Helsing, Europe’s best-funded defence tech startup, has unveiled its latest product — an autonomous mini-submarine for underwater reconnaissance. 

Dubbed SG-1 Fathom, the sub is the latest addition to Europe’s growing fleet of ocean drones, which aim to better protect the continent’s ships and subsea infrastructure from surveillance, sabotage, and attacks. 

The 1.95-metre Fathom is designed to slowly patrol the ocean for up to three months at a time. The vessel is powered by an AI platform called Lura. The system is a large acoustic model (LAM) — like a large language model (LLM) but for sound. 

Lura is able to classify sounds made by ships and submarines and then pinpoint their locations. Helsing said the algorithm can identify sounds at volumes 10 times quieter than competing AI models. It also works at 40 times the speed of an equivalent human operator.

Helsing said the “mass-producible” submarines can be deployed in hundreds-strong “constellations” to carry out large-scale surveillance. 

Ocean reconnaissance of this kind has become increasingly urgent since the 2022 Nord Stream pipeline sabotage, which exposed the vulnerability of underwater assets to covert attacks. European nations NATO are also stepping up their maritime defences amid growing concerns over Russian aggression. 

In Ukraine, ocean drones have already become an important tool in its war against Moscow.

High-tech arsenal 

The war in Ukraine is increasingly characterised by battles between autonomous systems, mainly unmanned aerial vehicles (UAVs). However, the battle between machines is also playing out in the seas.  

Earlier this month, Ukraine used its Magura naval drone to shoot down two Russian aircraft. The Magura, armed with missiles, has been used extensively since 2023 to attack and destroy Russian ships and aircraft. 

The country is also expanding its fleet of waterborne drones. Last week, Ukrainian company Nordex unveiled the Seawolf, an uncrewed surface vessel (USV) for combat, surveillance, and border security applications.    

British company Kraken is developing a similar uncrewed boat that can engage enemies in combat or deliver cargo and personnel. Meanwhile, Denmark is set to trial autonomous sailboats to patrol the Baltic Sea looking for signs of potential threats.   

The adoption of drones at sea comes amid rising geopolitical tensions, which have prompted European officials to go all-in on defence tech. 

In March 2025, EU leaders endorsed the “ReArm Europe” plan, aiming to mobilise up to £683bn (€800bn) over the next four years to enhance military capabilities. Similarly, the UK government has committed to raising defence spending to 2.5% of GDP and wants to spend at least 10% of its defence budget on “innovative technologies”. 

Helsing looks to capitalise on this political momentum. The company told Bloomberg last month that it has “won over a dozen contracts” with “total order volumes of hundreds of millions of dollars” since its founding in 2021.  

Helsing, which is valued at €5bn ($5.4bn), is perhaps best known for its combat drones and AI software that acts like the brain for military vehicles such as fighter jets. Fathom marks its first entry into ocean-bound technology. 

Several naval forces have already shown interest in Helsing’s autonomous submarine, the company said. It aims to deploy the first fleets of underwater drones within a year. 

Defence tech is a key theme of the Assembly, the invite-only policy track of TNW Conference. The event takes place in Amsterdam on June 19 — a week before the NATO Summit arrives in the city.

Tickets for TNW Conference are now on sale — use the code TNWXMEDIA2025 at the checkout to get 30% off.