Royal Navy: Huge "exciting" new submarine XV Excalibur that can sail by itself unveiled at glorious ceremony

XV Excalibur is the largest un-crewed underwater vessel trialled by the force to date and will be expected to protect British waters from the deeps below. Extensive sea trials are planned for the next two years.

Commodore Marcus Rose, deputy director Underwater Battlespace Capability, said: “The naming of Excalibur is a significant milestone for the Royal Navy and the upcoming sea trials will allow us to rapidly develop our understanding of operating un-crewed vessels of this size underwater.

“The lessons learnt from this exciting programme will build on our experience from existing programmes, such as the Mine Hunting Capability programme, to inform more extensive use of these technologies in a mixed force of crewed and un-crewed systems. Successful delivery of this programme is testament to what can be achieved in collaboration with our industrial partners.”

XV Excalibur was formally unveiled and named at HMNB Devonport, Plymouth, in front of 200 esteemed guests. VIPs including Rear Admiral James Parkin, Navy Director Develop, representatives from AUKUS nations, and trainees from across the navy and Cadets, were all in attendance.

It’s hoped the trials will contribute the Royal Navy’s understanding of the challenges that come with operating autonomous vessels of this size. The aim is for such vessels to deploy alongside crewed warships to deter various threats and conduct security operations.

This would include protecting critical undersea cables, tracking opposition submarines and intelligence gathering operations. The crewless craft was built by Plymouth-based MSubs, who specialise in automated submersibles.

Officially classified as an Extra-Large Uncrewed Underwater Vessel or XLUUV, Excalibur will join the recently created Fleet Experimentation Squadron. Sitting under the Disruptive Capabilities and Technologies Office, it will join surface ship XV Patrick Blackett which already sits within the squadron.

It will serve as the testbed for leading-edge maritime technology, both exploiting the natural Intelligence Surveillance and Reconnaissance (ISR) and stealth aspects of the XLUUV, alongside its ability to carry bespoke payloads. As a demonstrator, the vessel will not perform operational duties but will shape future concepts.

Since being delivered to the Royal Navy earlier this year, Excalibur – named after the Arthurian legend - and an experimental high-speed submarine trialled by the Royal Navy in the 1950s and ’60s – has undergone Harbour and Sea Acceptance Trials (HATs and SATs) in Devonport Naval Base.

Rear Admiral Parkin added: “This is an exciting day for the Royal Navy, the UK Armed Forces, and my team in particular as today marks the moment at which we take ownership of this superb vessel for the first time.

“In our journey towards autonomy and mass, it is vital we learn by doing, and Excalibur will be our mechanism for understanding the complexity and challenges of operating a future team of crewed and un-crewed vessel and systems underwater.”