Triomphant-class submarine

Triomphant-class submarine
Name	Triomphant class
Caption	The lead boat, Triomphant (S 616), underway.
Builders	DCNS (now Naval Group)
Operators	French Navy
Class before	Redoutable class
Class after	SNLE 3G (planned)
In commission	1997–present
Type	Ballistic missile submarine
Displacement	Surfaced: 12,640 tonnes, Submerged: 14,335 tonnes
Length	138 m (453 ft)
Beam	12.5 m (41 ft)
Draught	10.6 m (35 ft)
Propulsion	PWR K15 reactor, 150 MW; pump-jet; 2 diesel alternators
Speed	>25 knots (submerged)
Range	Unlimited except by food supplies
Endurance	70+ days
Complement	111 (15 officers, 96 enlisted)
Sensors	DMUX 80 sonar suite, DSUV 62 towed array, Racal (now Thales) DRUA 33 radar
Armament	16 × M45/M51 SLBM tubes, 4 × 533 mm (21 in) torpedo tubes for F21 torpedoes & Exocet anti-ship missiles

Contents

Development and design
Construction and service history
Specifications
Armament
Operational history
See also

Triomphant-class submarine. The Triomphant class forms the core of the French Navy's strategic nuclear deterrent, known as the Force de dissuasion. These ballistic missile submarines (SSBNs) are the successors to the Redoutable class and ensure the continuous at-sea presence of France's nuclear arsenal. Designed and built by DCNS (now Naval Group), the four submarines represent a significant advancement in stealth, detection, and firepower for the Marine Nationale.

Development and design

The development of the Triomphant class, initially designated SNLE-NG (Sous-marin Nucléaire Lanceur d'Engins de Nouvelle Génération), was authorized in the early 1980s to replace the aging Redoutable-class boats. The program aimed to counter advances in Soviet Navy anti-submarine warfare capabilities, particularly from vessels like the Akula-class submarine. Key design priorities included exceptional acoustic quieting, achieved through an advanced pump-jet propulsion system, sound-dampening raft mountings for machinery, and a hydrodynamically efficient hull form. The class integrates the SYCOBS combat system and is powered by a single K15 reactor, a compact pressurized water reactor also used on the ''Charles de Gaulle'' aircraft carrier. The submarines were designed from the outset to carry the new M45 missile and its planned successor, the M51 missile.

Construction and service history

Construction of the lead boat, Triomphant (S 616), began in June 1989 at the DCNS shipyard in Cherbourg. It was commissioned into the French Navy in 1997 following extensive sea trials. Three additional submarines followed: Téméraire (S 617) (commissioned 1999), Vigilant (S 618) (commissioned 2004), and Terrible (S 619) (commissioned 2010). The construction of Terrible experienced delays to allow for modifications to accommodate the larger M51 missile. Each boat undergoes a major refit and nuclear refueling (Grand Carénage) approximately every ten years, with these complex operations carried out at the Brest Arsenal. The class is based at the Île Longue strategic submarine base in Brest, part of the Atlantic Fleet.

Specifications

Each Triomphant-class submarine displaces 12,640 tonnes on the surface and 14,335 tonnes submerged, with a length of 138 meters and a beam of 12.5 meters. The K15 reactor provides primary propulsion, driving a pump-jet for high submerged speeds in excess of 25 knots. The electrical backup system consists of two SEMT Pielstick diesel alternators. The sensor suite is comprehensive, headed by the DMUX 80 multi-function passive/active sonar array, supplemented by a DSUV 62 towed array sonar and a Racal (now Thales) DRUA 33 surface-search radar. The crew complement is 111 sailors, including 15 officers.

Armament

The primary strategic armament is 16 vertical launch tubes for submarine-launched ballistic missiles (SLBMs). The boats initially entered service armed with the M45 missile, a three-stage thermonuclear weapon with a range of 6,000 km and multiple TN 75 warheads. From 2010 onward, they have been progressively refitted to carry the newer M51 missile, which has a range exceeding 10,000 km and carries the TNO warheads. For self-defense and tactical missions, the class is equipped with four 533mm torpedo tubes capable of launching the F21 heavyweight wire-guided torpedo and Exocet anti-ship missiles.

Operational history

The Triomphant class maintains France's continuous at-sea deterrent posture, with at least one submarine on patrol in the Atlantic Ocean or the Norwegian Sea at all times. The boats operate under the command of the French Oceanic Strategic Force (FOST). In February 2009, Triomphant (S 616) and the British HMS ''Vanguard'' collided submerged in the Atlantic Ocean, highlighting the stealth of both vessels. The class has participated in numerous national and NATO exercises, including operations with the ''Charles de Gaulle'' carrier strike group. In March 2020, Terrible successfully test-fired an M51.2 missile in the Bay of Biscay as part of the Dissentiment exercise, validating the weapon system's reliability.