UK representatives from the Royal Navy, government, and industry observed the demonstration at Naval Submarine Base New London in Groton, Connecticut, in November 2025. The event featured U.S. Navy sailors from the Los Angeles-class fast-attack submarine USS Hartford operating the system using a shore-based Submarine Multi-Mission Team Trainer.
The demonstration supports plans to integrate AN/BYG-1 into the future SSN-AUKUS submarines, which will be designed by the United Kingdom and built and operated by the Royal Navy and the Royal Australian Navy. The U.S. Navy said incorporating the system into the baseline design underscores the interoperability of the three nations’ attack submarine fleets.
“We are extremely grateful to the crew of USS Hartford and the U.S. Naval Submarine School, who provided us with a fantastic demonstration of submarine warfighting that gives the UK a greater understanding of the AN/BYG-1 system,” said Cmdr. Rob Richards, RN. “This is an important milestone for the Royal Navy and demonstrates the significant progress made in submarine combat system capability collaboration across all of the AUKUS partner nations.”
“The great thing about systems like BYG-1 is that once you’re trained and proficient, you can go to any submarine in the Navy and be familiar with your station and the system you are operating,” said Lt. Scott Buckman from the Modernization Training Team. “Ultimately, with three nations operating variations of the system, we could see personnel from the three nations serving on each other’s boats, greatly enhancing interoperability, training, and ultimately improving our collective warfighting capabilities.”
The U.S. Navy said Australia’s acquisition and operation of nuclear-powered attack submarines under AUKUS Pillar I directly supports U.S. and allied efforts to maintain a favorable balance of power in the Western Pacific. The AUKUS Integration and Acquisition program office within the Department of the Navy is responsible for executing the partnership, with a focus on interoperability, sustainment infrastructure, and the highest standards of nuclear stewardship and nonproliferation.
