Netherlands transfers second Alkmaar-class minehunter Henichesk to Ukraine for Black Sea mine clearance.

The Netherlands is strengthening Ukraine’s ability to secure its coastline and critical sea lanes by transferring an Alkmaar-class mine countermeasure vessel after fully training its crew. Announced on April 16, 2026, by Ukrainian President Volodymyr Zelensky, the move directly enhances Ukraine’s capacity to detect and clear naval mines, a key requirement for protecting shipping routes, enabling amphibious operations, and sustaining economic lifelines in contested waters.

The Alkmaar-class vessel brings specialized mine-hunting sensors and neutralization systems designed to operate in high-risk littoral environments where mines threaten both military and civilian traffic. Its addition to Ukraine’s growing fleet reflects a broader push toward restoring maritime freedom of movement and building resilient naval capabilities focused on survivability, precision, and post-conflict recovery of sea access.

Related topic: Belgium donates last four Tripartite-class minehunters to Bulgaria to secure Black Sea naval routes

The Henichesk, hull number M314, is the former HNLMS Makkum (M857), a Royal Netherlands Navy Alkmaar-class minehunter that has undergone decommissioning, refit, and crew training prior to its delivery. (Picture source: Dutch MoD)

On April 16, 2026, Ukrainian President Volodymyr Zelenskyy confirmed that the Netherlands would transfer an Alkmaar-class minehunter to Ukraine, continuing a maritime assistance first announced in March 2023. The vessel, now named Henichesk (hull number M 314), is the former HNLMS Makkum (M857), laid down on 28 February 1983, launched in 1985, and commissioned on 13 May 1985. It remained in service until November 25, 2024, when it was decommissioned after nearly forty years of operations that included NATO exercises such as BALTOPS.

The ship underwent maintenance and reconfiguration prior to transfer, with part of its equipment replaced due to prior removal during decommissioning. Ukrainian crews were trained in the Netherlands over a period of roughly twelve to fifteen weeks, including simulator training and sea phases conducted from Zeebrugge and other locations. Training included navigation, mine warfare procedures, firefighting, and damage control, with support from Dutch, Belgian, and German personnel. The vessel, expected to enter Ukrainian service as early as June 2026 and take part in the Sea Breeze exercise in 2027, is the second Alkmaar class ship transferred by the Netherlands after Vlaardingen, renamed Melitopol, after their withdrawal from Dutch service. 

The Royal Netherlands Navy is replacing the Alkmaar-class with the Vlissingen-class, with deliveries scheduled between 2025 and 2030, leading to the phased decommissioning of legacy ships such as Makkum. After decommissioning, the vessel required refurbishment, including reinstallation of removed onboard systems and basic equipment, as some components had been redistributed within the Dutch fleet. Ukrainian personnel began training before the minehunter was fully transferred, initially using sister ships such as Vlaardingen and later transitioning to operational sea training. The training pipeline also included English-speaking instruction for crew members to ensure interoperability with NATO procedures.

Coordination involved multiple entities, including naval training centers, maintenance teams, and logistics units responsible for preparing the ship for transfer. The formal handover took place in 2025 following completion of these stages to ensure that the receiving crew could operate the vessel immediately upon commissioning under Ukrainian command. The Henichesk retains the original configuration of the Alkmaar-class, a Tripartite minehunter design developed jointly by the Netherlands, Belgium, and France in the 1970s. The vessel has a full load displacement between 543 and 588 tons, a length of 51.5 meters, a beam of 8.9 meters, and a draft between 2.6 and 3.8 meters depending on load.

Propulsion is provided by a Werkspoor A RUB 215 V12 diesel engine producing between 1,370 and 1,860 kilowatts, driving two propellers and supported by bow thrusters for maneuvering. Maximum speed is 15 knots, with an operational range of approximately 3,000 nautical miles at 12 knots. The crew consists of approximately 44 personnel, including specialists for mine warfare operations. The hull is constructed from fiberglass-reinforced polyester to minimize magnetic signature and reduce the risk of triggering magnetic mines. Armament is limited to a single 20 millimeter gun or heavy machine guns. The mine countermeasure systems onboard the Henichesk are centered on detection and neutralization rather than sweeping.

