TheS-80 Plus class (orIsaac Peral class) is a Spanish class of four submarines being built by the state-owned[10] Spanish companyNavantia at itsCartagena shipyard for theSpanish Navy. In common with other contemporary submarines, they featureair-independent propulsion.
The class has its roots in the late 1990s, and Spain ordered the submarines into production in 2003. Due to problems with the design, it had to be extensively redesigned in the 2010s, and aSpanish government budget crisis forced additional delays. On November 30, 2023, the first submarine of the class entered service with the Spanish Navy.
They are oceanic submarines of medium tonnage with the capacity to carry out long duration missions in scenarios far from their base, and to do so stealthily. They will have an integrated platform control system that allows operation with a reduced crew complement and a high degree of automation with remote control. The characteristics of this class of ships place them at a level close to those of nuclear propulsion.[citation needed]
Thelead boat in the class, theIsaac Peral [es], the first unit in the series, was launched by KingFelipe VI and his daughter,Princess Leonor, heir to the throne, on 22 April 2021 at the Cartagena shipyards, entered to service in 2023, after originally being targeted for 2011. In 2024, the delivery date for the second vessel had slipped to 2025.[11] The remaining three boats are slated to be delivered in 2026 and 2028. However, the second boat had later been delayed until 2026 with the third and fourth vessels of the class planned for service entry in 2028 and 2029, respectively.[12]The S-80 class has also been offered for export.
In the 1980s, France began studies for the replacement of theirS-60Daphné-class diesel submarines. The French shipyard DCNI (Direction des Constructions Navales International) came up with an all-new design called S-80, with ateardrop hull and new weapons and sensors, which the French government ultimately decided[when?] not to fund.[13] DCNI then proposed a cheaper option called the S-90B, anS-70Agosta-class submarine with limited improvements, which was rejected by the French but exported to Pakistan.[13] As the Spanish Navy faced the same problem in replacing theirDaphnés, known as theDelfín class in Spanish service. As part of Plan ALTAMAR, the firm Bazán (later Izar, and then subsequently, the Spanish state-ownedNavantia[10]) started on a new design. It was later agreed to collaborate in a joint venture[clarification needed] based on the French S-80.[13] This joint design was shown atEuronaval [fr] in October 1990.[13]
The end of the Cold War meant that funding dried up and the joint venture had to wait until 1997 for their first sale of the new design to Chile,[14] which was designated theScorpène class in export markets. The same year Spain started to look again at its requirements, and in 1998 they indicated that they would buy fourScorpènes,[13] optionally with an air-independent propulsion (AIP) system for greater endurance when submerged. A staff requirement for the S-80Scorpène variant was completed in October 2001.[15] This was soon overtaken by events, as the Armada (Spanish Navy) became more interested in using submarines forpower projection than static defensive role.[15] This shift was codified in guidance of January 2002 from the Chief of Naval Operations and in a strategic defence review in February 2003.[15] The new requirement called for a larger submarine with better endurance and land-attack missiles, which became known as the S-80A design. This was an AIP submarine with a hull diameter of 7.3 metres (23 ft 11 in), compared to 6.2 metres (20 ft 4 in) for theScorpène family, a submerged displacement of around 2,990 tonnes versus 1,740 tonnes, larger rudder surfaces and a different fin position.[15]
The Spanish government approved the purchase of four S-80A submarines in September 2003 and signed a contract with Izar on 24 March 2004.[16] The original deal was €1,756M to design and build four submarines,[16] about €439M per boat. However, this had increased to €2,212M[17] by 2010 (€553M per boat). The plan envisaged the first boat to be delivered in 2011 but government dithering over the company supplying the combat system pushed it back to 2013.[15] In 2011, Spain's budget crisis further delayed the first delivery until 2015, with the remaining boats being delivered at one year intervals until 2018.[18] Construction of S-81 began on 13 December 2007.[19] In January 2012 the names were announced, honouring three engineers who made submarines and the first commander of Spain's submarine force respectively -Isaac Peral (S-81),Narciso Monturiol (S-82),[20]Cosme García (S-83) and Mateo García de los Reyes (S-84).[21]
By May 2013, with overUS$680 million of the project's US$3 billion budget for the four submarines spent, an overweight issue was discovered and eventually made public. Navantia engineers had miscalculated the weight of the submarines by some 100 t (98 long tons; 110 short tons) of the total 2,000 tonne mass of the submarines, more than enough to sink the submarines if not fixed.[22]As of 2013[update] Navantia announced the issue would delay the delivery of the first submarine to the Spanish Navy until at least 2017.[23] That date proved to be optimistic. Lengthening the submarine created additionalbuoyancy.[10] Navantia signed on the US companyGeneral Dynamics Electric Boat to help solve the excess weight design issue.[24]In September 2014, the overweight issue was reported to have been resolved in design changes and the construction work to be ready to resume in late October 2014.[25][clarification needed]In November 2014, Navantia again reported having completed the redesign work to address the problem of overweight. In all, the hull would be lengthened by 10 metres (33 ft), and the displacement increased by 100 tons. As of January 2018[update], the intended delivery date of the first submarine was to be September 2022,[26] but this was not achieved. At the time of the boat's launch in 2021 it was indicated that the plan was for the first boat to start sea trials in 2022 and be delivered in 2023.[27]Isaac Peral started sea trials in mid-2022,[28] and completed its first static dive in March 2023.[29]
