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The six Rubis submarines are the smallest impact nuclear submarines in the world. They are armed with four torpedo tubes, also suitable for firing Exoset cruise missiles. This “nuclear powered Agosta” was initially known as the SNA 72 class, then class Provence (the two following vessels being called Brittany and Burgundy), before being renamed under the presidency of Valéry Giscard d'Estaing.

France has a long history of building and operating submarines. Contrary to other countries which first of all developed nuclear powered attack submarines, the first efforts of France were directed into the building of a ballistic missile submarine. The French began gradually turning to ballistic missile submarines ("sous-marins nucléaires lanceurs d'engins", or SNLE) - with production beginning in 1964 and Le Redoutable becoming operational in 1972 - and, later, nuclear attack submarines ("sous-marins nucléaires d'attaque", or SNA), the first of which, Le Rubis, became operational in 1981. The first class of French nuclear powered attack submarines was equipped with second generation reactors.

Despite the high cost of reactor development and production, as soon as the nuclear-powered submarine appeared in the mid-1950s, navies from around the world struggled to secure nuclear-powered submarines. In the 1950s, the French Navy launched its own nuclear-powered attack submarine (SSN) project. When Charles de Gaulle took office in France in June 1958, he declared his own military route and pursued the expansion of strategic weapons. Accordingly, all resources were put into securing 3-axis strategic weapons (strategic missiles, strategic submarines, and strategic bombers), and the French Navy also preferentially promoted the development of nuclear-powered strategic submarines equipped with ballistic missiles.

The French Navy decided that it was difficult to develop a completely new attack submarine because the replacement of the old diesel engine attack submarine was urgent and the budget was insufficient. Therefore, the ruby-type attack submarine project started in 1974, where the hull and combat system utilize the existing Agosta-class diesel attack submarine (underwater drainage 2,000 tons) as it is, and only the propulsion engine is changed to nuclear power.

The first Rubis-class submarine was laid down in 1976 with torpedo and sonar systems inherited from the diesel-electric Agosta class. The first of the French SNA (Sous-marins nucléaires d'attaque - Nuclear Attack Submarine) Rubis class nuclear submarine was launched in 1988. The Rubis was an elegant design that overcame many of the faults with other nuclear submarines. With a displacement of 2,400 tons they are the most compact nuclear attack submarines to date - not significantly larger than a Scorpène-class conventional boat of up to 2,000 tons. The British Valiant, Swiftsure, and Trafalgar classes of the 1960s, '70s, and '80s displaced between 4,000 and 4,500 tons at the surface and were about 285 feet long.

In 1987, the Canadian White Paper on Defence recommended the acqusition of 10 to 12 Rubis or Trafalgar-class submarines, to be known as the Canada-class. with the choice of the type of submarine to be confirmed before Summer 1988. Canada's goal was to build a three-ocean navy and to assert Canadian sovereignty over Arctic waters. The Rubis-class failed to meet the Canadian Statement of Requirement (SOR). being noisy underwater and slow realtive t the Canadian requirements. It also came with the requirement that the first 4-5 submarines would have to be built in France.

The Canadian Navy, which demanded the ability to conduct operations in the Arctic Ocean, where Soviet submarines were predominantly active, chose French ruby-class submarines. However, along with protests from the British government, technical shortcomings became a problem, and eventually the introduction plan was discontinued in April 1989.

By the early 1990s the French fleet includes five nuclear ballistic submarines (Le Redoutable and L'Inflexible classes), with two more under construction (Le Triomphant class), six nuclear attack boats (Rubis class), and several older diesel attack submarines (Agosta and Daphne classes). The overhaul of the two SSBNs and the continued construction of the Rubisclass attack submarines helped lessen the negative impact of low production when the new class of SSBNs was started. This sea-based capability, by extending the reach of France's deterrent and improving its survivability, was designed to bolster its credibility.

Budget reductions resulted in the cancellation of two Rubis-class attack submarines and a reduction in the number of new SSBNs from the original six to the current four. The seventh boat in the Rubis class, the Turquoise, was halted after the pressure hull and reactor components were completed; this boat is in storage. The eighth boat, the Diamant, was canceled.

The 5th unit, S605 Améthyste, is an upgraded version. Améthyste is not only the name of a gemstone, it's an retronym for "AMElioration Tactique, HYdrondynamique, Silence, Transmissions, Ecoute"(Tactical, hydronynamical, Silent, Transmissions and Sensors Improvement). This version is fitted with a linear towed array working on low frequencies. Automation of some tasks are also part of the improvements.

Rubis-class submarines are powered by two turbo alternators; one main motor (with an emergency electric motor); one CAS 48 pressurised water-cooled nuclear reactor rated at 48 MW; one Jeumont-Schneider auxiliary diesel electric motor, providing a top speed of 25 knots. The Rubis-class submarines 48 MW reactor needs no refuelling for 30 years. Armament consists of Aerospatiale SM 39 Exocet anti-ship missiles launched from four 533 mm torpedo tubes; ECAN L5 Mod 3 dual purpose torpedoes; or up to 32 FG 29 mines carried in lieu of torpedoes.

