Naval Systems

Thales MCM USV

Also known as
  • C-Sweep USV
  • MCM USV
  • MMCM USV
  • MMCM Primary System
  • PathMaster USV
  • Thales PathMaster
  • SLAM-F drone de surface
  • SLAM-F USV

Thales MCM USV is the 12 m uncrewed surface-vessel element of the Franco-British MMCM/SLAM-F mine-countermeasure system. The craft works from shore, a portable command center, or a mothership with payloads such as TSAM towed sonar, a remotely operated vehicle, and supporting command-and-control software, keeping operators outside the minefield while the system searches, classifies, and supports neutralisation of underwater threats. Public sources document prototype deliveries from 2021 and French and Royal Navy production deliveries from 2024 onward; this entry does not claim verified combat employment.

Thales MCM USV, Mine countermeasures uncrewed surface vessel, Naval Systems
Image source: Thales delivers first SLAM-F module to the French Navy - Naval News
Profile / Specs

Profile

Origin
France / United Kingdom
Built by
Thales
Type
Mine countermeasures uncrewed surface vessel
Service note
SLAM-F / MMCM program, 2021-present
Designer
Thales
Designed
2015-present
Produced
2024-present

Specifications

Length
12 m
Beam
4 m
Displacement
Up to 20.8 tonnes
Endurance
Up to 40 hours on mission
Speed
8 knots operating speed; 21 knots maximum speed
Mission
Stand-off mine detection, classification, identification, and neutralisation support
Sensors
Thales TSAM towed sonar and SAMDIS high-resolution multi-view sonar payloads are documented in public MMCM/SLAM-F reporting
Payloads
USV, TSAM towed sonar, remotely operated vehicle, lightweight operations centre, and secure command-and-control elements in the Royal Navy primary-system package
Control
Operated from a Portable Operation Centre, shore, or a mothership
System role
One of the USV elements in the SLAM-F/MMCM mine-countermeasure module
Operating conditions
Designed for uncrewed sonar survey and seabed mapping in complex environments, including sea state 4 in OCCAR and Royal Navy descriptions
Crew protection
Designed to keep sailors outside the mine-threat area during survey work
Program And System Context

The MMCM/SLAM-F craft is best understood as one surface node in a wider off-board mine-countermeasures architecture. OCCAR describes the program as a Franco-British effort to replace legacy mine-countermeasure methods with stand-off, remotely controlled systems that can work from shore facilities or motherships.

Program route

Lancaster House cooperation led to an OCCAR demonstration contract in 2015, prototype deliveries in 2021, and production deliveries to France and the United Kingdom from 2024 onward.

Mission package

Public UK and OCCAR descriptions place the USV alongside TSAM sonar, a remotely operated vehicle, a portable operations centre, and secure command-and-control software.

Service names

Public reporting names French deliveries including Canopus and Rigel, and Royal Navy craft including Ariadne, Adventure, and the Apollo demonstrator.

Variants

Public records identify national MMCM/SLAM-F deliveries mainly by navy and boat name rather than by a separate export model designation.

VariantConfigurationDesignation notes
French Navy SLAM-F surface droneFrench production SLAM-F USV

DGA delivered the first French mine-warfare surface drone to the Marine nationale on 19 December 2024; OCCAR and naval reporting identify Canopus as the first French production system and Rigel as a later French USV handover.

Sources: DGA first SLAM-F mine-warfare surface drone delivery, OCCAR Delivers First MMCM System to France, OCCAR Delivers a new Mine Warfare USV to France - Naval News

RNMB AriadneRoyal Navy first MMCM primary system

Royal Navy reporting identifies Ariadne as the first 12 m MMCM USV delivered to the service, with TSAM sonar, payload, and remote-command elements for evaluation before operational use.

Sources: New uncrewed boat to boost Royal Navy minehunting operations | Royal Navy

RNMB AdventureRoyal Navy second MMCM primary system

OCCAR identifies Adventure as the second UK MMCM primary system delivered in March 2026, following the first UK delivery in 2025.

