Kulisy of the participation of submarine Isaac Peral in Operation "Sea Guardian"

A prototype submarine Armada Española S-81, Isaac Peral, he began his first participation in Operation North Atlantic Alliance. The unit equipped with internal combustion engine, currently operates in the Mediterranean Sea in the NATO permanent team "Sea Guardian". The purpose of this operation is to maintain maritime safety, counter terrorism and protect critical infrastructure in the region.

Spanish submarine debut Isaac Peral in Operation "Sea Guardian"

As we've already reported on our portal Pond a week ago, ESPS Isaac Peral began to participate in Operation "Sea Guardian". Then we described the unit's debut without going into detail. This time we look closer at the tasks it performs in the mission, which technical solutions it uses and whether this is relevant to the programme Eagle. Now, based on the development of the service Naval News and available materials NATO MARCOM, our editorial board presents an equally detailed and substantive analysis of the share of the Spanish submarine Isaac Peral on this mission.

As reported by NATO Marine Force Command (MARCOM), Isaac Peral is part of the so-called "Associated Support" in Operation "Sea Guardian". The ship carries out situational reconnaissance tasks, including maritime surveillance and the collection of data relevant to maritime situational awareness (MDA). MARCOM commander, Lieutenant Commander Arlo Abrahamson, stressed in an interview with the portal Naval News‘This unit contributes to a better understanding of the marine environment — both from the surface, from the air and from below the water. It is a modern ship that increases NATO's ability to maintain a high level of situational recognition."

🔗 Read more: S-80 Spanish submarine debut at Operation Sea Guardian

The ship was transferred to service in November 2023 and is a prototype unit of the S-80 Plus program, implemented by the Navantia shipbuilding company. His participation in the operation Sea Guardian confirms full operational readiness and the ability to integrate into NATO's command structure. Simultaneously Isaac Peral remains under the national operational control of Spain, in accordance with the rules in force for entities carrying out Alliance missions in the framework of national operations.

Operation "Sea Guardian" is carried out in the Mediterranean waters in permanent mode, using the so-called "FOCOP" cycle.

FOCOP operations are carried out where there is a need to strengthen the Alliance's situational awareness and deepen knowledge of the marine environment. With this, NATO builds a comprehensive picture of maritime activity, supports cooperation with regional partners and develops interoperability of forces.

kmdr Lt. Arlo Abrahamson

Capability and equipment of S-80 Plus ships

The S-80 Plus program includes the construction of four conventional new generation submarines. The first one is ESPS Isaac Peral (S-81) and subsequent units – S-82 Narciso Monturiol, S-83 Cosme García and S-84 Mateo García de los Reyes – are located at various stages of construction at the shipyards in Cartagena.

According to the data published in the study Janes, which constitutes a compendium of knowledge about the structure and potential of the maritime forces of the countries of the world, the admission to service of subsequent S-80s is planned for a two-year cycle starting in 2026. Second ship, S-82 Narciso Monturiol, was first launched in March 2025, baptized a month ago, and is currently being prepared for launching.

Isaac Peral and units of this series have been designed to carry out reconnaissance and patrol activities in maritime safety operations, both on the surface and underwater. It uses the L3Harris Mod 2010 OS optoelectronic mast and the integrated sonar system developed by Lockheed Martin. The set includes a cylindrical mid-frequency L3Harris antenna, two side low-frequency passive antennas, a towed very low-frequency antenna SAES Solarsub with the ability to roll, as well as distance capture and measurement systems.

As the spokesman for the Navy of Spain stressed, the combination of these systems with a design with reduced acoustic detection, a wide range of activities and a wide range of exploratory data collection, significantly increases the individual's surveillance, protection and situational awareness at sea. It is also particularly important to be able to communicate with satellites, allowing for the current exchange of data and coordination of NATO activities.

The next S-80 type units will receive a new air-independent propulsion system (AIP), based on BEST (Bio-Ethanol Stealth Technology). This solution will increase the autonomy and stability of ships during long-term immersion. The AIP system will be introduced on the third and fourth ships of the series and then, as part of planned modernization, mounted on the first two units. S-80-type ships, 80 metres long and about 3000 tonnes buoyant, are intended to constitute a new generation of Spanish submarine forces, providing NATO with modern capabilities in the Western Mediterranean region.

Operation preparation and first combat use

During the Combined Naval Event 2025 conference held in May in Farnborough, British submarine program manager Navantia, José Luis Saez, reported that the air-independent drive system of the BEST (Bio-Ethanol Stealth Technology) used in S-80 Plus type units would allow you to remain submerged for up to three weeks.

