NATO Enhances Anti-Submarine Warfare Capabilities in Baltic Sea Exercise
On board the Swedish corvette HSwMS Helsingborg, crew members executed anti-submarine warfare (ASW) drills, demonstrating the immediate readiness required in such operations. The exercise scenario involved detecting a German submarine on the surface, with supporting maritime patrol aircraft descending through cloud cover.
This engagement marked the commencement of Exercise Dynamic Merlin 26, NATO’s anti-submarine warfare exercise held in the Baltic Sea from November 9 to 13, off the coast of Sweden. Described by NATO as a “high-stakes game of hide and seek,” the exercise involved German and Swedish submarines attempting to evade detection by warships, helicopters, and maritime patrol aircraft from eight participating nations, including the United Kingdom, United States, Canada, Netherlands, Denmark, and Finland.
Evolution to Dynamic-Series Exercise
Historically, Merlin functioned as a smaller-scale training event. This year, for the first time, it was elevated to a full Dynamic-series exercise, aligning it with NATO’s larger anti-submarine exercises conducted in the North Atlantic and the Mediterranean.
Rear Admiral John Craddock, a U.S. Navy officer commanding NATO’s submarine forces, elaborated on this evolution. “Before, it was a playbook, kind of working through some basic level exercises and some scenarios,” he stated. “Now that it’s dynamic, [we’re] being able to bring it up to a more advanced level, to really challenge the interoperability of the crews, the ships, helicopters, to work together on a common problem set.”
The Baltic Sea is frequently characterized by military strategists as contested, congested, and confined. Rear Admiral Craddock affirmed these descriptions, emphasizing the necessity of visible operations. “We have to make sure that everyone sees that we can do these operations, that we can demonstrate the interoperability, that we can show deterrence through those exercises,” he explained.
Operational Challenges of the Baltic Sea
The Baltic Sea presents one of the most complex environments globally for submarine detection. Its unique hydrological conditions, including shallow depths, high shipping traffic, and layers of cold river water that distort sound, significantly impede sonar effectiveness.
Rear Admiral Johan Norlén, Chief of the Royal Swedish Navy, highlighted these challenges at a pre-exercise press conference in Stockholm. “The confined area here is actually the tricky part. The bottom is always in play,” he said, calling the Baltic “a very unique and in some ways extreme area” and “a hotspot for some time now.”
The constant flow of commercial and civilian vessels in the Baltic adds another layer of complexity. During one flight, the crew of a Canadian helicopter observed approximately 60 ships within an hour. Craddock noted that managing this traffic is an integral part of operations. “We have to have that awareness of red dots, blue dots and white dots, to understand where everyone is, and then to protect shipping, and to minimise any kind of collateral damage to other vessels,” he stated.
Incidents involving undersea infrastructure in the Baltic Sea have recently drawn international attention. Days before the exercise, a Finnish court sentenced the Russian captain of the cargo ship Fitburg for damaging telecommunications cables between Finland and Estonia by dragging its anchor. Rear Admiral Craddock stressed that safeguarding undersea infrastructure begins with comprehensive awareness. “Understanding who, what ship is what, what they’re doing. […] Part of this exercise is to get out there and build that picture, both above the water and then through submarines and other technology under the water,” he affirmed.
Standing NATO Maritime Group One at the Core
The central operational unit for the exercise was Standing NATO Maritime Group One (SNMG1), comprising five ships from the Netherlands, Germany, Canada, Denmark, and Finland. The group was under the command of French Rear Admiral Nicolas Molitor.
Rear Admiral Molitor outlined the group’s primary objectives: “The main objective is also, of course, working on interoperability. So it’s about tactics, it’s about techniques, and to see how we can best integrate with allies.” He added, “And of course, this all in the overarching aim is to show NATO’s unity and its ability to deter and act and operate whenever necessary.”
He further observed that the exercise integrated two distinct types of naval forces: “We have the blue water navies, which are used to working in the Atlantic Ocean with deep waters, and we are here in an environment where the waters are […] very, very shallow, and this is very specific.”
