French submarine Triomphant (S616)

The Triomphant is a strategic nuclear submarine of the French Navy; she is the lead boat of her class. She collided with a British nuclear submarine in 2009.

Construction and testing
The first sheet of Triomphant was cut at DCN Cherbourg in October 1986, and her engine was shipped to her from DCN Indret five years later. The reactor was built into the vessel in August 1991, with the fore and aft sections being welded on in January and April 1992 respectively. She was armed and given a commander in May 1992 and moved from the assembly site to the completion basin in July 1993. Her launch in March 1994 was followed by her first dive that June and her trip from DCN Cherbourg to lle Longue that July down the "free route" between Cherbourg and Brest, with a crew of 110 and engineers from DCN Cherbourg. On 4 January 1995, during testing, she reached her maximum depth for the first time and made her first firing of a ballistic missile the following month. Photographs of her were exhibited to the Senate of France from 15 to 23 May 1995. In June she set off back to Cherbourg for Post-Testing Upgrades (Remises A Niveau Après Essais or RANAE), then set off for a second set of trials, making 1,300 hours of test dives in total and a five-week trip. She then spent five weeks in maintenance at Cherbourg and during her main weapons tests took on 11 torpedo models, five trial torpedoes and one Exocet SM39 exercise. As a deterrent system, a salvo of 15 models was successfully launched and, in the last round of development, she functioned successfully as a missile platform even if her engine did not achieve its best. She left Cherbourg on 7 March 1996 for her second round of trials, with the final tests of her nuclear boiler coming on 12 July and of her weapons systems on 26 August.

Active service
Triomphant entered active service in March 1997. On 18 October 2001, the fleet support service notified the DCN that Triomphant was about to take her first period of Unavailability for Maintenance and Repairs (IPER or Indisponibilité pour Entretien et Réparations). The 150 million Euro contract was granted to DCN, with the IPER starting at Ile Longue on 2 April 2002, scheduled for 29 months in all. In this, her first major refit, her missiles and the fuel elements of her nuclear boiler were disembarked. In August 2004 L'Humanité ran a piece with the headline "Pas si Triomphant que ça" reporting that Triomphant had suffered a nuclear leak from one of her nuclear warheads by the end of 1997 and from her reactor in 2004, though the FOST downplayed the incidents and stated no radiation had been released since the reactor had been nonoperational at the time. She carried out a test flight of a M45 strategic missile on 1 February 2005 in the Atlantic. In the night between 3–4 February 2009, Triomphant collided with the Royal Navy submarine HMS Vanguard. Triomphant was reported to have proceeded to Brest under her own power, submerged, but with extensive damage to her sonar dome.

The French originally claimed that Triomphant had "collided with an immersed object (probably a container)". After Vanguard returned to harbour, it was confirmed that the collision was in fact with her.