Sources: OCCAR Delivers Second MMCM System to the United Kingdom

RNMB ApolloUK prototype and demonstrator

Royal Navy reporting names Apollo as a prototype MMCM vessel used in 2024 trials before Ariadne's production handover.

Sources: New uncrewed boat to boost Royal Navy minehunting operations | Royal Navy

Support Ships

Royal Navy reporting shows the MMCM USV moving between shore trials, transport ships, and a mine-hunting mothership as the service prepares the system for operational use.

CarrierCarrier typeCarriage evidence
HMS Stirling Castle, Mine countermeasures mothership, Naval SystemsHMS Stirling CastleMine-hunting support ship

Ariadne was loaded onto HMS Stirling Castle for transportation to Gibraltar before docking with RFA Lyme Bay during Royal Navy trials ahead of a potential Strait of Hormuz mine-clearance mission; USNI News separately identified Ariadne as part of Lyme Bay's embarked MMCM package.

Sources: Royal Navy crewless mine-hunting system docks in support ship for the first time ahead of potential Hormuz mission, U.K. Mine Countermeasures Mothership Leaves Gibraltar for Potential Strait of Hormuz Mission - USNI News

Timeline

Thales MCM USV Key Events

  1. OCCAR demonstration contract awarded

    OCCAR records the March 2015 award of the MMCM demonstration-phase contract after France and the United Kingdom initiated the bilateral mine-countermeasures program under the Lancaster House framework.

    Sources: MMCM - Maritime Mine Counter Measures | OCCAR

  2. Prototype systems delivered to France and the United Kingdom

    OCCAR announced delivery of two MMCM unmanned-system prototypes to the United Kingdom and France, describing the system as a Thales-procured package of surface and underwater vehicles supervised from a Portable Operation Center.

    Sources: OCCAR delivered two prototypes of the MMCM Unmanned System

  3. French Navy receives first uncrewed mine-warfare module

    OCCAR and DGA announced delivery of the first SLAM-F mine-warfare surface drone to the French Navy, with DGA listing the 12 m, 4 m USV and its towed sonar as the first step toward an operational surface-autonomous capability.

    Sources: OCCAR Delivers First MMCM System to France, DGA first SLAM-F mine-warfare surface drone delivery

  4. Royal Navy announces Ariadne delivery

    The Royal Navy said RNMB Ariadne, a 12 m uncrewed surface vessel with payload and remote-command elements, had been delivered for training and operational evaluation.

    Sources: New uncrewed boat to boost Royal Navy minehunting operations | Royal Navy

  5. French Navy receives another MMCM USV delivery

    Calibre Defence reported that Thales delivered an MMCM USV to the French Navy, following the first French delivery in December 2024 and the earlier Royal Navy handover in March 2025.

    Sources: Thales delivers MMCM USV to French Navy - Calibre Defence

  6. Second UK MMCM primary system delivered

    OCCAR announced delivery of Adventure, the second MMCM primary system for the United Kingdom and Royal Navy, following the first UK delivery in 2025.

    Sources: OCCAR Delivers Second MMCM System to the United Kingdom

  7. Ariadne docks with RFA Lyme Bay

    Royal Navy and USNI reporting described Ariadne docking with RFA Lyme Bay after Portland trials and transport by HMS Stirling Castle, a support-ship integration milestone ahead of a possible Strait of Hormuz mission.