The group’s training protocols are planned by Royal Navy officer Lieutenant Commander Jonny Miller. He emphasized that NATO’s standardized procedures enable allied navies to collaborate effectively with minimal prior notice. “If I’m driving my task group, sorry, I went full RN there, driving my task group through an open patch of water and I just encounter an ally, we have that ability to pick up the radio, get on the chat, and just say, ‘Hey, we’re going the same place. Do you want to do some training together?'” For Miller, the fundamental purpose of these exercises is straightforward: “Deterrence is really the keystone of what NATO does. We are watching what is going on, and if necessary, we can respond to what’s going on.”
On board the Dutch tanker leading a NATO task force
The Tanker as a Command Ship
Unusually, the flagship for SNMG1 was not a destroyer or a frigate, but a replenishment oiler: HNLMS Den Helder. This vessel, the Royal Netherlands Navy’s newest ship, entered service in October 2023 and was undertaking its first role as a NATO command ship during the exercise.
The HNLMS Den Helder is equipped with an advanced bridge, featuring multiple screens, and has been likened by some personnel to the “Starship Enterprise.” It possesses a capacity for approximately eight million liters of fuel and can refuel ships on both sides simultaneously, while also accommodating an admiral and a multinational staff of eight nations.
Commander Cleo Ten Hoopen, the ship’s commanding officer, commented on its capabilities and the experience of hosting a diverse staff. “It’s brand new. It’s the first time having a staff on board, so it’s good […] just to see what the ship is capable of, just to see what we can do, what we can’t do.” She attributed the success of the multinational collaboration to effective communication: “We eat in the same room and we talk. Well, we have to talk a lot with each other. And I think, we’re Dutch. We’re used to having other countries on board.”
Canada’s Contribution to Submarine Hunting
Participating alongside the HNLMS Den Helder in Stockholm was HMCS Ville de Québec, a Canadian Halifax-class frigate. In service for over 30 years and deployed since July, it is one of only two Canadian frigates fitted with an upgraded towed sonar system. The frigate also operates a CH-148 Cyclone helicopter, which its crew estimates can survey “nearly half the Baltic” in a single flight.
Commander Jason Knowles, the commanding officer, noted the adaptation required for a ship designed for the deep waters of the North Atlantic to operate in the Baltic. “Ville de Québec is designed as an anti-submarine frigate, and thus this is really our bread and butter. However, we are designed to operate in the North Atlantic, so it’s important to come to a different part of the world, train, and understand the waters here.”
Commander Knowles emphasized the importance of demonstrating operational presence. “You need to demonstrate to both your own populace as well as any potential adversaries that you are continuing to train, continuing to develop, continuing to improve your awareness and understanding of how to operate in that complicated battle space.” He also acknowledged the inherent challenges of ASW, stating that submarines “are inside the environment and understand it so much better than we do. We’re only on top of it,” and conceded that occasionally, the submarine successfully evades detection.
The involvement of Sweden, hosting the exercise in its home waters, underscores the nation’s increasing integration into NATO defense planning and its strategic importance in the Baltic Sea region. The exercise provided invaluable experience for all participating nations in a complex and strategically vital maritime domain.
Why This Matters
Exercise Dynamic Merlin 26 holds significant implications for regional security, NATO’s operational readiness, and the broader geopolitical landscape:
- Enhanced Deterrence and Collective Defense:In an era of heightened geopolitical tension, particularly following Russia’s full-scale invasion of Ukraine, exercises like Dynamic Merlin 26 demonstrate NATO’s commitment to collective defense. By publicly conducting advanced ASW operations, NATO signals its capability and resolve to protect allied territories and interests, acting as a deterrent against potential aggression in the Baltic Sea region.
- Critical Interoperability:The ability of multiple nations’ naval forces, with diverse equipment and doctrines, to operate seamlessly is paramount for NATO’s effectiveness. This exercise specifically focused on challenging and improving interoperability in complex ASW scenarios, ensuring that allied crews, ships, and aircraft can integrate swiftly and efficiently during real-world crises.
- Strategic Importance of the Baltic Sea:The Baltic Sea is a vital maritime corridor, critical for trade, energy, and security for littoral states. Its unique environmental challenges (shallow, crowded, acoustically complex) demand specialized training. Mastering operations in this “hotspot” is essential for maintaining freedom of navigation and protecting the interests of NATO members and partners in a strategically sensitive area adjacent to Russia.
