France Prepares First M51.3 Ballistic Missile Launch in Three Years

France is preparing to conduct its first M51.3 intercontinental ballistic missile test launch in three years. The missile will be launched from the French nuclear-powered ballistic missile submarine Le Vigilant.

French newspaper Ouest-France reported the development.

Strategic weapons analyst Étienne Marcuez said the missile is expected to travel around 4,700 km during the test. However, he stressed that 4,700 km is not the M51.3’s maximum range.

The missile is expected to be launched without a nuclear warhead off the coast of France’s Finistère department. Maritime restrictions have already been imposed in the area and will remain in effect until October 21.

France’s preparations for the M51.3 ballistic missile launch come after the completion of extensive maintenance work on the submarine Le Vigilant. The overhaul began in autumn 2023 at the Île Longue naval base and included work on the submarine’s reactor, weapons systems, and other equipment.

Following such an overhaul, French strategic submarines undergo sea trials, while the M51 launch is intended to confirm the operational readiness of the strategic weapons system. Le Terrible conducted a similar launch in April 2023 after completing its IPER overhaul.

In October 2025, as Militarnyi previously reported, the M51.3 officially entered operational service. The new variant features improved range, accuracy, and capabilities to penetrate missile defenses. It can also carry the new TNO-2 nuclear warhead.

France conducted the first qualification test launch of the M51.3 version in November 2023 from the ground-based test facility at Biscarrosse. The missile was also launched without a nuclear warhead and flown toward the Atlantic Ocean.

M51.3 Ballistic Missile

The M51.3 is a three-stage, solid-fuel, submarine-launched intercontinental ballistic missile developed as a further evolution of the M51 missile family.

The exact specifications of the new variant have not been disclosed. For previous M51 versions, the missile’s range has been estimated at approximately 8,000–10,000 km, with a maximum speed of up to Mach 25. The M51.1 and M51.2 versions could carry thermonuclear warheads with yields of approximately 110–300 kilotons.

The M51.3 is believed to retain the basic dimensions of its predecessors: about 12 meters long, 2.3 meters in diameter, and a launch mass of around 52 tonnes. For navigation, the missile uses, among other systems, Europe’s Galileo satellite navigation system.

The M51.3 is also being considered as the primary weapon system for France’s next-generation SNLE 3G strategic nuclear-powered ballistic missile submarines, which are expected to gradually replace the Le Triomphant-class submarines after 2035. The M51 missile family is developed and manufactured by the French company ArianeGroup.