France has begun developing a new version of the M51.4 intercontinental ballistic missile for French strategic submarines, Defense Minister Sebastian Lecornu announced.
According to Defense Express, the M51.4 will have increased range, increased accuracy, and improved capabilities to overcome missile defense systems compared to the current version of the M51.3. Technical specifications and development completion dates are not yet disclosed. For comparison, the M51.3 has been in development since 2014, and its production is only starting this year.
The project is expected to cost around €7.5 billion, as set out in the budget request for the current year. The M51.4 is expected to be the main armament of the new SNLE 3G submarines, which will replace the Triomphant class. The first ship of the new type is planned to be commissioned around 2035. Each submarine will carry 16 missiles, and a total of four units are planned to be built with a service life until the 2090s.
The M51 program started in 1998. Its first launch took place in 2004, and the rocket entered service in 2010. It is a three-stage solid-fuel system with a launch mass of about 53 tons and a range of over 8,000 km.
The first version of the M51.1 carried 3–6 TN-75 nuclear warheads with a yield of 150 kt. In the M51.2, these were replaced with TNO warheads with a yield of 100 or 150 kt, which are more effective in defeating anti-aircraft missiles. The M51.3 version received an upgraded TNO-2 warhead and increased range.