The Pentagon said Monday it picked the USS Colorado (SSN-788) to be the first U.S. Navy Virginia-class attack submarine assigned to Submarine Rotation Force West (SRF-West), marking the next step in the AUKUS submarine process, starting in late 2027.
SRF-West aims to help Australia prepare to ultimately operate, maintain and support its own nuclear-powered and conventionally-armed SSNs. Australia will start by hosting a rotational presence of up to four U.S. SSNs and one United Kingdom Astute-class attack submarine located at HMAS Stirling in Western Australia. This will expand the maintenance and sustainment infrastructure for AUKUS partners in the region.
“The selection of USS Colorado (SSN 788) as the first submarine assigned to SRF-West in 2027 marks a significant milestone for AUKUS Pillar I and is a decisive step in strengthening collective deterrence in the Pacific,” U.S. Secretary of Defense Pete Hegseth, Australian Defense Minister and Deputy Prime Minister Rochard Marles and U.K. Secretary of State for Defense West Streeting, said in a joint statement.
The deployment of the Colorado is the next early step under AUKUS Pillar I, leading into the U.S. selling three to five Virginia-class attack submarines to Australia in the 2030s. Later, Australia plans to ultimately build its own SSN-AUKUS boats in the 2040s while sharing a design with the U.K. Royal Navy.
This comes after the AUKUS defense ministers said in May that Australia’s 2030s submarine purchases would exclusively consist of used submarines rather than the previously planned mix of new and used boats.
The government officials said this comes ahead of an upcoming third U.S. submarine maintenance period later this week, when a U.S. Virginia-class submarine will perform maintenance at Stirling to further demonstrate the host country;s growing ability to sustain allied submarines.
Previously, in 2024 the USS Hawaii (SSN-776) underwent repair and maintenance with the crew of the submarine tender USS Emory S. Land (AS-39) and in 2025 the Vermont (SSN-792) traveled to Stirling for an availability with Australian maintenance workers without using the U.S. tender.
In February, the Royal Navy HMS Anson (S123) also arrived at HMAS Stirling for its own maintenance availability with Australian workers.
Rep. Joe Courtney (D-Conn.), ranking member of the House Armed Services seapower subcommittee and whose district represents prime submarine builder General Dynamics Electric Boat, welcomed the news and noted SSN-788 was built by Electric Boat.
“The activation of SRF-West puts Australia one step closer along the Optimal Pathway to Australia operating its own nuclear-powered submarine capability,” Courtney said in a statement. “The combination of U.S. and U.K. attack submarine rotations and Australian nuclear-powered submarines will transform allied naval posture in the Indo-Pacific. AUKUS Pillars I and II continue full steam ahead with Congress and the Navy in lock step with the UK and Australia.”
Exchange Monitor affiliate Defense Daily first published a version of this story.
