Australia has reached another important milestone in its preparations for Submarine Rotational Force–West (SRF-West), with critical support elements now in place as work with AUKUS partners accelerates Australia’s ability to operate nuclear-powered submarines.
From next year, SRF-West will see AUKUS partners begin a rotational presence of UK and US conventionally armed, nuclear-powered submarines (SSNs) at HMAS Stirling in Western Australia.
This rotational presence aims to build Australia’s expertise and capability to support SSNs by increasing familiarity with UK and US SSNs. This is a necessary step to ensure Australia has the skills and systems needed to safely operate and sustain a fleet of SSNs operated by the Royal Australian Navy (RAN).
HMAS Stirling is undergoing an $8 billion expansion over the next decade to provide the scale of infrastructure required for both rotational SSNs during SRF-West and Australia’s future SSN fleet.
As part of this process, the US Navy has this week announced it will commence support activities at HMAS Stirling – in cooperation with Australia and the UK – with US personnel to begin rotating to HMAS Stirling later this year. This will include:
- The reestablishment of US Submarine Squadron 3 to oversee the operation of US nuclear-powered submarines (SSNs) rotating from HMAS Stirling in support of SRF‑West. Submarine Squadron 3 will work alongside and become increasingly integrated with Australian and UK personnel to lay the groundwork for Australia’s own maintenance, logistics, and operational support of our sovereign controlled and operated SSNs.
- The establishment of a Lead Maintenance Activity in WA from mid-2026 to support the maintenance of US submarines assigned to SRF-West, and provide ongoing valuable training to Australia’s workforce.
- The establishment of Naval Support Activity Stirling – which will grow in the coming months – to deliver support services and programs for US personnel, contractors, and their families rotating as part of SRF-West.
US force posture cooperation in Australia, including SRF-West, takes place under the Force Posture Agreement. This recognises that access and use of Australian facilities and areas is on a rotational basis, as mutually determined and at the invitation of Australia, with full respect for Australian sovereignty.
Defence and the Australian Submarine Agency will work with the US to ensure its personnel can seamlessly integrate into the WA community, minimising impact, including on housing, transport, and healthcare.
SRF-West will significantly develop Australia’s ability to operate, maintain and safely steward our future conventionally-armed, nuclear-powered submarines. Deploying our Navy personnel on visiting UK and US boats will provide valuable at-sea experience with naval nuclear propulsion. It will also strengthen the skills, systems and supply chains required to build and maintain Australian submarines.
This builds on work already underway in the US, where the Royal Australian Navy has more than 200 personnel on training and postings, focusing on the safe operation and qualification on nuclear-powered submarines.
In addition, more than 220 Australian industry personnel are now in the Pearl Harbor Naval Shipyard, building the experience needed to sustain Virginia class submarines. Since December 2025, more than ten of these industry workers have returned to Australia, and are applying their skills in Australia.
These announcements follow the recent AUKUS Defence Ministers’ Meeting held in Singapore on 30 May 2026 where Deputy Prime Minister Richard Marles, US Secretary of War Pete Hegseth, and UK Secretary of State for Defence John Healey announced the finalisation of necessary arrangements for the establishment of SRF-West from 2027. During their meeting, the ministers confirmed key SRF-West milestones continue to be met.