French SSBN-3G

The 3G SSBNs, abbreviation for Third Generation Nuclear Submarines, are nuclear submarines designed to replace the current Le Triomphant class submarines within the Strategic Ocean Force of the French Navy from 2035. The latter themselves succeeded the Le Redoutable class, which constituted the first generation of these submarines.

The historic process was initiated when the Minister of the Armed Forces, Florence Parly, announced on February 19, 2021 the notification of a five-year design contract to Naval Group and Technicatome, the main prime contractors. The total cost of the program is classified defense secret.

Construction of the first SSBN 3G class submarine will begin in 2023 at the Naval Group shipyard in Cherbourg, with commissioning scheduled for 2035. The fourth and final submarine in this series is expected to be operational in 2050, and they are planned to remain in service until 2090. Preliminary studies under the acronym FMOD (Future Oceanic Deterrence) were carried out to plan these submarines.

Regarding their technical characteristics, the 3G SSBNs will be equipped with improved versions of the M51 ballistic missile, currently in service, and will have 16 tubes for these missiles. Their tonnage will be similar to that of the Le Triomphant class so as not to require major modifications to the infrastructure of Île Longue, i.e. approximately 15,000 tonnes. The 3G SSBNs could extend by 10 meters, to be close to 148 meters in length.

The development of sonar for these submarines is entrusted to the "Underwater Systems" branch of the Thales group, and their nuclear reactor will probably be an evolution of the K15 reactor, potentially the same as that equipping the future French nuclear aircraft carrier, i.e. a K22 reactor.

These submarines will push the discretion sliders to their maximum via new technologies already proven on Suffren-type SNAs, in service since 2021.