France’s defence ministry confirmed the first submarine launch of the M51.3 ballistic missile from the Navy’s SSBN Le Vigilant, with the unarmed test carried out off Finistère in western France. President Emmanuel Macron watched from a frigate as the firing completed an acceptance trial after a major maintenance overhaul, validating the submarine’s return to the operational deterrence cycle.
The missile fell into the North Atlantic several hundred kilometres from any coast, and the ministry said the launch complied with France’s international commitments. The test was the first time the M51.3 has been launched from a submarine, following its entry into service in October 2025 as part of the modernisation of France’s sea-based nuclear force.
Le Vigilant’s firing forms part of the rollout of the latest M51.3 variant across the Triomphant-class SSBN fleet, which carries France’s strategic sea-based deterrent. The exercise was designed to certify the submarine’s ability to deploy the weapon after a long maintenance and modernisation period, with public details limited on the missile’s flight profile and technical performance.