The Rubis-class attackers adopted a nuclear turbine electric propulsion method that makes the most of the existing hull. This method is a method of generating electricity by rotating the generator with high-pressure steam generated by operating the boiler with nuclear power. The electricity generated is rotated to propel the electric motor again, and this method was developed as a concept that replaced only the diesel engine with the nuclear reactor in the existing diesel electric propulsion submarine. The French Navy's unique nuclear turbine electric propulsion method has the advantage of low noise during voyage, but it is not used by other navies because of its complexity, weight, and reliability. However, the French Navy is applying its own unique technology to all nuclear-powered submarines. The nuclear reactor, which is the core of the nuclear propulsion engine, uses pressurized water reactors.

French SNA were designed to be able to sail for 220 days a year. Two alternating crews each of 68 personnel provide the ships compliment. In order to achived a sufficient operational availability given the reduced number of submarines at disposal, the SNAs are manned by two crews which rotate according to operational and maintenance cycles as well as, for crews, according to to deployements, training and leaves.

The initial design of the Rubis proved to be problematic with unexpectedly high noise levels. This led to the AMÉTHYSTE silencing program (AMÉlioration Tactique HYdrodynamique Silence Transmission Ecoute, a retronym literally meaning Silent Acoustic Transmission Tactical Hydrodynamic Improvement) which was applied to the fifth (S605 Améthyste) and sixth (S606 Perle) hulls. Améthyste and Perle were both longer that the original Rubis, 73.6 meters (241 ft) as compared with 72 meters (236 ft) and the program included upgrades to the sonar, reshaping of the hull form and bow to improve silencing and additional upgrades of the electronics.

Beginning in 1984, new and existing vessels of this class were given improved sonar and silencing and were fitted with dive-launched Exocet antiship missiles. The first batch of Rubis class submarines was initially equipped for an anti-surface role, but since becoming the Rubis-Améthyste class they also perform anti-submarine warfare functions.

"Amethyst" became 1.5 meters longer than its predecessors, received a modified nose, which housed a spherical antenna of the sonar station, a towed antenna. The cabin has become more streamlined, the use of soundproofing materials has become much wider, the electronics of the boat has been updated compared to its predecessors.

With the upgrades tested and proven, the original 4 boats were rebuilt to the same standards between 1989 and 1995. As of 2006, all but the first Rubis-class had undergone modernization to the "Améthyste" standard with their military capability expandded in the areas of underwater detection, communications and acoustic discretion.

DUUX-5 Fenelon was developed to provide Rubis class submarines with panoramic search, passive acoustic rangefinding and panoramic sonar interception capability. The DUUX-5 Fenelon is an upgrade of the DUUX-2. It passively detects submarines at long ranges, making an active system necessary only for fire control. A set of six flat array panels are fitted three per side. Using at least two units per side, the submarine can determine a contact's range by triangulation. Course and speed can be determined by TMA (Target Motion Analysis). The system is deployed on Rubis and Amethyste class SSNs, L'Inflexible and Le Redoutable class SSBNs, Spanish Agosta class SSKs and, according to some reports, Chinese Project 091 Han class SSNs, the Project 039 Song class and the Project 035 Ming class SSKs. Estimation of the unit cost of DUUX-5 is difficult since it usually forms an integrated part of a sonar suite. However, comparison with the known costs of similar systems indicates an approximate unit price of US$2 million. A sonar intercept unit records the bearing of all transmissions heard in the 2 kHz to 15 kHz band. It monitors noise near the submarine in 120-degree sectors on each side of the submarine. Four contacts can be tracked at once, one per 120-degree sector (on radiated self-noise) and one by the intercept unit (on sonar pulses).

Rubis was originally slated to begin being replaced, starting in 2010, by the first of a new class of submarines called "Barracuda". As of 1988 a "Post-Rubis" program anticipated the construction of at least three [later six] nuclear attack submarines which were supposed to receive - compared to the Rubis-class - a much-improved hull design and to be equipped with two reactors, instead of the previous single reactor. The launch of the program meant to replace six Rubis class nuclear submarines was delayed several times.

DCNS obtained a contract for providing through life support (TLS) until 2020 to the six nuclear attack submarines in service in the French National Navy and based in Toulon. This contract confirmed DCNS leadership in through life support. The contract was notified by the Fleet Support Department and became effective on 01 April 2015.

The contract covers the provision of through life support to the entire fleet of nuclear attack submarines, which comprises six Rubis-type ships as well as preliminary servicing for Suffren, the First of Class of the Barracuda submarines. The contract also includes the operation of Toulon’s nuclear infrastructures, the tools as well as the simulators of the National school of submariners. Lastly, it covers the maintenance of infrastructures dedicated to the complete servicing of Rubis-type nuclear attack submarines, and the future installations in the process of adaptation for the routine servicing of the first Barracuda nuclear attack submarines that will be commissioned progressively from 2018 onwards.

