Submarine Rotational Force-West (SRF-West)

SRF-West (Submarine Rotational Force-West) is the initial phase of AUKUS Pillar 1, providing near-term enhancement of allied submarine capability in the Indo-Pacific while Australia develops its own sovereign SSN capability. Beginning around the end of 2027, UK and US nuclear-powered attack submarines will rotate through HMAS Stirling on Garden Island, Western Australia.

Key aspects of SRF-West:

1. Force composition: The SRF-West will include one UK Astute-class SSN and up to four US Virginia-class SSNs at any given time. The submarines will rotate on a regular basis, with each boat deploying for a period before returning to its home port.

2. HMAS Stirling infrastructure: Australia has committed AUD 8 billion for HMAS Stirling infrastructure upgrades to support SRF-West. This includes:

• Wharf facilities capable of berthing nuclear submarines
• Maintenance and repair infrastructure
• Crew accommodation and training facilities
• Nuclear safety and radiological protection systems
• Security infrastructure
• Fuel and supplies handling

3. Operational benefits:

• Provides immediate enhancement of allied submarine presence in the Indo-Pacific
• Allows Australian personnel to gain experience with nuclear submarine operations
• Creates a forward operating base for allied SSNs in a strategically critical location
• Demonstrates allied commitment to Indo-Pacific security
• Supports intelligence collection and surveillance operations in the region

4. Strategic context:

• SRF-West addresses the capability gap between the retirement of Australia's Collins-class submarines and the delivery of Virginia-class and SSN-AUKUS submarines.
• The Western Australian location provides access to the Indian Ocean and key strategic waterways including the Sunda and Lombok Straits.
• The increased allied submarine presence contributes to deterrence in the Indo-Pacific.

5. Nuclear regulatory framework:

• The Australian Naval Nuclear Power Safety Bill establishes the regulatory framework for nuclear submarine operations in Australian waters.
• US and UK nuclear submarines operate under their own national nuclear regulatory frameworks while in Australian waters, with bilateral agreements governing safety and liability.
• ANSTO provides nuclear stewardship expertise and support.

6. Political considerations:

• SRF-West has been subject to political debate in Australia, with some concerns about the presence of nuclear submarines in Western Australia.
• The Western Australian state government has engaged with the Commonwealth on safety, environmental, and economic aspects of the program.
• The economic benefits of HMAS Stirling expansion include jobs, local industry development, and technology transfer.

SRF-West represents a significant step in the AUKUS partnership, providing tangible near-term capability enhancement while Australia builds toward sovereign SSN capability. The program transforms HMAS Stirling from a conventional submarine base into a nuclear submarine-capable facility, establishing the infrastructure and expertise that will later support Australia's own Virginia-class and SSN-AUKUS submarines.