- Protection of Undersea Infrastructure:Recent incidents of damage to vital undersea cables highlight the vulnerability of critical communication and energy infrastructure. ASW exercises contribute directly to developing capabilities to monitor and protect these assets from sabotage or interference, thereby safeguarding economic stability and national security for the region.
- Adaptation to Complex Environments:The exercise provided invaluable experience for “blue water navies” accustomed to deeper oceans to adapt their tactics and technologies to the shallow and congested Baltic. This continuous learning and adaptation are crucial for NATO forces to maintain superiority across all operational environments.
- Integration of Key Partners:The active participation of Sweden, hosting the exercise in its territorial waters, reinforces its crucial role in regional security and its deepening integration with NATO defense planning. This collaboration strengthens the overall defense posture of the Baltic Sea area, especially in light of new NATO memberships.
A recent NATO naval exercise in the Baltic Sea brought together allied navies, with a significant focus on the integration and capabilities of Sweden, the alliance’s newest member. The exercise, conducted in waters that are strategically vital and geographically complex, aimed to enhance interoperability and readiness across multiple domains of modern naval warfare.
For many participating navies, the Baltic Sea presents unique operational challenges due to its relatively shallow waters, intricate archipelagos, and fluctuating environmental conditions. In contrast, the Royal Swedish Navy possesses extensive familiarity and operational expertise within this specific maritime environment, making its contributions particularly valuable to the collective defense efforts of the North Atlantic Treaty Organization.
One of the key Swedish assets participating was HSwMS Helsingborg, a Visby-class corvette. This vessel, measuring 73 meters in length and constructed from radar-scattering carbon fiber, is designed for stealth and high maneuverability. Operated by a crew of approximately 45, its primary weapon systems are integrated within the hull to maintain its low-observable profile. The Visby class is slated to receive the British-designed Sea Ceptor air defense missile system, a significant enhancement to its defensive capabilities.
The commanding officer of HSwMS Helsingborg, Theresia (surname not provided in original source), articulated the significance of the exercise. She noted that Sweden’s accession to NATO in 2024 has not altered the fundamental operational procedures of the Swedish Navy within the Baltic Sea. Instead, she emphasized that the change lies in the framework of cooperation, stating, “It has changed in the way that we are operating together with our allied partners within the framework of NATO.” This highlights a continuity of expertise combined with a new context of collective security.
Lieutenant Commander Norlén of the Swedish Navy further elaborated on Sweden’s role, presenting the exercise as an opportunity for the Royal Swedish Navy and the broader Swedish Armed Forces to demonstrate their specific contributions to NATO. He particularly underscored Sweden’s capabilities in the underwater domain, an area of critical importance given the strategic challenges in the Baltic Sea.
Beyond Submarine Warfare: Addressing Multi-Dimensional Threats
While subsurface warfare, specifically anti-submarine warfare (ASW), formed a central component of the exercise, the training scenarios extended to encompass a broader spectrum of contemporary naval threats. This year’s iteration included live drone attack simulations, conducted without prior warning to the ships. This element was designed to test the rapid detection, reaction, and engagement capabilities of the participating vessels under realistic pressure.
German Navy Captain Molitor, who served as Commander of Task Group 441.01 and directed the exercise, emphasized the principle of “training as we fight.” He explained that the aim was to expose ships to real-life situations, observe their ability to detect incoming threats, react appropriately, and neutralize targets. This approach ensures that crews are prepared for the unpredictable nature of modern combat.
Lieutenant Commander Norlén further highlighted the complexity of modern naval engagements, stating, “We always talk about drones or anti-submarine warfare or missiles. The bottom layer here is that we are here to test and train together in all three dimensions at the same time. That is what makes it really complex.” This multi-dimensional approach reflects the evolving threat landscape, where naval units must simultaneously contend with threats from above (drones, missiles), on the surface, and below the surface (submarines).
Operational Execution and Strategic Significance
During the exercise, the operational tempo remained high. Patrol aircraft conducted sorties, providing aerial surveillance and support. A Canadian helicopter deployed its dipping sonar system, actively searching for simulated submarine threats, underscoring the multinational nature of the ASW efforts. Across the horizon, various NATO warships maintained their operational stations, forming a cohesive and integrated force. This comprehensive deployment of assets, from stealth corvettes to specialized ASW helicopters and patrol aircraft, demonstrated the breadth of capabilities within the alliance.
