XV Excalibur
Royal Navy 12 m experimental extra-large uncrewed underwater vessel (XLUUV) built by MSubs under Project Cetus; in September 2026 it launched an exercise US Mk 48 heavyweight torpedo in an AUKUS trial.
Prototype
Products1
Newest unveiled first. Open a product for its milestone timeline, components and sources.
Sources6
Profile3
- 1
The Defense Post · Mar 7, 2025 · Supports Organization · description
“MSubs received the contract to build the first Cetus vessel in December 2022”
- 2Regulatory filingM SUBS LIMITED
Companies House · Supports Organization · legal name
“M SUBS LIMITED Company number 05874602”
- 3
MSubs · Supports Organization · description, Organization · hq city
“Whether you’d like to discuss a manned or unmanned underwater vehicle, specialist engineering services, operational support or a potential partnership”
Products3
- 4
Royal Navy · Sep 30, 2026 · Supports System
“XV Excalibur, an Extra-Large Uncrewed Underwater Vessel or XLUUV, was adapted with a specialist management system to successfully fire and control US Navy Mk48 Mod 4 Heavyweight Torpedo”
- 5Government recordU.S. Navy and Royal Navy Successfully Test Fire Torpedo from Unmanned Undersea Vehicle
U.S. Navy · Sep 22, 2026 · Supports System
“from an allied uncrewed platform, the Royal Navy's XV EXCALIBUR”
- 6Government recordRoyal Navy unveil 12 metre uncrewed submarine named after Excalibur
Royal Navy · May 15, 2025 · Supports Organization, System, System · maturity
“The crewless craft was built by Plymouth-based MSubs, who specialise in automated submersibles.”
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