The nuclear attack submarine Suffren, the future arm of the French Navy, begins its sea trials

We have mentioned it in recent days: the renewal of French attack submarines is on the right track. On the one hand, the Suffren, first in a new class of nuclear attack submarines, now floats freely and is currently starting its sea trials. On the other hand, the French Navy received its first new generation heavy torpedoes, which will constitute the main armament of these new buildings.

Together, the Suffren class and the F21 torpedo will allow the replacement of the Rubis nuclear submarine class and the F17 torpedoes, now obsolete in many respects. The opportunity for us to return to the Barracuda program which led to the creation of this new Suffren class.

The Suffren during its official launching ceremony on July 12, 2019. Since then, the building has experienced a refueling of nuclear fuel, a launch, the divergence of the reactor core and its first buoyancy tests.

Historical overview of the Barracuda program

Since the commissioning of the first nuclear missile launchers (SNLE) in the 1970s, France has implemented an industrial policy aimed at maintaining the know-how necessary for the design and construction of nuclear submarines, essential to deterrence. To maintain skills over time, it is decided to order a class of nuclear attack submarines (SNA) between each class of SSBN.

Thus, after six SNLE class Le Redoutable, France launched six SNA Ruby class, which entered service between 1983 and 1993. Four SNLE class Le Triomphant were then launched between 1994 and 2008, and the program of six SNA Barracuda was to take over to replace the six Rubies in the early 2010s.

In 2007, shortly before the Suffren was put on hold, the general lines of the building were already frozen. However, we note that the length and displacement of the submarine have since been revised upwards.

However, between the budget cuts of the 2000s, conceptual hesitations and attempts at European rapprochement, the program ended up falling considerably behind. In 1998, the Barracuda (also called SMAF, for future attack submarine) was to be an SNA of 4000t in diving, and its entry into service was expected for 2007, or 2010 at the latest. In 2004, the building had grown to 4600t and a delivery date in 2012. The calendar and technical specifications gradually shifted to stabilize around a delivery by 2020 and a design of 99,5m long for 5400t of diving trip.

It should be noted, however, not without irony, that a rapprochement was mentioned with the United Kingdom in the late 1990s, around a much heavier submarine optimized for anti-submarine warfare. However, the British did not anticipate commissioning until 2015, where the replacement of the Rubies was to be completed no later than 2013. In the end, the first British Astute, an SNA over 7800t, entered service … 2010, while Suffren will not be operational before the end of 2020 the best. We will console ourselves, however, by remembering that the unit cost of the Barracuda is much lower (35 to 50%) than that of the Astute, that the design of the Suffren is better adapted to the needs of the French Navy (especially for developments in shallow waters ), and that the Barracuda program has been much more profitable for the French national industry than a collaboration on board an essentially British program.

Astute class nuclear attack submarine. With a displacement of nearly 8000t, around forty weapons in the hold and a speed of more than 30 knots, British submarines are more optimized for hunting submarines in the North Atlantic than for protection missions and intelligence carried out by the French ANS.

Le Suffren in a few figures

The Suffren is the first representative of six Barracuda-type buildings (Suffren, Duguay-Trouin, Tourville, De Grasse, Rubis and Casabianca) to be delivered before the end of the decade. 99,44m long, it displaces 4700t on the surface and 5300t in diving. Its maximum speed exceeds 25 knots, and its immersion depth is officially "greater than 350m", indicating that it probably exceeds the 400m (in peacetime) sometimes indicated at the launch of the program. The autonomy in living, 45 days on Rubies, should be able to exceed 70 days on the Suffren class.

The diameter of 8,8m of the hull is imposed by the size of the nuclear reactor, derived from the K15 of SNLE Le Triomphant. Unlike what can be done in the US Navy, for example, the fuel for K15 reactors is the same as that found in civil power plants, which reduces costs and improves job security and safety. 'supply, but requires recharging every 10 years.

Suffren in assembly. Suffren is also 20km of pipes, 160km of cables and above all 21 million lines of code! With the exception of a few spacecraft, a modern nuclear submarine is arguably the most complex object in the world.