The exercise concluded with ships returning to base, their crews having sharpened their skills through demanding and realistic training. The observed professionalism and focused determination of the Swedish sailors, particularly in the context of their nation’s recent NATO membership, conveyed a clear message of readiness and seamless integration. The Swedish Navy has not merely begun to adapt to NATO standards; it has demonstrated a robust and proficient integration of its operational capabilities and doctrines within the alliance’s framework, reinforcing NATO’s collective defense posture in the critical Baltic Sea region.
This comprehensive training, spanning multiple domains and involving diverse national assets, underscores NATO’s commitment to maintaining a robust defensive capability and ensuring interoperability among its member states in an increasingly complex security environment.
Why This Matters
The recent NATO naval exercise in the Baltic Sea, featuring Sweden as a new member, carries significant geopolitical and strategic implications for regional and international security. Its importance can be understood through several key dimensions:
Enhanced Collective Defense and Deterrence in the Baltic Sea
The Baltic Sea is a critical geopolitical flashpoint, bordering several NATO members and Russia. Sweden’s accession to NATO, following that of Finland, has fundamentally altered the strategic landscape, effectively transforming the Baltic Sea into what some refer to as a “NATO lake.” This exercise demonstrates the alliance’s commitment to reinforcing its collective defense posture in this vital region. By conducting complex, multi-dimensional training, NATO sends a clear message of deterrence against potential aggression, signaling its capability and resolve to defend every inch of allied territory, including its maritime domains. The presence of numerous NATO warships, alongside specialized assets, emphasizes the alliance’s robust response capacity.
Sweden’s Strategic Value and Seamless Integration
Sweden brings substantial strategic value to NATO, particularly its deep expertise in operating within the unique environmental conditions of the Baltic Sea. Its advanced naval assets, such as the Visby-class corvettes, are highly suited for operations in coastal and archipelago environments. The exercise showcased Sweden’s rapid and effective integration into NATO’s operational framework, demonstrating that its forces are not just adapting, but are already proficient in conducting joint operations with allies. This seamless integration enhances NATO’s overall readiness and operational effectiveness, especially in a region where Sweden’s historical neutrality has now been replaced by active participation in collective security.
Addressing Evolving Threats in Modern Naval Warfare
The inclusion of live drone attack simulations and the emphasis on simultaneously tackling anti-submarine warfare (ASW), anti-drone, and anti-missile threats highlight NATO’s understanding of the evolving nature of modern naval warfare. Subsurface capabilities remain a significant concern, particularly in enclosed seas like the Baltic. Simultaneously, the proliferation of unmanned aerial and surface systems presents new challenges to naval defense. By training against these complex and multi-layered threats, NATO ensures its forces are prepared for the full spectrum of potential engagements, moving beyond traditional warfare paradigms to address hybrid threats effectively. This proactive approach to training is essential for maintaining a technological and tactical edge.
Strengthening Interoperability and Alliance Cohesion
Exercises of this nature are fundamental for building and maintaining interoperability among allied navies. They allow different national forces, operating under varied doctrines and with diverse equipment, to learn to communicate, coordinate, and execute complex maneuvers seamlessly. The involvement of assets from multiple nations, such as Swedish corvettes, German command elements, and Canadian ASW helicopters, illustrates the practical application of alliance cohesion. This shared experience fosters trust, refines joint procedures, and strengthens the overall effectiveness of NATO as a unified defensive alliance. It ensures that should a real-world contingency arise, allied forces can act as a coherent and formidable unit.
Reinforcing Regional Stability and Security
Ultimately, these exercises contribute to broader regional stability and security. By demonstrating strong collective defense capabilities and a unified front, NATO helps to deter aggression and reassure its member states. The heightened presence and robust training activities in the Baltic Sea underscore the alliance’s commitment to safeguarding the security interests of its members in Northern Europe, ensuring freedom of navigation and upholding international law in strategically important waters. This sends a clear signal that the security of the Baltic region is a non-negotiable priority for NATO as a whole.