China's undersea network: Beijing to unveil giant drone submarines in September; aims to challenge US Pacific surveillance

China is preparing to unveil two extra-large uncrewed underwater vehicles (XLUUVs) in September, weapons that could one day challenge US surveillance systems in the Pacific.

The drones will debut at a September 3 parade marking the 80th anniversary of the end of the Second Sino-Japanese War.

One model, the AJX002, is about 18–20 meters long and features pump-jet propulsion and modular transport capabilities. It has already been seen uncovered during rehearsals. A larger design has been kept under tarpaulin, but its dual stern masts and X-form rudders suggest a different concept, Asia News reported, citing Naval News.

Beijing's ministry of national defense said the parade will present “improved weapons, equipment.” At least six XLUUVs have been observed in practice runs.

Analysts believe the drones are designed to strike the US-led Fish Hook Undersea Defense Line , which tracks Chinese submarines as they move into the Pacific. Desmond Ball and Richard Tanter described the line in their book The Tools of Owatatsumi as stretching from Kyushu through Okinawa, Taiwan and the Philippines to Indonesia and the Andamans, with key nodes at Okinawa and Guam.

Ryan Martinson wrote in June 2025 that Chinese submarines face a “fairly high probability” of detection even inside the First Island Chain, since US seabed sensors, satellites, aircraft and unmanned vehicles can track them from port to patrol.

To counter this, David Axe reported in The Strategist that China is developing cable-cutting vehicles, explosive-planting submarines and long-range underwater drones triggered by acoustic signals—tactics designed to blind sensor arrays and delay repairs.

Neutralising the Fish Hook would also support Beijing’s Taiwan strategy . A 2024 Center for Strategic and International Studies report said PLAN submarines could blockade the island through covert mine-laying, disrupting shipping and supporting strikes. It would also strengthen China’s nuclear deterrent, which is now constrained by the JL-2 missile’s limited range. XLUUVs could help pave the way for broader patrols once the longer-ranged JL-3 is fully deployed.

The Pentagon’s 2024 China Military Power Report put China’s submarine fleet at 60, backed by an industrial base larger than America’s. The International Institute for Strategic Studies noted in its 2024 Asia-Pacific Regional Security Assessment that despite expanded allied patrols, gaps in anti-submarine warfare and domain awareness remain.