Very automated, the Barracuda should be used by 65 men and women, a little less than on board Rubies, however, more than twice as small. From the design stage, it was planned to be able to carry around fifteen specialists, in particular commandos who could operate from a dedicated airlock but also from one of the two Removable Dry Dock Shelter designed by Naval Group for French Suffren. Can be placed on the back of the submarine, this equipment of 15m long and 43t allows to embark the equipment of the commandos.

The implementation of special forces specialists was taken into account in the design of the submarine, not only by the reserves of internal volume dedicated to the commandos, but also by the general design of the building, in particular its rear diving bars in X, much more practical to navigate in shallow water or against the bottom.

The submarine's combat system is the SYCOBS of Naval Group recently integrated into SNLE, facilitating the transfer of human resources between SNA and SNLE. The SYCOBS centralize information from the Thales UMS-3000 bow sonar coupled with two sidewall antennas and, in the coming years, a towed sonar train. The Suffren also implements several non-penetrating optronic and electronic masts produced by Safran, replacing the traditional periscopes. Enough to offer him an optical, infrared, radar and electronic watch capacity at 360 ° day and night.

What weapons for the Suffren class?

Unlike SNLEs, SNAs do not carry nuclear missiles but conventional torpedoes and missiles. In France, their primary role is the anti-ship fight followed by the anti-submarine fight, in order to protect the main units of the French Navy: SNLE, aircraft carriers, amphibious groups. Like all submarines, SNAs are also excellent stealth platforms for wiretapping or commando drop missions, as we have already seen. In recent years, the attack capabilities of attack submarines to shore have grown considerably around the world, and France is no exception. This is felt on the configuration of the ship's arming.

The F21 heavy torpedo is the most modern and undoubtedly the most efficient in its class. The first units have recently been delivered to the French Navy and to Brazil. It is also available in India (around 36 copies) and in Greece (around XNUMX units)
  • The heavy torpedo F21, which we have described in detail lately, will be the basic weapon of the Barracuda type, and one of the most modern and efficient torpedoes on the market. With a wire-guided range of 50km (and a priori higher in autoguiding), a maximum speed of 50 knots and an operational depth exceeding 1000m, it will be able to destroy any submarine and most of the large surface units in a knock.
  • The SM-39 Exocet anti-ship missile is a complementary weapon to the F21. If it does not offer the persistence and destructive power of a heavy torpedo and does not strike at a longer distance, the Exocet can still reach its target considerably faster. In addition, Exocet and F21 can act in a complementary manner depending on the defensive capabilities of their target, depending on whether it has above all anti-aircraft or anti-submarine armament.
  • The MdCN (Naval Cruise Missile), formerly called Scalp Naval, is an action missile towards the earth with a range greater than 1000km, capable of hitting high value hardened targets with extreme precision. Already operational on the FREMM frigates, the MdCN will offer French SNAs tenfold operational capacity. Like the Exocet, the MdCN are fired like torpedoes from waterproof containers.
  • The Suffren class should be able embark on new generation mines, intended to replace the old FG29 fitted to the Rubies today. Particularly sensitive, this naval interdiction weapon is undoubtedly one of the best kept secrets of the French Navy. A priori, the new mines should be smarter, more versatile and have greater autonomy than the FG29.
  • Finally, in the future, the submarines of the Barracuda program will be able to implement new equipment. It could be different types of underwater drones, potentially based on the Naval Group's D19, suitable for operations reconnaissance, demining or electronic intelligence. Drones aerial or even anti-aircraft missiles (MICA or MICA-NG type) could also be integrated into watertight containers.
Naval Group is not stingy with proposals for the equipment of its submarines. In 2013, the group partnered with MBDA to offer a launch solution for MICA and Mistral anti-aircraft missiles. The option remains offered, even if it has not yet been funded.

To implement this range, the Suffren has four 533mm tubes. Typical choice of French submarines, the implementation of weapons is carried out by means of a pneumatic repressor. The latter is much more discreet than direct flushing with compressed air, but slightly noisier than an engine starter switched on from the tube. However, for reasons of nuclear safety, the French Navy never starts the ignition of the torpedo propulsion in the tube. The other advantage of the repressor is to facilitate the firing of torpedoes and missiles at great depths and at relatively high speeds (especially for torpedoes).

