Military

Royal Navy robotic sub controlled from 10,000 miles away

Royal Navy robotic sub controlled from 10,000 miles away
XV-Excalibur meeting the public in May 2025
XV-Excalibur meeting the public in May 2025
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XV-Excalibur meeting the public in May 2025
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XV-Excalibur meeting the public in May 2025
XV-Excalibur surfacing
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XV-Excalibur surfacing
Deploying equipment for underwater test
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Deploying equipment for underwater test
View from EV-Excalibur
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View from EV-Excalibur
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The prototype Royal Navy robotic submarine XV-Excalibur has provided a glimpse of the fleet of the future by patrolling the waters at HMNB Devonport in Plymouth, England while controlled from a command center in Australia 10,000 miles (16,000 km) away.

Part of Project Cetus and built by Plymouth-based MSubs, the Extra-Large Uncrewed Underwater Vessel (XLUUV) XV-Excalibur was unveiled in May as a demonstrator platform to explore how best to use large robotic submarines to augment the Navy's fleet of nuclear attack boats. Under a two-year test program, Excalibur will study how such submarines can be employed in anti-submarine warfare, seabed warfare, and intelligence, surveillance, and reconnaissance.

By conventional submarine standards, Excalibur seems a tad small. In fact, it's about the size of the Navy's X-Craft midget submarines used during the Second World War, with a length of 39 ft (12 m), a beam of 7 ft (2 m), and a displacement of 19 tonnes – and speed, range, and propulsion system still on the classified list.

View from EV-Excalibur
View from EV-Excalibur

However, what it lacks in size, it makes up for in sophistication. Since it has no crew or the gear to support them, the interior can be packed to the gills with equipment, sensors, and payload modules to suit particular missions. The only key item it lacks is armament because of its testbed status, but it's still the most advanced uncrewed submarine in Europe.

The recent test under the auspices of the UK/US/Australia Maritime Big Play exercise was carried out in July 2025 as part of the biannual Exercise Talisman Sabre military exercises with 19 nations participating, including Australia, Canada, Fiji, France, Germany, India, Indonesia, Japan, the Netherlands, New Zealand, Norway, Papua New Guinea, the Philippines, the Republic of Korea, Singapore, Thailand, Tonga, the United Kingdom, and the United States, with Brunei and Malaysia attending as observers.

Aside from using Australia to demonstrate the ability to give commands to the autonomous submarine from half a world away, Project Cetus is part of the AUKUS Pillar II treaty, which shares submarine technology and other developments between the US, Britain, and Australia while aiding Australia in developing its own ability to build and operate its own nuclear AUKUS Class attack subs.

"This exercise demonstrates how we are exploiting the learning from our experimentation, by applying it to the Royal Navy’s growing arsenal of Uncrewed Underwater Vehicles; taking experimentation into the hands of the war fighter," said Captain Keith Taylor, RN, the UK Senior Responsible Owner for Maritime Big Play.

Source: Royal Navy

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6 comments
6 comments
yawood
Having an uncrewed submarine makes so much sense because it doesn't have to have any life support equipment (oxygen production, beds, food preparation, toilets etc etc)
anthony88
If AUKUS were only this, most Australians would be ok with it. AUKUS is AU$398 Billion for which we could get 12 diesel subs and still have AU$300 Billion left over to deploy 3000 (yes, three thousand at a $100million each) of these uncrewed subs.
Robt
@anthony88 That is not the case. Under AUKUS, Australia will buy nuclear powered Virginia class submarines from the US. What Australia does not have (by choice) is any current or future nuclear weapons capability.
JACKofALLTRADES47
These are the:1st. or :2nd. Generation; and being able to Keep track of the THUGS; is A top Priority) and they Do Not Need to Be ARMED) just Report back to A Base; that can ; send the appropriate response if necessary ) AND as HISTORY; has proven; competition will lower the price on future Unmanned Submarines; and EQUIPMENT) they have Hackers ; working for them Who are Looking πŸ‘€ for vulnerability in the system that would allow bad guys to override it)
johanschaller
@anthony88 Absolutely true. Australians by and large don't want money spent on the most expensive examples of military hardware, and given our extensive coastline, we need more things, not fewer, for every dollar spent. Under AUKUS, even if the US concedes that it's willing to sell us the Virginia subs, we'll be at the tail end of the order list, with the US Navy taking all the priority. If it was possible, it would be great to see us switch to the uncrewed subs such as described here, with a dozen conventional subs as previously ordered from France then reneged on. It would also avoid the need for Australia to have nuclear powered sub maintenance capability.
Brian M
Problem with unmanned sub's especially if its going to carry armaments (even more so if nuclear - UKI is that of security:
Hijacking by an opponent or terrorists, risk of communication/loss of mission controls issues and perhaps more worrying, the tempting danger to take the human being out of the urgent attack equation. For intelligence and non- armed patrols it makes a lot of sense, maybe even for non-nuclear weapons.