Mine countermeasures ‘mothership’ Stirling Citadel raised the white ensign on Jul. 25, transferring from the Royal Fleet Auxiliary. The ship is a step in the direction of a brand new method of countering sea mines, mirrored by different naval forces worldwide.
Procured in 2023 alongside RFA Proteus (K60), Stirling Citadel was beforehand often known as MV Island Crown. As Island Crown, the ship was lively in a assist and provide ship position for offshore power operations. For this position the 5,800 ton ship was outfitted with a big crane and dealing deck. To help with maneuverability, the bow of the ship homes two bow thrusters, and major propulsion is offered by two azipod models that may rotate and supply energy in any route. A 3rd azimuth thruster is mounted in the direction of the bow, retractable into the hull when not required.
All of those options lend themselves effectively to a brand new future working rising mine countermeasures (MCM) know-how, together with giant unmanned floor and undersea vessels. A extra complete overview of the ship’s design will be discovered from Navy Lookout.
In the present day is “Tremendous-lift-Saturday” as we strategy the pivotal second in upkeep of our @MacGregorGlobal offshore crane.
Working with our cluster assist workforce and @CammellLaird, our crane will probably be lifted, realigned and re-secured, prepared for future operations 🏗️ ⚓️ pic.twitter.com/06NzwUDFli
— HMS Stirling Citadel (@HMS_Str_Castle) April 27, 2024
Initially meant to be operated by the Royal Fleet Auxiliary as RFA Stirling Citadel, it was introduced in Might 2025 that the ship would as an alternative be transferred to the Royal Navy and commissioned as HMS Stirling Citadel. Formally, the reasoning for this switch was right down to the ship’s position being thought of a frontline tasking and extra inside the purview of navy crews, quite than the civilian crews of the RFA. Whereas that is definitely true to a point – and former mine countermeasures vessels (MCMVs) have been operated by the Royal Navy – a extra urgent want stems from a significant personnel disaster presently crippling the RFA.
In comparison with the Sandown and Hunt class MCMVs most just lately operated by the Royal Navy (only a handful of those stay lively), which each displaced at below 1,000 tons, Stirling Citadel is a a lot bigger vessel. This can be a reflection of quickly creating ways and applied sciences within the mine countermeasures area.
Reasonably than the vessel itself taking a direct position within the seek for and destruction of sea mines, it is going to as an alternative act as a hub for smaller, unmanned capabilities that will probably be deployed from and recovered by the ship. This technique of operation has seen some integration onto present MCMVs however the small dimension of the prevailing vessels locations huge limitations on the varieties of tools in a position to be carried.
Rising Applied sciences
The Royal Navy has invested in numerous new MCM applied sciences in recent times. These are largely targeted on uncrewed or optionally crewed floor vessels in addition to some undersea models.
Utilizing boats derived from the Sea class workboats now broadly employedd by the Royal Navy for coaching, assist, and inshore logistics duties, the ATLAS Distant Mixed Affect Minesweeping System (ARCIMS) is ready to be outfitted with numerous MCM payloads. Amenities can be found to function these as manned vessels if vital, in addition to remotely or utterly autonomously.
From the open transom, they’ll deploy current capabilities like towed sonar models, the Seacat UUV, and the SeaFox Mine Disposal System, in addition to new methods which can be below growth. By offloading these methods to uncrewed vessels, quite than working straight from the ship, the Navy can decrease the danger of crews being misplaced within the excessive threat position of sweeping for and destroying mines at sea. Utilizing a bigger vessel to assist these autonomous models additionally permits extra to be carried and operated concurrently, providing a extra complete and protracted functionality.
ARCIMS boats have already been deployed to the Persian Gulf, the place the Royal Navy has maintained a everlasting MCMV presence for a few years – although that is waning following the withdrawal of the Bay class assist ship and scaling down of the MCMV fleet. Additional trials on new methods have taken place nearer to dwelling, with the SWEEP MCM system having been accepted into service earlier this July.
