UK fires torpedo from an undersea drone for the first time
Key Points
- UK and US fired a heavyweight torpedo from the 12-metre undersea drone Excalibur in UK waters last week
- First launch of a torpedo from an uncrewed vessel by either country
- Test carried out under the AUKUS programme with a torpedo developed by the US and Australia
- New UK-US AI and Autonomy partnership announced to protect critical infrastructure
- MoD Rapid AI Delivery Taskforce to work with the US Department of War's AI office
The UK and US have fired a heavyweight torpedo from a 12-metre Plymouth-built undersea drone named Excalibur, the first time either country has launched one from an uncrewed vessel rather than a crewed submarine.
The Prime Minister’s Office announced the test on Tuesday (22 September) as Andy Burnham travelled to New York for the UN General Assembly and his first meeting with Donald Trump.
The firing took place in UK waters last week under the AUKUS programme, the three-way partnership between the UK, US and Australia that covers a new fleet of attack submarines and undersea autonomous systems.
The torpedo, which the US and Australia developed together, is designed to sink ships and deep-diving submarines. The government said the test marks a major advance in submarine technology for all three countries and a significant breakthrough for NATO’s undersea advantage.
Excalibur is an extra-large uncrewed underwater vehicle built by MSubs in Plymouth, and the Royal Navy took delivery of it in 2025 to trial how autonomous submarines could operate alongside crewed boats.
New AI and autonomy partnership
Alongside the test, Burnham announced the launch of a new AI and Autonomy partnership between the UK and US aimed at protecting critical national infrastructure, from sea lanes to airspace.
The work will pair the Ministry of Defence’s Rapid AI Delivery Taskforce with the Chief Digital and Artificial Intelligence Office at the US Department of War. The two bodies will focus on delivering trusted, interoperable AI and autonomy capabilities that strengthen deterrence and both countries’ technological edge.
“Our work together already shows what can be achieved when our two countries combine our expertise and innovation,” said Andy Burnham, Prime Minister.
“That ambition is underlined in our new defence partnership with the United States on AI and autonomy, bringing together the brightest minds to strengthen the protection of critical infrastructure, deter those who threaten our security, and use the enormous potential of AI to our advantage,” he added.
Burnham’s speech to the UN General Assembly on Tuesday evening is expected to centre on AI, making the case for international cooperation to harness the technology for good.
The government said the partnership builds on the technology already in development through AUKUS, and that the two countries intend to go further on next-generation collaboration.
