China's huge new unmanned submarine lies in wait for HMS Prince of Wales

Telegraph

29-04-2025

China appears to have developed an enormous robotic submarine. If so, China's rivals – Taiwan and the United States, among others – need to figure out what the sub is for. And fast. This year, Britain's Royal Navy will also be thinking hard about it, as its Carrier Strike Group has just set out on a voyage to the Indo-Pacific.
One possible mission might be among the most alarming. Large unmanned underwater vehicles are uniquely suited for covert minelaying: seeding shallow water with munitions that can break the keel of all but the largest warships.
In early February, China-watcher MT Anderson spotted in satellite imagery what appeared to be an approximately 150-foot submarine with cruciform fins and a very short sail. It could be a crewless design – a development of an even larger experimental UUV that appeared in China in 2018.
With just that satellite imagery to analyse, it's impossible to say for sure whether the new sub is unmanned and what it's for. But consider: among the many possible scenarios is a Chinese blockade of Taiwan.
Last year, the Center for Strategic and International Studies in Washington DC concluded that a blockade by the People's Liberation Army is actually the likeliest Chinese strategy for coercing Taiwan. 'This scenario aligns most closely with PLA doctrinal writings,' CSIS pointed out.
Underwater minefields, carefully positioned to strangle trade to and from Taiwan, could thread an important strategic needle: weakening Taiwan without provoking US intervention, CSIS pointed out.
'Mines serve to deter vessels from attempting to run the blockade, and they offer a more passive means for the PLA to threaten noncompliant ships,' CSIS explained. 'Without mines, China's forces will need to play a more active role in stopping entry into Taiwan and may therefore be put in more situations in which commanders have to make decisions about exactly how to engage.'
An announced military exercise would provide cover for the minelaying. 'During the exercises, PLA submarines covertly lay sea mines at the entrances of Taiwan's major ports,' the think-tank posited. 'The mines are timed to activate later to coincide with the start of blockade operations.'
The problem, of course, is how to emplace those mines without the Taiwanese military noticing. The waters around Taiwan are shallow. And Taiwanese and allied intelligence carefully track the comings and goings of the PLA Navy's manned submarines. 'Covert minelaying can be difficult,' according to CSIS.
Unmanned submarines, which could spend weeks or even months slowly trawling the China Seas, may stand a better chance of evading detection. Note that the US Navy plans to assign its own large UUV, the 84-foot Orca, to minelaying duties.
Deploying the $50-million robotic subs to lay mines not only answers a fleet requirement, Orca program manager Capt. Matt Lewis told The War Zone, it also avoids asking too much of an immature technology. Dropping a mine from the UUV is 'probably most akin to opening a door and having a payload drop out of it, slide out of it, fall out of it,' Lewis said.
If the Chinese UUV is also immature – and there's no reason to believe it isn't – it too could perform minelaying missions not just to meet an urgent requirement, but also to make good use of a new technology that's not yet capable of more complex tasks.
In that case, it's worth asking: what might the Chinese UUV do next? 'My perception of doing work like this is, we're at the initial stages … similar to aviation back in the early 20th century,' Lewis said of the Orca. 'I think we're at the early stages of figuring all that out. So, tremendous opportunity with Orca to go learn and expand what we can do and provide other new capabilities for the Navy.'