Forward section of the former "Saphir" is being welded back to "Perle"‘s aft section in order to save the submarine.
French shipbuilder Naval Group received Florence Parly, Minister of the Armed Forces, and Admiral Pierre Vandier, Chief of Staff of the French Navy, at its Cherbourg site. They visited the yard where the Rubis-class nuclear-powered attack submarine (SSN) Perle is currently being repaired.
This event follows the decision taken on October 22, 2020 by Florence Parly, Minister of the Armed Forces, to proceed with the repair of the Perle. During the fire which lasted 13 hours, the high temperature altered the the quality of the submarine’ steel in the forward section of the hull. As a consequence, the forward section of Perle was cut off and the forward section of another Rubis-class SSN, the Saphir, is being welded back to Perle‘s aft section. The Rubis-class SSN Saphir, second boat of the class, was decommissioned in July 2019. Perle is the sixth and final boat of the class, it was commissioned in July 1993.
According to Naval Group, the “hybridisation” of 2 submarines is both an innovative and controlled operation:
- cutting of the two submarines
- movement and alignment of halves of the submarines
- welding of the thick hull
- splicing of hundreds of cables and manifolds
Main milestones for Perle’s repairs:
12 June 2020: Perle is damaged in a fire while in overhaul inside Toulon naval base:
10 December 2020: Perle leaves Toulon aboard semi-submersible vessel Rolldock Storm.
22 December 2020: Perle reaches Naval Group’s submarine shipyard in Cherbourg.
February 2021: Perle and Saphir are both cut in half:
March 2021: Preparation work for the junction of the two hulls sections:
April 2021: Wielding of the aft section of Perle with the forward section of Saphir.
Summer 2021: Undocking from the repair dry dock and start of overhaul work
Late 2021: Transit toward Toulon naval base to finish overhaul work
2023: Perle back in operational service:
Images courtesy of 800tonnes.com
1.4 meters longer, 68 tons heavier
Once repaired, Perle will feature an additional section and therefore will be longer by approximately one meter. This is because the two “half hulls” were not cut at the exact same spot, in order to easy the connections of internal equipment. The submarine’s displacement will increase by 68 tons. The additional section will bring the crew two new compartments aboard the submarine.
About Perle’s fire
For the record, on June 12, at 10:35 am, a fire broke out in the fore zone of the Rubis-class SSN Perle in a basin within the naval base of Toulon (South of France). The blaze was put out at 12:50 am the next day, after more than 14 hours of a fight that mobilized a hundred firefighters and more than 150 sailors in support.
Perle’s fire leaves a capability gap affecting the French submarine force as well as the security of the French nuclear deterrence. The French Navy is left with only 4 operational SSN. The next class of SSN, the first ship-in-class Suffren , which started sea trials this year, won’t be fully operational until 2021.
About French Navy Rubis-class SSN
According to Covert Shores’ World Submarines Recognition Guide, The first of the six Rubis-class submarines was commissioned in 1983 and the final one in 1993. They are the smallest nuclear-powered submarines in the world with a length of just 73.6 meters and a submerged displacement of 2,600 tons.
From the beginning, the boats were disapointingly noisy and failed to achieve some of the performance objectives (such as top speed). As a consequence, the French Navy and industry embarked on the Amethyste upgrade program in 1989. AMETHYSTE stand for Amélioration tactique, hydrodynamique, silence, transmission, écoute (Silent Acoustic Transmission Tactical Hydrodynamic Improvement). It brought a number of upgrades including a major change to the hull form and bow. By 1995, all six boats of the class had been upgraded.
Rubis-class submarine specifications
- Displacement: 2,400 tons surfaced; 2,670 tons submerged
- Length: 73.6 meters (241 feet)
- Beam: 7.6 meters (25 feet)
- Speed: 18 knots surfaced; 25+ knots submerged
- Depth: 300 meters (984 feet) operational
- Propulsion: K48 pressurized water reactor (64,000 hp); 2x turbo-alternators; 1x 9400 hp electric motor, one shaft
- Complement: 75 sailors (dual crew system: Blue and Red crews)
- Weapon systems: 4x 533mm torpedo tubes for 14x F17 torpedo or 14x Exocet SM39 anti-ship missiles
- Sensor systems: DMUX-20 active/passive sonar; DSUV-62C towed array