SSN-AUKUS

SSN-AUKUS is the trilateral nuclear-powered attack submarine design being developed under AUKUS Pillar 1 Phase 3. The submarine represents a new class of SSN that will serve both the Royal Navy (replacing the Astute-class) and the Royal Australian Navy (providing Australia's sovereign SSN capability after the Virginia-class interim period).

Key aspects of SSN-AUKUS:

1. Design basis: SSN-AUKUS is based on the UK's next-generation SSN(R) design, which succeeds the Astute-class. The UK leads the design effort through BAE Systems at Barrow-in-Furness, with Australian and US input on requirements and technology.

2. Nuclear propulsion: The submarine will use the Rolls-Royce PWR3 nuclear reactor, a new generation pressurized water reactor designed for the UK's Dreadnought-class SSBNs and adapted for SSN-AUKUS. The PWR3 represents a significant advancement in naval nuclear propulsion with improved efficiency, safety, and lifespan.

3. US technology contribution: The United States contributes technology and expertise to SSN-AUKUS, including combat systems, weapons, sensors, and potentially propulsion components. The US shares its extensive SSN experience (Virginia-class, Columbia-class) through the AUKUS framework.

4. Australian construction: After the UK builds the first SSN-AUKUS, subsequent boats will be built at Osborne Naval Shipyard in South Australia. This represents a massive industrial undertaking for Australia, requiring development of nuclear submarine construction capability from a relatively modest naval shipbuilding base.

5. Timeline:

• Late 2030s/early 2040s: First UK-built SSN-AUKUS enters service
• 2040s-2050s: Australian-built SSN-AUKUS boats enter service
• The program will serve into the 2070s and beyond

6. Industrial partnership:

• BAE Systems (UK) — prime contractor, submarine design and construction
• Rolls-Royce (UK) — nuclear reactor (PWR3)
• ASC (Australia) — Australian construction at Osborne
• US industry — combat systems, weapons, technology sharing

7. Capability: SSN-AUKUS will provide advanced SSN capability including:

• Stealth and quieting for anti-submarine warfare
• Advanced sensors including sonar and electronic support measures
• Weapons including torpedoes, cruise missiles (potentially Tomahawk), and mines
• Special forces delivery capability
• Intelligence collection
• Long-endurance nuclear propulsion for sustained operations throughout the Indo-Pacific

The SSN-AUKUS program represents a generational investment in both UK and Australian submarine capability. For Australia, it represents the development of an entirely new industrial capability—nuclear submarine construction—that will require decades of investment in workforce, infrastructure, and regulatory frameworks.

The program connects to the broader AUKUS framework through its trilateral design and construction approach. The US technology contribution ensures interoperability with US systems and leverages decades of US SSN experience. The UK design leadership builds on the UK's extensive SSN experience (Trafalgar, Astute, Dreadnought classes).

SSN-AUKUS also connects to the Australian Naval Nuclear Power Safety Bill and the regulatory framework being established for nuclear submarine operations in Australia. ANSTO will play a key role in nuclear stewardship for the Australian SSN-AUKUS fleet.