    Sources: Royal Navy crewless mine-hunting system docks in support ship for the first time ahead of potential Hormuz mission, U.K. Mine Countermeasures Mothership Leaves Gibraltar for Potential Strait of Hormuz Mission - USNI News

Media

Thales MCM USV Videos

Thales MCM USV Images

Thales MCM USV, Mine countermeasures uncrewed surface vessel, Naval Systems - view 1
Source: Thales delivers first SLAM-F module to the French Navy - Naval News
Thales MCM USV, Mine countermeasures uncrewed surface vessel, Naval Systems - view 2
Source: Thales delivers first SLAM-F module to the French Navy - Naval News
Related Weapon Systems
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Sandown class, Single-role minehunter, Naval SystemsNaval SystemsSandown classSingle-role minehunterThe Sandown class is a British single-role minehunter family built by Vosper Thornycroft around a low-signature hull, Type 2093 sonar, remote mine-disposal vehicles, and light self-defense armament. Royal Navy and export ships have served in mine-countermeasures roles with the United Kingdom, Saudi Arabia, Estonia, Ukraine, and Romania; a 2025 House of Commons Library briefing described HMS Bangor as the last Sandown-class vessel in Royal Navy service. Direct conflict sourcing places HMS Sandown in NATO Adriatic ordnance clearance after Operation Allied Force and Sandown-class vessels in coalition route-clearance work around Umm Qasr during the 2003 Iraq War.
Ratel S, Uncrewed ground vehicle / remote-mining and explosive-delivery robot, Support EquipmentSupport EquipmentRatel SUncrewed ground vehicle / remote-mining and explosive-delivery robotRatel S is a Ukrainian uncrewed ground vehicle built for remote mining, explosive delivery, observation, and short-range ground attack missions. Developed in Ukraine's wartime robotics ecosystem and publicized through the Brave1 defense-tech cluster, it gives Ukrainian operators a small wheeled platform that can move an explosive or mine payload toward Russian positions while reducing direct exposure; Ukrainian reporting has tied it to bridge, position, and underground-passage attacks in Donetsk Oblast.
Livadiya-ME mine-hunting sonar, Shipborne mine-hunting sonar, Naval SystemsNaval SystemsLivadiya-ME mine-hunting sonarShipborne mine-hunting sonarLivadiya-ME is a Russian shipborne mine-hunting sonar system for detecting, classifying, and cueing action against moored, bottom, and near-bottom mines. Public product-reference material describes low- and high-frequency antenna elements, automated coordinate measurement, mine-countermeasures control-system cueing, and an antenna package carried by a remotely operated underwater vehicle. Open reporting ties the sonar to the Project 12700/12701 Alexandrit mine-countermeasures family, while Weapons.rf identifies Aquamarin as developer and Taganrog Plant Priboy as producer.
Hunt class, Mine countermeasures vessel class, Naval SystemsNaval SystemsHunt classMine countermeasures vessel classThe Hunt class is a British mine countermeasures vessel class built by Vosper Thornycroft and Yarrow Shipbuilders for low-signature minehunting, route clearance, and coastal patrol work. Royal Navy and Ministry of Defence sources document HMS Brocklesby clearing mined approaches in the Gulf, Iraq, and Libya, while the remaining Royal Navy ships use sonar, clearance divers, glass-reinforced plastic hulls, and SeaFox mine-disposal vehicles to find and neutralize mines.