On 10 June 2009 the Emeraude, a Rubis-class French nuclear submarine with advanced sonar equipment, began searching for the flight recorders of an Air France airliner that crashed into the Atlantic the previous week. The Emeraude was sent to the area to hunt the "black box" recorders, which may help explain the disaster and which are believed to lie on the ocean floor.

During the NATO Navy exercises in 2015, the Rubis-class submarine Saphir was able to get close to the U.S. aircraft carrier Theodore Roosevelt and conditionally destroy it. Both the French Defense Ministry and the Navy released and then quickly deleted a news post entitled “Le SNA Saphir en entraînement avec l’US Navy au large de la Floride” (“The SNA Sapphire in training with the US Navy off the coast of Florida”) that praised the 34-year-old French nuclear submarine’s success in “sinking” the American aircraft carrier USS Theodore Roosevelt along with best part of its escort.

The French sub snuck up undetected on US Carrier Strike Group 12 by penetrating a US defensive screen. “The Saphir has quietly slipped into the heart of the screen formed by the American frigates protecting the aircraft carrier, while avoiding detection against-pervasive air assets ,” the original release read as quoted by French Challenges blog. “On the morning of the last day, the order of fire was finally given, allowing the Saphir to fictitiously sink Theodore Roosevelt and most of its escort.” No other details are available about the outcome of the exercise.

The French Navy S606 Perleatomic submarine survived the fire in the dry dock of Toulon's naval base. The submarine has been there since January. The fire on board the 73-meter ship occurred on the morning of June 12. There were no nuclear fuel and weapons on board, and they were removed before maintenance. All personnel have been evacuated safely. The local government said that with the help of professional teams and fire ships transported from Marseille, dozens of firemen responded to the fire at the scene. According to Reuters news, as of the afternoon of that day, the fire was still spreading. The fire was extinguished only at 17 o’clock. Judging by the photo, the submarine is seriously damaged by fire. Sheathing of the nasal tip of composite materials - under it is the sonar antenna - is completely destroyed. The French Ministry of Defense reported that there were no injuries, and the products of combustion released into the atmosphere are not radioactive.

The French Navy operated one or two carrier-operated fleets, with six submarine squadrons of ruby-class assault ships being put into operation. The submarine crew is organized into two groups, shifting work every three months. The ruby-class submarine that has been active for a long time would become obsolete and would be replaced by a Barracuda-class submarine from 2018, with all ships decommissioned in 2026.

The nuclear attack submarine (SNA) Perle left the Toulon naval base 10 December 2020, to be transported to Cherbourg-en-Cotentin, aboard the specialized semi-submersible charter ship Roll Dock Storm. This large-scale operation was the first step in the repair process for the SNA Perle, after the fire suffered on 12 June 2020, in dry dock in Toulon, while it was on Periodic Unavailability for Maintenance and Repair (IPER). Organized in coordination by the French Navy and the Fleet Support Service on the one hand, and the industrial Naval Group on the other hand, the transfer and repair of the Perle SNA will make it possible to maintain the operational capacity of the Strategic Oceanic Force. (FOST) at its best. This transfer followed the decision taken on October 22, 2020 by Florence Parly, Minister of the Armed Forces, to repair the SNA Perle. The front part of the submarine having been damaged by the fire, the solution adopted will consist in replacing it with that of the SNA Saphir, withdrawn from active service in the summer of 2019. This repair will make it possible to maintain the format of the sub fleetof nuclear attack vessels.

The transfer of the SNA Perle from Toulon to Cherbourg-en-Cotentin is necessary because only the latter's infrastructures allow this large-scale work to be carried out. “The embarkation of the SNA Perle aboard the Storm and its departure for Cherbourg symbolically mark the beginning of the reconquest of the Pearl. After repair, the submarine will have regained its technical potential and will be fully operational until the date scheduled for its withdrawal from active service, the Ruby type ANSs being gradually replaced by the Suffren type ANSs, while maintaining the format of the six-submarine ANS fleet ” explains General Engineer Guillaume de Garidel, central director of the fleet support service. The cutting, hull welding and connection work will be carried out in Cherbourg-en-Cotentin. They will be followed by a return to Toulon where the submarine will resume the IPER interrupted in June.

This repair, although exceptional, is a controlled industrial operation. Operations of this kind have in fact already been carried out on submarine hulls, in France and abroad. It will be carried out while respecting all the conditions necessary for the safety and operational capacity of the submarine. The Minister's decision to repair the Pearl will allow the French Navy to retain its full nuclear attack submarine capacity for the next ten years: "Repairing the Pearl," specifies Florence Parly, is not only about a remarkable industrial operation. It is first and foremost to preserve the independence of France and assert our sovereignty”.

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Page last modified: 05-05-2021 19:35:03 ZULU