France’s Ministry of the Armed Forces said the nuclear-powered submarine Le Vigilant, which carries ballistic missiles, successfully fired an M51.3 missile without a nuclear charge off Finistère on Tuesday, October 6.
Under Operation Smertrios, the launch served as an acceptance test, checking whether, after a major maintenance and modernisation period, the submarine could once again use its strategic weapon system.
The firing was the first launch of the M51.3 version from a submarine. The variant entered operational service on October 24, 2025, following a land-based qualification flight in November 2023.
The Directorate General of Armaments (DGA) said its missile-test resources tracked the missile throughout its flight, including the test and measurement ship Monge. The impact area was in the North Atlantic, several hundred kilometres from any coast.
Naval Group said work on Le Vigilant’s overhaul started at Île Longue in autumn 2023, when its weapons and nuclear-reactor fuel were removed. It then underwent 18 months of work in dry dock at Brest before arriving back at Île Longue on July 18, 2025, for the final maintenance stage.
The M51.3 is the third iteration of France’s M51 ballistic missile launched from submarines.
The ministry says it offers greater range, precision and penetration capability and is equipped with new TNO-2 oceanic nuclear warheads.
The French Navy’s four Triomphant-class submarines are to carry 16 M51 missiles each.