Sources

DGA first SLAM-F mine-warfare surface drone deliveryPublisher: French Ministry of the Armed Forces / DGA | Note: Supports the 19 December 2024 French first-drone delivery, Thales Underwater Systems/OCCAR program context, 12 m length, 4 m beam, up to 20.8 t displacement, up to 40 h mission endurance, 8-knot operating speed, 21-knot maximum speed, and SAMDIS towed-sonar payload. | Accessed: 2026-07-01MMCM - Maritime Mine Counter Measures | OCCARPublisher: OCCAR | Note: Supports the Franco-British MMCM program background, stand-off command concept, 2015 demonstration contract, 2020 Stage II production contract, and shore or shipboard command-center framing. | Accessed: 2026-07-01OCCAR delivered two prototypes of the MMCM Unmanned SystemPublisher: OCCAR | Note: Supports the November 2021 prototype deliveries, the Thales procurement context, the USV and UUV system composition, and the Portable Operation Center control model. | Accessed: 2026-07-01OCCAR Delivers First MMCM System to FrancePublisher: OCCAR | Note: Supports the December 2024 first French MMCM system delivery, the readiness/training context for the French Navy, and uncrewed sonar survey operations in sea state 4. | Accessed: 2026-07-01New uncrewed boat to boost Royal Navy minehunting operations | Royal NavyPublisher: Royal Navy | Note: Supports the RNMB Ariadne delivery, 12 m length, TSAM payload, autonomous or remote-control options, portable command centre context, and planned Royal Navy operational evaluation. | Accessed: 2026-07-01OCCAR Delivers Second MMCM System to the United KingdomPublisher: OCCAR | Note: Supports the March 2026 delivery of Adventure as the second UK MMCM primary system, the expanded mission suite, Portable Operation Centre control, and ROV training capability. | Accessed: 2026-07-01UK to contribute drones jets and warship to Multinational Mission to secure the Strait of Hormuz - GOV.UKPublisher: UK Ministry of Defence | Note: Supports the UK defensive Hormuz mission-planning context, autonomous mine-hunting equipment contribution, and RFA Lyme Bay mothership upgrade context without confirming MMCM mine-clearance operations. | Accessed: 2026-07-01U.K. Mine Countermeasures Mothership Leaves Gibraltar for Potential Strait of Hormuz Mission - USNI NewsPublisher: USNI News | Note: Supports Ariadne's inclusion in the RFA Lyme Bay embarked MMCM package, the Stirling Castle transport link, the potential Strait of Hormuz mission context, and the absence of confirmed mission start at the time of reporting. | Accessed: 2026-07-01Royal Navy crewless mine-hunting system docks in support ship for the first time ahead of potential Hormuz missionPublisher: Royal Navy | Note: Supports the Ariadne support-ship integration milestone, its loading on HMS Stirling Castle, docking with RFA Lyme Bay, TSAM sonar use, Portable Operating Centre control, and the source-limited potential-Hormuz context without claiming verified conflict use. | Accessed: 2026-07-01OCCAR Delivers a new Mine Warfare USV to France - Naval NewsPublisher: Naval News | Note: Supports the Rigel handover, Canopus/Rigel French delivery sequence, French SLAM-F system composition, and Couach/Thales/L3Harris ASV production context. | Accessed: 2026-07-01Latest MMCM Milestones Paves the Way for Thales on International MCM Markets - Naval NewsPublisher: Naval News | Note: Supports the PathMaster product context, 2020 production-stage milestone, Royal Navy and Marine Nationale production package composition, Mi-Map context, and selected Naval News video metadata. | Accessed: 2026-07-01SLAMF Archives - Naval NewsPublisher: Naval News | Note: Supports selected Naval News video metadata for the 2024 SLAM-F French Navy overview video. | Accessed: 2026-07-01Thales delivers first SLAM-F module to the French Navy - Naval NewsPublisher: Naval News | Note: Supports the December 2024 French Navy delivery, the SLAM-F/MMCM program context, the two-USV/two-AUV module composition, and the primary gallery image provenance. | Accessed: 2026-07-01SLAMF programme: the future of French Navy's mine warfare capabilities - EDR MagazinePublisher: EDR Magazine | Note: Supports Thales leadership of the MMCM industrial effort, the Pathmaster name for the commercial system, the phased SLAM-F roadmap, and the program image provenance. | Accessed: 2026-07-01Thales delivers MMCM USV to French Navy - Calibre DefencePublisher: Calibre Defence | Note: Supports the November 2025 French Navy delivery, the first-of-its-kind MMCM USV framing, and the article image provenance. | Accessed: 2026-07-01Naval Drone with Next-Gen Sonar Delivered to French Navy for Mine Warfare & Countermeasures | USTPublisher: Unmanned Systems Technology | Note: Supports the 2025 delivery, the TSAM towed sonar and SAMDIS multi-view sonar fit, and the crew-exposure reduction context. | Accessed: 2026-07-01