A Chinese Team Made A Big Splash With A Drone Swarm World Record

Researchers have set a record for the largest swarm of underwater drones in history. Officially recognized by Guinness World Records, the trial saw 116 TH-618 drones deployed in a 164 ft by 65 ft pool, where they autonomously executed a series of formations and maneuvers. (For comparison, and Olympic-sized swimming pool is approximately 164 ft by 82 ft.)

The August 2026 test has strong ties to the People’s Republic of China’s military pipeline. It was conducted by researchers at Northwestern Polytechnical University, an institution designated by the US government as a developer of technologies for the People’s Liberation Army (PLA). The university conducted the experiment in conjunction with Xi’an Tianhe Maritime Technologies, a subsidiary of defense contractor Xian Tianhe Defense Technology.

According to the South China Morning Post, the university said that developing submersible drone swarms “has always been a core challenge in the global field of underwater intelligent equipment. This time, the stable navigation of a cluster of hundreds of vehicles represents a breakthrough in the large-scale coordinated navigation of underwater unmanned systems.”

The record-setting day could prove a major milestone in the PLA’s development of autonomous drone swarms — an increasingly vital point of emphasis in the Eastern power’s military buildup. Currently the world’s largest navy, the PLA Navy (PLAN) is largely made up of smaller nimble ships designed to patrol the contested littoral waters of the South China Sea. And while the nation has commissioned three aircraft carriers in the last decade and a half, its fleet still lags behind the United States in total fire power. 

Some believe drones could close this gap and enable PLA’s increasingly expansive naval ambitions. Others worry the proliferation of drones will lower the threshold for naval engagements at a a time when naval intelligence is already beset with uncertainty.

The test’s TH-618 drones resemble long pipes equipped with four propellers and a camera. Roughly 2 ft long and half a foot wide, the 11lb drones have a range of just over 18 miles and can operate continuously for roughly 8 hours. To navigate, the drones use smartphone cameras attached to the front, allowing AI systems to adjust routes in real time to respond to underwater disturbances and collisions. According to the university, the drones can autonomously conduct complex maneuvers like terrain tracking, landmark recognition, vertical lift, depth and speed control and hovering in water using multi-degree-of freedom thrusters.

Underwater drone navigation is exceedingly complex when compared to its aerial counterpart because developers cannot utilize wireless communications or satellite positioning and navigation systems for course calibration. Low visibility and high water pressure further complicate subsurface coordination. Drones must rely on an amalgamation of underwater sensing, subsurface target detection and acoustic communication to autonomously respond to their irregular operating environment. Coordinating these efforts is another challenge altogether.

The culmination of over two decades of research, this record-breaking exercise could represent a major leap in AI-powered underwater navigation technologies. Over roughly 34 minutes, the drones relied solely on visual data to autonomously navigate around the pool, covering over 1,600 feet without human intervention. In creating a miniaturized submersible capable of coordinating autonomous responses to environmental stimuli, researchers at NWPU may have taken a step towards a new era of subsurface research, intelligence gathering and warfare.

Of course, these technologies have a long way to go before they revolutionize China’s naval operations. The controlled environment of a pool is a poor facsimile for proving the seaworthiness of autonomous submarine swarms. However, the test may indicate the direction of China’s subsurface and drone development programs.

China has leaned heavily into subsurface vessels and research. For the PLA Navy, the investment is dual-purpose, potentially boosting the country’s burgeoning mining and subsurface infrastructure efforts while enhancing its naval buildup and intelligence gathering. Both could have major geopolitical consequences given China’s expansive military and economic ambitions.

Subsurface drone swarms could prove a major boon for Beijing’s civilian and military naval operations. Researchers at Xi’an Tianhe Maritime Technologies highlighted the potential for coordinated swarms to monitor aquatic infrastructure and conduct research, such as inspecting gas pipelines or mapping the ocean floor. But this form of subsurface patrol could also lay the groundwork for submarine operations and defenses. 

In March 2026, researchers at CNN, the Pulitzer Center and environmental outlet Mongabay reported that China had spent years surveying the maritime environments of strategically critical waterways. Billed by Beijing as exploration missions for deep-sea mining and oceanographic research, the effort extended far beyond Beijing’s mining exploration rights and focused on key naval and economic shipping routes. Western military experts warned that the project likely boosted China’s subsurface intelligence operations. With critical deep-sea research projects on the rise, China is likely to continue its multi-faceted push.

For the PLAN, these swarms are likely only part of a seabed-to-space defense architecture known as the Transparent Ocean. In July 2026, two PLA-affiliated research institutions published a proposal for teams of drones to patrol the contested waters of the South China Sea. The robotic “fortress” would see China patrolling its geopolitical neighborhood with swarms of aerial, surface and submarine drones.

Already, the PLAN has made major strides towards these goals. China is the first country to develop full-size uncrewed submarines. Moreover, its reportedly developing at least two submersible motherships to launch uncrewed subs and drone carriers across its aerial, surface and subsurface fleet.

China isn’t alone in this pursuit. In the midst of the Russia-Ukraine war, in which a previously-inactive Ukrainian Navy downed one third of Russia’s fleet through hoards of aerial, surface and submarine drones, global powers are racing to add these asymmetric weapons to their fleets.

Drones present a unique opportunity for countries without traditional naval capabilities. Extremely cheap and easy to build, militaries are learning to overwhelm opponents with these disposable attack vehicles. Thwarting such assaults is difficult, especially when the defense missiles cost millions more than their targets. Moreover, AI-coordinated drone swarms are an acute threat to aircraft carriers.

In December 2025, Ukraine orchestrated the first successful subsurface drone strike against an enemy submarine, hitting a Russian submarine in Novorossiysk. The development forced Russia to begin deploying anti-drone nets across its submarine fleet. 

Traditional naval powers have made substantial progress towards deploying naval drones, too. Researchers from Poland, Germany, Portugal and Slovenia made strides towards launching autonomous subsurface drone swarms via the the European Defence Agency’s Swarm of Biomimetic Underwater Vehicles project. The U.S. military acknowledged the dangers drones pose to its nuclear submarine fleet when it initiated an open call for submarine drone defense systems in July 2026. A few months later, the US Navy launched its first unmanned surface vessel alongside a carrier strike group.

But China may have an advantage over its rivals. As the world’s leading manufacturer of both drone components and ships, its dual-purpose shipbuilding industrial complex is ideal for this type of military buildup. Unfortunately, the Trump administration won’t be able to tariff its way out of this arms race.