Unfortunately, if the option seems to have been studied at the start of the SMAF / Barracuda program, then regularly mentioned without real materialization, the Suffren class will not include vertical launch tubes (VLS) for its cruise missiles or its anti-ship missiles. Technically, such an option would no doubt have been feasible, Naval Group also offering it on its SMX Ocean design derived from Barracuda. However, beyond the costs inherent in such a system, the question of security has undoubtedly cooled the ardor of the French Navy on this subject, since the most likely location for a VLS module would have been just at the front of the reactor compartment.

In the end, the Barracuda will only carry 24 weapons: 20 in the hold and 4 in tubes, in torpedo / missile / mine proportions that are currently unknown. If the size of the hold is doubled compared to that of the Rubies, it remains relatively small compared to other submarines of smaller tonnage. However, it would seem that the volume of the torpedo compartment is sufficient for loading additional ammunition, provided that the system is modified to allow greater density of storage. What offer some leeway for the future development of buildings.

Barracuda for export

The Suffren is the first vessel of a new class of SNA which will take its name from the French Navy. Nevertheless, the name of the program from which it comes is BARRACUDA which, strangely, does not seem to be an acronym unlike FREMM, FDI or SCORPION. Barracuda is also the trade name used by the designer and manufacturer of the ship, Naval Group, both on the French and international market.

The fairing propeller (pump-jet) is one of the strong points of the Barracuda design. She will be on the Australian Attack class, but could also be offered by Naval Group for future Dutch and Indian submarines.

Indeed, if France has committed not to export military nuclear technologies, the gigantic expertise of Naval Group in the field of conventional and nuclear submarines has enabled its engineers to develop a conventional propulsion variant of the Barracuda. And even, technically, a whole family of conventional submarines based on the French Barracuda, and some versions of which have been exhibited in concept-ship forms like the SMX 3.0 or the SMX Ocean.

Designing its ships and submarines in a modular way, Naval Group offers a high degree of customization to its customers. This also concerns the propulsion of submarines, which can differ depending on usage and operational needs. For high speed over long distances, Naval Group will offer a large volume of conventional or new generation (Li-ion) batteries, rechargeable by diesel engines for example. For long diving patrols, but at reduced speed, Naval Group will offer its second generation AIP module.

So, the twelve Shortfin Barracuda sold to Australia should be equipped only with conventional batteries and not with AIP (even if at least part of the buildings could be equipped with li-ion batteries in the end), Australia wishes to favor speed over diving time. The model proposed in the Netherlands, initially inspired by the SMX Ocean, could include a mix of batteries and AIP, allowing submarines to quickly reach their area of ​​operation in the Caribbean, for example, where they can then navigate at low speed under AIP.

The Riachuelo, the first Scorpene launched in Brazil. For the moment, no Scorpene has been equipped with AIP propulsion, even if the option exists and is integrated on the Pakistani Agosta-90B. Today, Naval Group offers a second generation solution based on the reforming of diesel oil and ensuring 18 days of underwater autonomy.

Naval Group's possible future export success should however help to clarify the range offered by the manufacturer. For the moment, it revolves around the Scorpene of around 2000t and the Barracuda / Shortfin Barracuda of around 5000t. Models offered in the Netherlands and in India seem to take over the hull diameter, the arrangement of the sensors and the Barracuda propellant, but their displacement in diving should be around 3500t. Will they then constitute an intermediate range in the catalog of Naval Group? Or will they be the basis of the high industrial offer, the Australian Shortfin Barracuda then remaining an exception linked to the unique geography of this country?


Anyway, the dynamism of Naval Group in the export of submarines is undoubtedly exemplary in Europe. Today, the French manufacturer is still neck and neck with the German TKMS, which builds on the success of its Type 209 to offer the new Type 214 for export. But Naval Group, with the high level of requirement of French nuclear submarine programs, is now able to offer a full range of high performance submarines proven at sea.

Better yet, the French group offers these submarines at a particularly impressive price / quality ratio, especially since the company does not hesitate to carry out complete transfers of technology and know-how, as we have been able to see in India and Australia. What promise still great export success in the coming decades.

Also read

You can not copy content of this page