focus on a bunch of other goals, starting with simply progressing the concept of remote operations and the autonomous certification approach.

At a sub-system level, the partners need to investigate and understand the sustained operation of shipboard mechanical systems reliably without crew intervention, including adding redundancy to enable operations at sea for extended periods, something the US Navy has explored also (see below). They also need to understand better how fuel management, communication and navigation systems can be made autonomous, and how they will work.

Longer-term, the PBAT trial will generate data contributing to risk reduction for future RAN projects involving remote or autonomous vessels. Short-term, the RAN could potentially transfer lessons learned about remote and autonomous systems to its current fleet to optimise crew workload: remote and autonomous operation has the potential to reduce crew workload and increase operational safety by reducing human error.

Austal says it is open to expanding the PBAT program and actively investigating opportunities to both extend current autonomy and optional crewing systems and integrate new systems to increase Sentinel’s capability or that of any future trials vessel.

Any future phases will be assessed to ensure the needs of the RAN’s Robotics and Autonomous Systems-Artificial Intelligence (RAS-AI) 2040 Strategy are still being met, the company says. Extension of this program will help to build the capabilities necessary to support two key requirements, says the company: the future LOSV program (which is where we came in); and the introduction of new technologies into the broader surface fleet to ensure future crewing requirements can be achieved. These aren’t stated as yet but the firm trend in Australia is to use fewer personnel and have smaller ship’s companies.

The PBAT program wasn’t established specifically with the LOSV program in mind, points out Austal, though everything to do with LOSV will benefit from the PBAT trial. Austal strongly supports the introduction of the LOSV to the Navy’s surface fleet, as you’d expect given that it will build the ships; and it points out also that its investment in autonomy, both in Australia and in the USA, has been with this type of platform in mind.

Austal’s Chief Executive Officer Paddy Gregg said the completion of the initial phase of the sea trials marks a significant PBAT milestone, successfully demonstrating the capability of the locally developed autonomous systems and their integration within a full-size, Australian-made naval vessel.

“Looking ahead, we are excited about the potential opportunities to work with [the RAN] to further advance the autonomous technology demonstrated during the trial; on projects such as the Large Optionally Crewed Surface Vessels (LOSV), recently announced by the Australian Government as part of the Surface Combatant Fleet Review,” Mr Gregg said in a statement.

So, this work positions the RAN to adopt autonomous technology in the future. In recent announcements Australian Defence Minister Richard Marles has said the planned LOSV platform will likely be acquired through formal RAN engagement with the US Navy’s LUSV program. Essentially, whatever the US Navy gets Australia will get, he’s suggesting, and the RAN will be a ‘fast follower’.

But however enticing the LUSV program looks, the PBAT trial is also designed to address Australia’s own sovereign requirement for a trusted autonomous system, especially an armed one. It needs to ensure the autonomous control system aboard the LOSV conforms with Australia’s needs and with the country’s high ethical standards for robotic and autonomous systems.

LUSV Program

The US Navy’s Large Unmanned Surface Vessel (LUSV) program is, as you’d expect, very similar to the RAN’s LOSV program. It is designed to deliver adjunct missile magazine capacity – essentially Mk41 VLS cells – to the Fleet as part of the US Navy’s Distributed Maritime Operations (DMO) concept. The difference is that the US Navy has been experimenting and developing technology in this area for several years and (budgets permitting) plans to order its first production autonomous ship as early as FY2025 at a planned cost of about US$315 million.

The US Navy’s vision for LUSV is for a ship between 200 and 300ft LOA with a full-load displacement of approximately 1,500 tons. It is intended to be a low-cost, high endurance, modular USV that can carry a variety of payloads.

Late last year US Naval Sea Systems Command issued a Request for Information (RFI), asking industry for feedback on its draft LUSV proposals. “[It] will be built to commercial American Bureau of Shipping (ABS) vice military standards,” said the RFI which closed in December. “As an adjunct magazine, LUSV will operate with Carrier Strike Groups (CSG), Expeditionary Strike Groups (ESG), Surface Action Groups (SAG), and individual manned combatants.”

“The LUSV will be capable of autonomous navigation, transit planning, and COLREGS compliant maneuvering and will be designed with automated propulsion, electrical generation, and support systems,” according to the US Navy’s FY 2024 budget documents.
“LUSV missions will be conducted with operators in-the-loop (with continuous or near-continuous observation or control) or on-the-loop (autonomous operation that prompts operator action/intervention from sensory input or autonomous behaviors).”

The Navy plans to issue its formal requirement for a production LUSV this calendar year. The PEO Unmanned and Small Combatants and PMS 406 are leading the US Navy’s effort.

The LUSV program started to gain traction in 2020 when the service awarded LUSV study contracts worth US$42 million to six US companies: Austal USA; Bollinger Shipyards; Fincantieri Marinette; Gibbs & Cox; Huntington Ingalls Industries (HII); and Lockheed Martin.

In March this year the US Navy announced that propulsion plants for solutions expected to be offered by four of the six – Bollinger, Fincantieri Marinette, HII and Gibbs & Cox – had all passed the mandated 720-hour engine reliability tests. These were intended to demonstrate that different propulsion plants can operate for extended periods without human intervention. This test is the milestone the LUSV program must pass before it can go into a formal development phase.

Meanwhile, autonomous ships already operated by the Navy have surpassed or come close to the 720-hour benchmark. A fleet of four unmanned prototypes – Unmanned Surface Vessels (USV) Mariner, Ranger, Seahawk and Sea Hunter – from the US Navy’s San Diego-based Unmanned Surface Vessel Division One (USVDIV-1) self-deployed across the Pacific to Sydney late last year to participate in the Australian Defence Force’s (ADF) EX Autonomous Warrior in October-November 2023. Later, they headed on to Japan before returning home.

The role of Austal USA is interesting. It is based in Mobile, AL, but is a subsidiary of Austal Australia. Last year the parent company signed the Heads of Agreement with the Australian government which could result in Austal becoming the government’s strategic shipbuilder at its Henderson base near Perth under a new Strategic Shipbuilding Agreement.

So, any ships built in Western Australia for the RAN would be built by Austal, including the LOSVs and between four and eight General-Purpose Frigates announced in this year’s Australian Surface Combatant Review.

Austal has been positioning itself carefully for the new world of autonomy. A year ago the company handed over to the US Navy an optionally crewed Expeditionary Fast Transport, USNS Apalachicola (EPF-13), the largest ship in the US fleet with autonomous capability. And in January, with L3Harris, it launched the OUSV-3 Vanguard, the first autonomous ship designed for the US Navy from the keel up, though sister to two existing USVDIV 1 ships, Ranger and Mariner.

There are no suggestions that Austal’s participation in the RAN’s PBAT trial will have any effect on its likely bid to build the LUSV for the US Navy, but its investment in research across two nations in autonomy and robotics won’t do it any harm at all.

Gregor Ferguson is a defence and innovation analyst, consultant and teacher as well as a defence innovation communicator and writer. He’s the Publisher and Editor of EX2, the online newsletter devoted to defence innovation. He is also the part-time Innovation Coordinator at the AMDA Foundation Limited which organises the Avalon Air Show, the Indo-Pacific International Maritime Exposition, the Land Forces Exposition and the Indian Ocean Defence & Security conference.

Gregor spent 14 years as Editor and then Editor-at-Large of Australian Defence Magazine (ADM), Australia’s leading defence industry journal. At the same time he became a regular contributor to The Australian, The Australian Financial Review and was the Australian correspondent for Defense News in Washington DC.

Credit Photo: The photo of the Endurance is credited to Austal.