France submits Blacksword Barracuda submarine proposal to Greece for 2035 Eastern Mediterranean operations.

France’s Naval Group has submitted its Blacksword Barracuda conventional submarine to Greece, aiming to equip the Hellenic Navy with enhanced long-range undersea strike and surveillance capabilities for operations in the Aegean and Eastern Mediterranean.

The proposal supports a four-submarine program to replace legacy Type 209 submarines, introducing lithium-ion battery propulsion and expanded multi-mission payload capacity to improve endurance, mobility, and operational flexibility. The offer targets a 2035 entry into service following a 2028 contract decision, with construction involving Greek industry partners and integration into a mixed submarine fleet. The program reflects Greece’s shift toward extended-range missions and A2/AD operations, strengthening deterrence, ISR reach, and strike capability in a contested maritime environment.

Related news: Greece to announce modernization of four Papanikolis-class submarines with new acquisitions under consideration

The Blacksword Barracuda is based on the architecture of the Suffren-class nuclear submarine but adapted to a diesel-electric configuration, allowing it to retain the same hydrodynamic characteristics and internal layout. (Picture source: Naval Group)

As reported by OnAlert on April 8, 2026, the French Naval Group submitted its Blacksword Barracuda proposal to the Hellenic Navy, as part of a four-submarine program intended to replace Type 209/1100 and Type 209/1200 units that have been in service for close to five decades, following a request for information issued in late 2025 and answered in December 2025. The program targets an initial operational capability by 2035, which implies a contract signature by 2028, given a construction timeline estimated at five to six years per first unit. The Greek submarine fleet currently includes four Type 214/1600 submarines, one upgraded Type 209/1500 AIP unit, three Type 209/1200s, and one Type 209/1100, creating a mixed architecture with different propulsion systems and maintenance requirements.

Competing proposals are expected from Germany's TKMS with Type 212CD or Type 218 derivatives, Sweden's Saab with the A26, and South Korea with the KSS-III, placing the French offer within a multi-vendor evaluation framework. The program's operational requirement reflects a shift in geographic scope and mission profile, as Greek submarine operations would extend from the Aegean Sea toward the Eastern Mediterranean, increasing patrol distances and time on station. The mission set includes Anti-Access and Area Denial (A2/AD) operations; Intelligence, Surveillance, and Reconnaissance (ISR) missions; and land-attack capability, requiring a balance between endurance, survivability, and strike capacity.

The Greek requirement also specifies reduced acoustic, magnetic, and active sonar signatures, along with a lower indiscretion rate to minimize exposure during long deployments. The integration of lithium-ion batteries is explicitly included alongside AIP in baseline requirements, indicating a transitional phase in propulsion systems rather than a strict continuation of existing configurations in service. Payload flexibility is also a requirement, with integration of torpedoes, cruise missiles, unmanned aerial vehicles (UAVs), and unmanned underwater vehicles (UUVs) considered necessary for future operations. The Blacksword Barracuda, launched in 2024 by Naval Group, is derived from the French Suffren-class nuclear attack submarine but reconfigured with a conventional diesel-electric system, maintaining hull geometry and internal layout principles.

The submarine has a length of 82 meters and a submerged displacement of about 3,300 tons, positioning it above most conventional submarines currently in Greek service in terms of size and internal volume. Crew size is about 35 personnel, with accommodation for an additional five to six special operations forces, indicating the integration of special missions from the design phase. Maximum submerged speed is estimated at 20 knots, with an operational range of about 15,000 nautical miles and total endurance up to 70 days, constrained primarily by consumables rather than propulsion limits. The Blacksword Barracuda also includes six 533 mm torpedo tubes and a total payload capacity of about 30 weapons, integrated through the Subtics combat system, which manages sensors, weapons, and mission data. 

The propulsion system removes air-independent propulsion (AIP) modules entirely and replaces them with lithium-ion battery arrays, increasing available onboard energy while simplifying the propulsion architecture. Lithium-ion batteries provide higher energy density compared to lead-acid counterparts, allowing more energy storage within the same volume, with faster recharge cycles measured in hours rather than extended AIP endurance cycles. Lifecycle performance is increased by up to 40 percent, reducing replacement frequency over the submarine’s service life. Submerged endurance without snorkeling is estimated between 10 and 15 days, depending on operational speed, with battery recharge conducted through diesel generators using a snorkel mast.

AIP systems, which rely on stored reactants such as hydrogen or ethanol, enable longer low-speed endurance but require dedicated refueling infrastructure and introduce additional complexity that affects maintenance and availability. The operational impact of this configuration is a shift from endurance-based stealth toward mobility-based survivability, with the Blacksword Barracuda submarine capable of maintaining higher submerged speeds for longer periods without rapidly depleting energy reserves. Sustained speeds in the 15 to 20 knot range are feasible over operationally relevant durations, reducing transit time between patrol areas and allowing more flexible mission execution.

Snorkeling is still required for battery recharge, but the duration of exposure is reduced due to faster charging, which limits vulnerability to anti-submarine warfare (ASW) assets during this phase. The submarine can alter mission profiles after deployment, including repositioning or changing engagement priorities, without being constrained by strict low-speed endurance requirements. Total mission duration remains limited by crew endurance, fuel reserves, and onboard supplies rather than battery capacity alone. Acoustic performance is addressed through structural and mechanical isolation measures, including raft-mounted machinery to reduce vibration transmission and a hull form optimized for hydrodynamic efficiency based on the Albacore profile.

These features are intended to reduce flow noise and mechanical noise across a range of speeds, including higher-speed transit phases that are typically associated with increased acoustic signatures in conventional submarines. The design objective is to maintain low detectability not only during low-speed patrol but also during repositioning maneuvers, which would reduce exposure during operational movement. This approach challenges the conventional trade-off where submarines reduce speed to minimize acoustic signature, although validation of performance under operational conditions remains a key factor in evaluation. The weapons configuration of the Blacksword Barracuda includes six torpedo tubes supporting a payload of about 30 weapons, with integration of F21 heavyweight torpedoes, anti-ship missiles such as Exocet SM40, and cruise missiles such as MdCN for land-attack missions.

The inclusion of cruise missiles introduces a strike capability against land targets at extended range, expanding the role of the submarine beyond anti-surface and anti-submarine warfare. Additional payload options include naval mines and unmanned systems, including unmanned underwater vehicles, enabling surveillance and reconnaissance missions without exposing the submarine directly. The configuration supports a transition from a platform focused on sea denial to one capable of multi-domain operations, combining strike, surveillance, and special mission capabilities within a single design. Industrial participation is structured through a Hellenic Industrial Participation framework, with more than 120 contracts already signed with over 70 Greek companies since 2022, linked to existing naval cooperation programs.

For the submarine program, METLEN is positioned to manufacture hull sections while Skaramangas Shipyards is designated for final assembly, enabling domestic construction capability. Construction options include full production in Greece or a hybrid approach with the first unit built abroad and subsequent units assembled locally, depending on contractual arrangements. The timeline assumes first delivery within five to six years after contract signature, aligning with a 2035 entry into service if agreements are concluded by 2028. Maintenance and lifecycle support are planned to be conducted within Greece, reducing reliance on external facilities and integrating domestic industry into long-term sustainment activities.

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.