France’s DGA Confirm the M51.3 Ballistic Missile Has Entered Operational Service
The French Defense Procurement Agency (DGA) confirmed on 28 October, that the M51.3 submarine-launched ballistic missile (SLBM) has entered operational service. This formal entry was signed off on 24 October by French Armed Forces Minister Catherine Vautrin. Developed under DGA supervision by prime contractor ArianeGroup, the M51.3 will gradually replace the older M51.1 and M51.2 missiles aboard France’s four Triomphant-class nuclear ballistic missile submarines.
The M51.3’s upgrades include extended range and improved payload. Its solid-fuel three-stage design is reported to reach roughly 9,500–10,000 km and it carries multiple independently-targetable re-entry vehicles (MIRVs). Each M51.3 missile is armed with France’s new Tête Nucléaire Océanique (TNO-2) warheads which will replace the older TN75 warheads. These modern 100–150 kiloton warheads are maneuverable and increase survivability against missile defenses. The M51.3 offers improved guidance and accuracy compared to earlier M51 models and helps it penetrate advanced enemy missile defenses.
To certify the M51.3’s performance, France carried out a qualification test in November 2023 from its Biscarrosse missile test center. This followed an extensive flight test program for the M51 series: the first full-scale M51 launch in 2006 succeeded, one launch in 2013 failed, and later trials in 2015, 2016, 2020, 2021 and April 2023 all succeeded. The November 2023 firing was the inaugural launch of the M51.3 variant, validating its design before deployment.
As France’s primary sea-based weapon, the M51.3 underpins the country’s nuclear deterrent (Force de dissuasion). The Triomphant-class SSBN fleet – four submarines each carrying up to 16 missiles – maintains a continuous-at-sea alert posture, and officials say M51.3 “reinforces the credibility of the oceanic component” of France’s deterrent against evolving threats. France also stresses its strategic autonomy: its nuclear forces remain under national command (outside NATO’s operational chain of command).
France’s defense industry led the M51.3 program. ArianeGroup, Europe’s strategic missile prime contractor, managed the design and production effort. The French Atomic Energy Commission (CEA) developed the TNO-2 warhead under its national simulation program. The M51.3’s entry into service underscores France’s commitment to a modern nuclear deterrent.