The final French Triomphant-class nuclear-powered ballistic missile submarine, Le Téméraire, has been docked at the Brest naval base to begin modifications that would allow the submarine to launch M51 nuclear ballistic missiles. The M51s will replace the obsolete and soon-to-be out of service M45 missiles that previously armed the SSBNs in the French fleet. DCNS Group, the French defense company undertaking the modifications, will spend the next 18 months laying over 140 km of cables and welding some 60 tons of engine seating to complete the transformation. Michel Drevillon, the program manager overseeing the refit, announced that the project would take 4 million of hours of work and will include upgrades to the submarine’s navigation and combat systems.