PARIS — France has launched the program for its Navy’s third-generation nuclear-powered ballistic missile submarines, which will see four vessels eventually delivered to the service.

The Navy is expected to received the first submarine in 2035, with the other three following at a schedule of one every five years.

These four boats, known in France as SNLE (sous-marin nucléaire lanceur d’engin) “will replace the current [ones] without a break,” Armed Forces Minister Florence Parly announced last week.

She said the subs will sail until 2090. “The last sailors to patrol on this SNLE third generation have not yet been born.”

The contracting authorities are the DGA procurement agency and the Alternative Energies and Atomic Energy Commission. The project management will lie with Naval Group and TechnicAtome, the latter being the prime contractor for the nuclear boiler room.

Thales announced it signed a memorandum of understanding with the DGA for the development of a complete sonar suite for the boats “based on disruptive technologies that represent a significant break from the systems in service today.” The company will provide new-generation flank arrays and bow-mounted sonars; a towed linear array based on optical technology; as well as intercept arrays, echo sounder technology and underwater telephones. The company said the new sonar suite will be incrementally deployed, with the first versions installed on the current SNLEs.

Parly said the new submarines will be “slightly longer and heavier” than the current Le Triomphant class, which first sailed in 1995 and will continue to do so until 2050. She added that the vessels will “hear better and defend themselves better whilst at the same time being more silent: They will not make more noise than a school of shrimp.”

Parly noted that given the extreme length of this program, France will “maintain a margin for evolutions [in the design], indispensable to take account of technological breakthroughs that we cannot forecast today — I’m thinking notably of cyber defense, improvements in acoustic stealth and the development of better-performing sensors.”

Parly announced the launch of the program at the DGA’s hydrodynamic technologies center at Val-de-Reuil where all the French Navy’s submarines have been designed and evaluated over the past 60 years, and where work on this third generation of SNLEs has already been underway for more than a decade.

“Fifteen million hours have already been spent on development studies, and a further 20 million will be necessary for each submarine,” she said.

She partly credited the program existence with the hydrodynamic technologies center’s 2017 acquisition of computer technology know-how.

The minister also noted that in a few weeks the DGA will celebrate its 60th anniversary. “The world has undergone deep changes since 1961,” she said, “but if the ways of making war are no longer the same, those of keeping the peace remain. As the president confirmed [in February 2020], nuclear deterrence is and remains the keystone of our security and the guarantee of our vital interests.”

She noted that 2021 also marks the 50th anniversary of the permanent patrols of France’s nuclear-powered ballistic missile submarines, a mission she likened to “a rocket launch pad, a real underwater Kourou [the space base in French Guiana] with 16 rockets ready to go, all integrated into a combat submarine propelled by a nuclear power station.”

Christina Mackenzie was the France correspondent for Defense News.

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