The Belgian Navy’s lead next-generation minehunter vessel, M941 Tournai, has commenced sea trials in the North Sea. Designed under the Franco-Belgian rMCM (replacement Mine Counter Measures) program and built by Kership (a Naval Group and Piriou joint venture), Tournai is pioneering a fully drone-based approach to naval mine warfare. The milestone marks a significant shift in NATO-aligned navies’ adoption of unmanned systems for littoral and offshore mine countermeasure (MCM) operations.
City-Class Minehunters: A New Paradigm in Naval MCM
The Tournai is the first of twelve “City-class” mine countermeasure vessels being developed under the binational rMCM program launched by Belgium and the Netherlands. This €2 billion initiative aims to replace both navies’ aging Tripartite-class minehunters with a new generation of vessels that rely primarily on offboard unmanned systems rather than traditional hull-mounted sonar or mechanical sweeping gear.
The City-class ships are designed around a modular mission architecture that enables rapid deployment of various autonomous systems. Each vessel will operate a comprehensive suite of unmanned vehicles including:
- A18-M Autonomous Underwater Vehicle (AUV) – Developed by ECA Group for deep-sea mine detection using synthetic aperture sonar (SAS).
- Inspector 125 Unmanned Surface Vehicle (USV) – A multi-role platform capable of deploying and recovering other drones while conducting remote sonar scans.
- SEASCAN MK2 ROV and K-STER C expendable mine neutralizers – For identification and disposal of mines.
This approach allows operators to remain outside the threat envelope while conducting high-risk operations such as mine detection and neutralization. The ships themselves act more as motherships or command hubs than traditional sweepers.
M941 Tournai Sea Trials Begin in North Sea
The sea trials for Tournai, which began in late October 2025 off the French coast near Concarneau before progressing to Belgian waters, are focused on validating both platform performance and integration with its unmanned systems suite. These include propulsion performance tests, navigation system calibration, communications interoperability checks (including Link-22 readiness), and early-stage operational evaluations of its drone launch/recovery capabilities.
The trials are expected to last several months before formal delivery to the Belgian Navy in early 2026. According to Naval Group officials interviewed during Euronaval 2024 and subsequent updates from Belgium’s Ministry of Defence (MoD), full operational capability (FOC) is projected for late 2026 after extensive crew training and system validation.
Unmanned Systems Integration: ECA Group’s UMIS Toolbox
A key differentiator for the City-class program is its reliance on ECA Group’s “UMIS” toolbox — an integrated suite that combines multiple unmanned platforms into a unified command-and-control ecosystem. The UMIS architecture enables:
- Real-time data fusion from multiple sensors across air/surface/underwater domains.
- Autonomous mission planning based on threat libraries and environmental data.
- Semi-autonomous or remote-controlled deployment via secure satcom or line-of-sight links.
This level of integration reduces operator workload while increasing mission tempo — allowing simultaneous deployment of multiple drones across different sectors. The Inspector USV acts as both a communication relay node and a launch platform for AUVs/ROVs operating beyond line-of-sight from the mothership.
The system has been tested extensively at ECA’s test range in Toulon since mid-2023. Early feedback from Belgian Navy operators suggests high confidence in reliability but notes challenges in rough-sea drone recovery — an issue being addressed through software updates and mechanical refinements to launch/recovery cradles.
Bilateral Procurement Strategy & Industry Implications
The rMCM program represents one of Europe’s most ambitious naval procurement collaborations between NATO allies. Belgium serves as lead nation for procurement while the Netherlands leads on operational doctrine development. Both navies will receive six vessels each between 2026–2030 under current schedules.
Kership is responsible for shipbuilding at its Concarneau yard; meanwhile Thales provides onboard combat management systems including M-Cube CMS adapted for drone-centric operations. ECA Group supplies all unmanned components under a contract worth over €450 million signed in May 2019.
This project also supports European defense industrial consolidation goals under PESCO frameworks by promoting cross-border supply chains involving over 40 subcontractors across France, Belgium, Germany, and Italy.
NATO Implications & Future Export Potential
The successful deployment of City-class vessels could reshape NATO naval doctrine around expeditionary MCM operations. By removing crews from direct exposure zones — especially in contested littorals like the Baltic or Black Seas — these ships offer scalable risk mitigation options aligned with evolving hybrid threats such as seabed warfare or smart mines triggered by acoustic/magnetic signatures.
Several allied navies including Canada, Norway, Poland, and Greece have expressed interest in similar capabilities either through direct acquisition or technology transfer agreements. ECA Group has already offered export variants based on UMIS toolbox configurations adaptable to legacy platforms without requiring full ship replacement — an attractive option for budget-constrained fleets seeking incremental modernization paths.
Outlook: From Trials to Operational Readiness
If sea trials proceed without major delays or technical setbacks, M941 Tournai will become operationally available by Q4 2026. Its deployment will mark not just a technological milestone but also an operational shift toward distributed autonomous maritime operations within NATO task groups — particularly relevant amid growing tensions around strategic chokepoints like GIUK Gap or Eastern Mediterranean SLOCs threatened by irregular naval tactics such as mining campaigns or underwater sabotage.
Belgium’s commitment to this transformation positions it at the forefront of European naval innovation despite limited fleet size — offering lessons applicable far beyond Benelux waters as global navies recalibrate toward unmanned-first doctrines across blue-water and brown-water theaters alike.
