Royal Navy nuclear-powered submarine docks at HMAS Stirling

The Royal Navy’s nuclear-powered attack submarine HMS Anson has arrived at HMAS Stirling’s Fleet Base West for the first‑ever maintenance activity on a UK nuclear‑powered submarine in Australia. This marks a historic step in Australia’s readiness to operate and maintain conventionally‑armed, nuclear‑powered submarines.

Over the coming weeks, Australian personnel will work alongside partners from the United Kingdom (UK) and United States (US) on maintenance and familiarisation activities on the Astute-class submarine, says Defence in a media release. Around 100 personnel will contribute to the UK Submarine Maintenance Period (UK SMP) including members of the Royal Navy, the UK Submarine Delivery Agency, Royal Australian Navy, ASC Pty Ltd, and Pearl Harbor Naval Shipyard.

“This Submarine Maintenance Period is the latest demonstration of the continued momentum across all three partners to deliver AUKUS,” said Richard Marles, Deputy Prime Minister and Minister for Defence. “Australia, the UK and the US will work together over the coming weeks on the maintenance of HMS Anson – developing our skills, systems and infrastructure as we prepare for Submarine Rotational Force–West to begin next year.”

This builds on previous work completed on US Virginia-class submarines USS Vermont in 2025 and USS Hawaii in 2024, and strengthens the skills, systems and supply chains required for routine maintenance of nuclear‑powered submarines, says Defence.

“This is an important milestone that will build confidence in our strategic partners that we have the workforce able to deliver AUKUS submarines, and also lays ground for more jobs for locals,” said Pat Conroy, Minister for Defence Industry. “AUKUS partners are working together to achieve real operational benefits today, faster than we can working alone.”

Participation in the UK SMP represents another significant milestone in the lead up to the establishment of Submarine Rotational Force – West (SRF-W) at HMAS Stirlingfrom 2027 and will further build Australia’s familiarity with UK-designed submarines as the nation prepares to begin construction of SSN-AUKUS in Adelaide by the end of the decade, says Defence.

Two RAN officers have been embedded aboard HMS Anson, gaining invaluable operational experience on a conventionally-armed, nuclear‑powered submarine.

More than 50 Australians are now embedded within the UK Defence Nuclear Enterprise, says Defence, and the Royal Navy has provided offshore nuclear safety training to over 950 Australian Submarine Agency personnel.

The presence of HMS Anson also provides another opportunity to test and strengthen Australia’s nuclear stewardship systems, drawing on the world-leading safety practices of AUKUS partners.

During the HMS Anson visit, AUKUS partners will also undertake a combined AUKUS Pillar I and Pillar II activity, testing the interoperability of the Australian Speartooth Large Uncrewed Underwater Vehicle (LUUV) with the UK SSN, and assessing and enhancing AUKUS Pillar II anti-submarine warfare AI algorithms fitted to the RAAF P-8A Poseidon.