An important milestone…
The #RoyalNavy is now in a position to deploy crewless minesweeping tools to hunt and destroy mines for the primary time.
Learn extra: pic.twitter.com/jv99ZJ1ybb
— Royal Navy (@RoyalNavy) July 4, 2025
Whereas Stirling Citadel and, sooner or later, new purpose-built MCM assist ships, will kind the first MCM functionality within the RN, it’s noteworthy too that many of those new methods can be deployed from the multi-purpose mission bays included on the Kind 26 and Kind 31 frigates. Together with the deliberate ahead basing of frigates, and the power for ARCIMS and related methods to be transported by strategic airlift plane, this is able to enable the Royal Navy to deploy a mine detection and clearance functionality to most areas of the world with only a few days of discover.
Whereas Stirling Citadel has retained, for now, its helicopter deck, it must be famous that this deck wouldn’t be appropriate for many varieties of navy helicopter. The format additionally doesn’t allow any form of hangarage for long run assist. If stored, although, it may very well be used to deploy aerial methods with an MCM functionality. Small rotary wing unmanned automobiles just like the Peregrine may very well be used as relay methods for working the autonomous floor/sub-surface vessels. Bigger platforms just like the Proteus with modular payloads may even accommodate MCM tools straight, although for long run operation one other ship would wish to offer shelter and technical amenities.
Airborne MCM is just not a brand new idea, although the RN has not beforehand adopted it at any vital scale. Within the U.S. the MH-60S Seahawk presents a restricted MCM functionality, whereas the large MH-53E Sea Dragon is devoted to the position with a big towed mine detection sled. The Sea Dragon is slated for retirement by 2027, with no direct alternative within the pipeline. Japan flies a variant of the AW101 Merlin within the MCM position, whereas South Korea is presently creating a devoted minehunting helicopter.
Abroad Developments
The UK is just not alone in shifting to a ‘mothership’ strategy for the MCM mission. Belgium and the Netherlands have partnered to obtain a purpose-built ship class of this kind, meant for working uncrewed MCM methods. They may substitute the Tripartite class of MCMVs, that are of an analogous configuration to the UK’s Hunt and Sandown courses.
Future Belgian Navy Metropolis-class mine countermeasures vessels BNS Oostende (M940) and BNS Tournai (M941) and future Royal Netherlands Navy Vlissingen-class mine countermeasures vessel HNLMS Vlissingen (M840) below building in Concarneau – November 28, 2024
SRC: TW-@pegge49 pic.twitter.com/B9mzrvlwC6
— WarshipCam (@WarshipCam) November 29, 2024
Throughout the Atlantic, the U.S. haven’t but procured a devoted alternative for its ageing Avenger class of MCMVs. Nevertheless, in essence, their meant alternative depends on MCM payloads that may be fitted on Independence class and Freedom class littoral fight ships (LCS). The issues with the LCS programme are well-known – whereas the MCM functionality marked its first deployment in March 2025, this functionality came to visit ten years delayed.
Whereas the shift in methodology is obvious, the extra conventional fashion of MCMV nonetheless stays viable in lots of circumstances. Surplus ships retired from Royal Navy service have discovered a house within the naval forces of Baltic nations, in addition to with Ukraine. Ukraine now has two Sandown class and three Tripartite class MCMVs crusing below its flag in Western Europe, awaiting a time the place they might safely switch to Ukrainian waters.
🇺🇦Ukrainian minehunters UNS Chernihiv, UNS Cherkasy, UNS Mariupol and UNS Melitopol alongside in Portland forward of mine warfare Train Sea Breeze 2025-2 (thirtieth June – eleventh July)
By way of @AytonJustyn pic.twitter.com/VV6SdWQ2U2
— Navy Lookout (@NavyLookout) June 29, 2025
With comparatively small crews and working prices, these MCMVs are helpful in sustaining a presence on the waters for these smaller nations with out many different naval vessels out there. Except for MCM missions, they’ll full coastal and offshore patrol duties, some survey work, and permit participation in worldwide workouts.