In January 2017, it was reported that the air-independent propulsion system would not be ready in time for the delivery of the first submarine.[30]In November 2018 Abengoa and Tecnicas Reunidas companies stated that the test for a new-type AIP engine of the submarine were successful.[31]TheIndian Navy considered the S-80 for its next generation of submarines underProject-75 class- submarine.[32] On November 30, 2023, the first unit of the class, the S-81, entered service with the Spanish Navy.[33]The Spanish government claims that S-81 is ready to join international exercises and S-82 will float in July 2025, though a strike led by theCSIF union could delay it.The workers complain about lower salaries than in other Navantia workplaces.[34]
By 2025, the maintenance costs are predicted to be over 102 million euros, leaving the unit cost near 1 billion euros, a cost closer to that of nuclear submarines than to equivalent units.[34]Out of 2,127 companies involved in the project, around 850 are Spanish.The funding however does not necessarily end mainly abroad.[34]
The Integrated Combat System Core (ICSC) is called VC 9.0 SCA.[35] The ICSC provides set of weapons and sensors of the combat system with an optimal management of the command and control center, allowing to acquire, evaluate and present all the necessary information for the offensive, defensive or intelligence gathering actions at each moment.[citation needed] The ship is fitted with active and passive sonars with accurate electromagnetic detection systems. The submarine can communicate via Link-11 and Link-22 data links.[35]
The S-80'sair-independent propulsion (AIP) system is based on abioethanol-processor consisting of a reaction chamber and several intermediate Coprox reactors. Provided by Hynergreen fromAbengoa, the system transforms the bioethanol (BioEtOH) into high purityhydrogen. The output feeds a series offuel cells fromUTC Power company.[citation needed]
The reformator is fed with bioethanol as fuel andoxygen (stored as a liquid in a high pressure cryogenic tank), generating hydrogen andcarbon dioxide as subproducts. The produced hydrogen and moreoxygen is fed to thefuel cells.[citation needed]
The bioethanol-processor also produces a stream of highly concentrated carbon dioxide and other trace gases that are not burned completely during combustion. This gas flow is mixed with sea water in one or moreejector venturi scrubber and then through a new system, SECO2 (or CO2 Removal System), developed byBionet, and whose purpose is to dissolve the "bubbles" of CO2 in water to undetectable levels.[36]
The oxygen and fuel flow rates are directly determined by the demand for power. The AIP power in the S-80 submarine is at least 300 kW (400 hp).[36] A permanent-magnet electric motor moves a fixed propeller of a special design, that doesn't createcavitations at high speed.[citation needed]
As operation of the engine can produce noise that resonates through the boat, the engines are mounted on flexible RATO-S G-561W couplings fromVulkan.[37]
In December 2020, the Spanish Ministry of Defence announced the development of a Spanish fuel cell due to the high cost of the current SPC and to avoid the dependence on a foreign manufacturer. The program has a 6-year horizon to develop a 300 kW prototype.[38]
S-80 Plus-class submarines are designed to improve threat scenario missions. Their operational mobility will allow them to operate in remote areas, traveling discreetly at high speeds. Theirair-independent propulsion (AIP) system, of new technological design, will ensure their ability to remain in an area for a very long period of time without being detected and their ability to operate in possible conflict zones.[39]
Capabilities include:
A combat system for multiple target acquisition in different scenarios
The ability to transport personnel, including special operations forces
Low noise and magnetic signatures in order to minimize detection
Low radar and infrared signatures in order to minimize detection
Navantia has confirmed to the press that it has pitched an offer to sell submarines and build a submarine base and training center for thePhilippine Navy.[46][47] The submarine base specifically points to a location inOrmoc, Leyte.[48]
Larsen & Toubro and Navantia signed a Teaming Agreement (TA) for the purpose of submission of a techno-commercial bid for theProject-75 (India) submarine acquisition project.[49][50] Spain has said that its submarine, in contention for a Rs 43,000 crore procurement order by the Indian Navy, has been declared technically compliant and will be ready for trials in a few months.[51]
In January 2025, the S-80 lost the competition, as India considers that the lack of an experienced AIP system made it an unsuitable candidate.[52]
The S-80 design was not accepted as a contender for theWalrus-class replacement program following an initial assessment & selection (B-letter) in 2019.[53] In 2022 theSpanish Ministry of Defence sent a letter to the DutchDefensie Materieel Organisatie [nl] for Navantia to be allowed to put in an offer following aRFQ sent to the remaining contenders, in which some of the requirements had changed. It is rumoured that the request was denied by DMO.[54]
The Polish Navy is planning to purchase 3 attack submarines as part of its Orka programmeunder which the S-80 was offered. Ultimately, the offer was selectBlekinge-class[55][56].
Type 214 submarine - A class of export-oriented diesel-electric attack-submarines, also developed by ThyssenKrupp Marine Systems and currently operated by the navies ofGreece,Portugal,South Korea andTurkey.
Type 218SG submarine - A class of extensively-customised diesel-electric attack-submarines developed ThyssenKrupp Marine Systems and currently operated bySingapore.
Dolphin-class submarine - A class of extensively-customised diesel-electric attack-submarines developed by ThyssenKrupp Marine Systems and currently operated byIsrael.
Dakar-class submarine - A unique class of diesel-electric attack-submarines developed by ThyssenKrupp Marine Systems and currently being built for Israel.
Spanish Navy
Philippines
India (6)
Netherlands (4)
Poland (3)
Turkey