The primary sensor is the DUBM 21B sonar, capable of detecting and classifying objects at distances approaching one kilometer and at depths up to approximately 80 meters. The vessel carries two PAP 104 remotely operated vehicles, which are wire-guided and equipped with cameras to visually confirm targets. These vehicles can deliver explosive charges to destroy mines at a safe distance from the ship. Navigation is supported by a Racal Decca 1229 radar system, while onboard plotting systems assist in tracking and classifying contacts. In addition to ROV operations, divers can be deployed to place charges manually when required. The operational method involves systematic scanning of the seabed, identification of individual mines, and controlled neutralization.

This approach is slower than minesweeping but provides higher accuracy in complex environments with mixed or legacy minefields. The Ukrainian need for mine countermeasure vessels is driven by the scale and distribution of naval mines in the Black Sea since February 2022. Both Russian and Ukrainian forces have deployed mines in coastal and offshore areas, including moored contact mines and drifting mines that have detached from their anchors. Concentrations are highest in the northwestern Black Sea, particularly near Odesa and along the main shipping corridors used for grain exports. Mines have been detected in the territorial waters of Romania, Bulgaria, and Turkey, indicating that drift has extended beyond initial deployment zones.

The presence of mines has led to repeated disruptions of maritime traffic and increased insurance and security costs for commercial shipping. The total number of mines deployed is not publicly confirmed, but estimates place the figure in the hundreds or potentially thousands. Clearance operations are expected to take years due to the density of mines and the lack of precise records of their locations. Despite their relevance, vessels such as the Henichesk have operational limitations that affect their deployment. The ship lacks anti-surface and air defense capabilities and cannot operate independently in contested environments without protection from other naval or air assets.

Its survivability is based on reduced magnetic and acoustic signatures rather than armor or active defense systems. Operations are conducted at low speed and require stable conditions, which limit flexibility during ongoing hostilities. The minehunter is therefore more suited to post-conflict clearance or operations in secured areas. The effectiveness of the vessel is measured in the area cleared of mines, a specific contribution to ensure safe navigation in the Black Sea. The previous Henichesk (M360), for instance, was a small Yevgenya-class minesweeper of the Ukrainian Navy that was captured by Russian forces during the 2014 annexation of Crimea, returned to Ukraine, and then sunk by a Russian missile strike in the Black Sea in June 2022. 

The integration of Henichesk into Ukrainian naval operations is further constrained by legal restrictions governing access to the Black Sea. Under the Montreux Convention, the transit of warships through the Turkish Straits is limited during wartime, preventing newly transferred vessels from entering the Black Sea directly. As a result, several mine countermeasure vessels provided to Ukraine are currently based outside the country, including in the United Kingdom at ports such as Portsmouth. These vessels are being used for continued crew training, certification, and operational preparation while awaiting changes in access conditions.

This situation creates a delay between acquisition and operational deployment in the intended theater. It also limits the immediate contribution of these platforms to mine clearance operations in Ukrainian waters. Henichesk is part of a broader multinational effort to establish a Ukrainian mine countermeasure capability using transferred legacy platforms. The Netherlands has committed two Alkmaar class vessels, including Vlaardingen renamed Melitopol, while Belgium has transferred at least one mine countermeasure vessel and the United Kingdom has provided Sandown class ships such as former HMS Shoreham and HMS Grimsby.

The resulting fleet is expected to include at least five vessels equipped with NATO-compatible systems and supported by training, maintenance, and logistics programs. These ships were originally built between 1979 and 1989 and are approaching the end of their service lives, which increases maintenance requirements and limits long-term sustainability. Their transfer coincides with their replacement in donor navies by newer systems such as the Vlissingen class. The approach prioritizes rapid capability generation using available platforms rather than new construction. This allows Ukraine to build a mine countermeasure capability within a shorter timeframe despite structural constraints.

Written by Jérôme Brahy

Jérôme Brahy is a defense analyst and documentalist at Army Recognition. He specializes in naval modernization, aviation, drones, armored vehicles, and artillery, with a focus on strategic developments in the United States, China, Ukraine, Russia, Türkiye, and Belgium. His analyses go beyond the facts, providing context, identifying key actors, and explaining why defense news matters on a global scale.