A spokesman for the Spanish Navy confirmed that ESPS Isaac Peral has reached full operational readiness. The final stage of preparation for service included a comprehensive technical assessment of ship systems, qualifying sea trials and crew testing in scenarios simulating real combat conditions. As part of these activities, the unit carried out two mid-range missions from the home port of Cartagena to confirm its ability to operate autonomously, safely and effectively.

🔗 Read also: Are Spanish S-80 submarines a good proposition for Poland?

First operational use Isaac Peral took place in the waters off the coast of Galicia in north-western Spain, where the ship participated in the "Dynamic Mariner" exercises organised by NATO Marine Force Command (MARCOM). The purpose of the maneuvers was to improve the allied capacity to respond to crisis situations in a multi-domain environment not covered by Article V of the North Atlantic Treaty.

In the course of the training cycle, the unit took part in the "FLOTEX 25" exercises commanded by the Spanish Navy, followed by an episode of "SINKEX" in the waters of the Canary Islands, during which the procedures for the use of arms against water targets were tested.

According to spokesman Armad Española, participation Isaac Peral in Operation "Sea Guardian" confirms the technical maturity of the S-80 Plus programme and Spain's contribution to developing NATO's potential as a supplier of modern, interoperable submarine capacity.

Operation "Sea Guardian" was established by decision of the NATO Summit in Warsaw in 2016 as an initiative of wider maritime security, continuing the anti-terrorism mission "Active Endeavour", conducted after the terrorist attacks on the United States of America of September 11, 2001.

NSM for submarines – Spanish path, Polish need

Today it is worth recalling something about which Polish media speaks scarcely. Part of the naval environment has over the years stressed the need for missiles maneuvering on submarines, but today this issue is silent. Meanwhile, the Spanish direction – NSM and Navantii's cooperation with Kongsberg – shows that long-range weapons become a standard. The Spanish choice of NSM manoeuvring missiles and Navantii's cooperation with the Norwegian company Kongsberg show that the ability to destroy water and land targets is now one of the key elements in building the potential for deterrence. Agreements concerning the implementation of the NSM on S-80 type units constitute a precedent that could also benefit from Polish Navy Poland under the Orka programme.

For Poland, located in the immediate vicinity of the Russian Federation, the possibility of equipping future submarines with maneuvering missiles should undoubtedly be strategic. It increases the real extent of the influence of the marine forces, allows to conduct precise strikes into the enemy's territory and hinders the planning of Russian maritime activities in the Baltic. Ships with such weapons would be counterweight and a full-value element of the deterrence system, strengthening Polish participation in securing the northern flank of NATO. Importantly, it would be possible to acquire such capabilities within a relatively short time period.

Naval News editorial comment – the importance of S-80 Plus for NATO

Early ESPS involvement Isaac Peral NATO is a clear proof of the operational benefits of bringing new types of submarines into service in allied structures. S-80 Plus units increase not only the potential of the Spanish Navy, but also the overall potential of the Alliance's submarine forces in the Mediterranean.

The former Armada Española submarine class – four S-70s Galerna (Agosta) – was largely decommissioned. Only ESPS remains in service Galerna, carrying out training and patrol tasks. In Spain, however, discussions are underway on the possibility of increasing the number of submarines to six units, indicating the growing importance of the submarine domain in the national maritime strategy.

🔗 Read also: Combat potential of S-80 ships in Orka program [WIND]

New submarines are also an important deterrent element in the south-western NATO operating area. The units stationed in Cartagena will carry out operations near the strategic bottlenecks – the Strait of Gibraltar, which controls the western entrance to the Mediterranean Sea. From the point of view of the Alliance, the presence of modern S-80 ships In this area, it significantly strengthens the exploratory and countering capabilities of third countries.

It is worth recalling that after the outbreak of the Russian-Ukrainian War in 2022 Turkey applied the provisions of the 1936 Montreux Convention, limiting the flow of combat units through the Straits of Bosfor and Dardanele. As a result, Russian submarines based outside Novorossian lost their freedom of movement between the Black Sea and the Mediterranean. In addition, after the loss of the Russian logistical facilities in Syria in 2024, any conversion of Russian nuclear-powered vessels to the Mediterranean Sea requires passage through the Strait of Gibraltar – under the supervision of Spanish naval forces and their new submarines.

In this way, the S-80 Plus programme not only modernises the Spanish fleet but also strengthens the Alliance's ability to monitor and control the movement of submarines in one of the most strategically important maritime areas in the world.

Source: Naval News/Adam Woznicki