The French Navy has received its ballistic missile submarine (SSBN), Le Triomphant, after the completion of modernisation works.
The transfer of the submarines' responsibility to the navy marks a significant milestone in its availability for maintenance and repairs (IPER).
The vessel was also equipped with the M51 strategic missile during the overhaul programme.
During the 20-month modernisation period in drydock 8 at Brest, Le Triomphant's missile launch tubes were replaced to accommodate the new-generation M-51.
In addition, the submarine was installed with the SYCOBS tactical combat system along with SGN-3E global navigation system.
The vessel has now returned to French Navy's nuclear submarine base near Brest and will begin testing before returning to service.
Le Triomphant represents the second SSBN modified for the M51 during an 'adaptation' IPER. Another Triomphant-class SSBN, the Vigilant, benefitted from similar transformation between 2010 and 2013.
Meanwhile, France's next SSBN, Le Téméraire, is set to undergo a major upgrade in 2016.
The fourth Triomphant-class vessel, which was commissioned in 2010, received similar upgrades during the time of construction.
The French Navy developed the Triomphant-class submarines to replace the L'Inflexible M4 class SSBNs.
The submarines have four 533mm torpedo tubes and feature the capacity to carry a mixed load of 18 ECAN L5 mod 3 torpedoes and Exocet missiles.
In addition, it has a submerged speed in excess of 25k and a surface speed of 20k. The diving depth is more than 300m with more than 60 days of endurance.
Image: The French Navy's ballistic missile submarine (SSBN), the Vigilant. Photo: courtesy of Marine nationale.