Editing Walrus-class submarine

{{Short description|Attack submarine class of the Royal Netherlands Navy}}
{|{{Infobox ship begin}}
{{Infobox ship image
 | Ship image =  4 walrusklasse onderzeeboten.jpg
}}
{{Infobox ship class overview
 | Name=''Walrus'' class
 | Builders =[[Rotterdamsche Droogdok Maatschappij]]
 | Operators = {{navy|Netherlands}}
 |Cost= [[Guilder|ƒ]]500 million per unit (1992)<ref>{{cite web|author=Jaime Karremann |url=https://marineschepen.nl/kosten-onderzeeboten.html |title=Hoeveel kost de Onderzeedienst? |publisher=marineschepen.nl |date=2013-03-15|language=nl|access-date=2018-03-18}}</ref>
 | Class before =*{{sclass|Dolfijn|submarine|4}}
*{{sclass|Zwaardvis|submarine|4}}
 | Class after = {{sclass|Orka|submarine|4}}
 | Subclasses = 
 | Built range =1979–1992
 | In commission range = 1990–present
 | Total ships building = 
 | Total ships planned = 6<ref name="Nooteboom144">Nooteboom (2001), p. 144.</ref>
 | Total ships completed = 4
 | Total ships cancelled = 2
 | Total ships active =  3
 | Total ships laid up = 
 | Total ships lost = 
 | Total ships retired = 1
 | Total ships preserved = 
}}
{{Infobox ship characteristics
 | Hide header = 
 | Header caption = <ref name="Horneman1011">Horneman (2018), pp. 10-12.</ref><ref name="Amstel59">van Amstel (1991), p. 59</ref><ref name="Nooteboom182">Nooteboom (2001), p. 182.</ref>
 | Ship class=
 | Ship type =  [[Diesel-electric transmission|Diesel-electric]] [[attack submarine]]
 | Ship displacement =*2,450 t surfaced,
* 2,800 t submerged,
* 1,900 t standard
 | Ship length ={{convert|67.725|m|ftin|abbr=on}}
 | Ship beam ={{convert|8.40|m|ftin|abbr=on}}
 | Ship draft ={{convert|6.60|m|ftin|abbr=on}}
 | Ship propulsion = *1 shaft (5 blades)
*3 x [[SEMT Pielstick]] PA4 200 VG [[diesel engine]]s {{cvt|6300|hp}} 
*1 x HOLEC electric motor 
*420-cell [[VARTA]] batteries
 | Ship speed =*{{convert|13|kn}} surfaced,
* {{convert|21|kn}} submerged
 | Ship range =  {{convert|18500|km|nmi|abbr=on}} at {{convert|9|kn|abbr=on}}
 | Ship endurance = 
 | Ship test depth =  >{{Convert|300|m|abbr=on}}
 | Ship complement =  49 to 52
 | Ship sensors =*'''Radars''':
* [[Signaal]]/[[Decca Radar|Decca]] 1229
* [[Signaal]] ZW-07
* Argo Phoenix I
* '''Sonar Systems''':
* Thomson Sintra TSM 2272 Eledone Octopus
* GEC Avionics Type 2026 towed array
* Thomson Sintra DUUX 5 passive ranging and intercept
* '''Fire-control system''':
* [[Thales Nederland|HSA]] GIPSY (SEWACO VIII)
 | Ship EW = 
 | Ship armament =
* 4 × 21-inch (533 mm) [[torpedo tube]]s 
*20 × [[Honeywell]] [[Mark 48 torpedo|Mk 48]] torpedoes or Honeywell [[Mark 37 torpedo|NT 37 C/D/E]] torpedoes
*[[Harpoon (missile)|UGM-84 Harpoon]] [[Surface-to-surface missile|SSM]]  
*40 [[Naval mine|mines]]
 | Ship notes = 
}}
|}

The '''''Walrus''-class submarine''' is the only [[submarine]] class currently in operation in the [[Royal Netherlands Navy]]. The boats have been in service since 1990 and are all named after [[sea mammal]]s.

==Background==
In 1974, the [[Royal Netherlands Navy]] announced, through the [[Ministry of Defence (Netherlands)|Ministry of Defence's]] 10-year plan {{interlanguage link|Defensienota 1974|lt=''Defensienota 1974''|nl}}, that it wanted to replace its aging {{sclass|Dolfijn|submarine|1}}s.<ref name="defensienota1974">H. Vredeling, C.L.J. van Lent, A. Stemerdink, p. 61.</ref> Since the 1960s, the Royal Netherlands Navy had been conducting studies and research into a suitable replacement attack submarine.<ref name="GlobalSecurity">{{cite web|url=https://www.globalsecurity.org/military/world/europe/walrus.htm|title=Walrus|work=www.globalsecurity.org | access-date=22 June 2018}}</ref> This research initiative concluded that the Netherlands should build conventional diesel-electric submarines, as nuclear submarines were costly and could only be constructed, crewed, and maintained by countries with major navies such as the United States, France and the United Kingdom. Nonetheless, even with the diesel-electric submarine, the Dutch government sought to work together with international allies to reduce construction costs.<ref name="defensienota1974" />

[[File:Bouw van de Zeeleeuw (S803) bij de Rotterdamsche Droogdok Maatschappij (2158 017232).jpg|thumb|left|The Walrus-class ''Zeeleeuw'' under construction at Rotterdam in 1987]]
Between 1975 and 1978, the design of the ''Walrus'' class was for the most part completed, and included many improvements which would result in new, state-of-the-art submarines that would mark a significant improvement over previous submarines used by the Royal Netherlands Navy.<ref name="auto2">{{cite web|url=http://www.navyinside.nl/frontpage/onderzeeboten_walrusklasse|title=Onderzeeboten "Walrusklasse"|work=www.navyinside.nl|access-date=27 March 2018|archive-url=https://web.archive.org/web/20180328041240/http://www.navyinside.nl/frontpage/onderzeeboten_walrusklasse|archive-date=2018-03-28|url-status=dead}}</ref> For example, a special kind of French-produced steel was used to construct the hull of the ''Walrus''-class submarines; this steel proved to be more elastic, allowing submarines of the class to dive deeper than previous submarines.<ref>Miller and Miller (1986), p. 171.</ref> Furthermore, there was a focus on automation which was aimed at decreasing the manpower required to operate the submarines, while also making them more effective against threats.<ref name="auto1">{{cite web|url=https://marineschepen.nl/schepen/walrus.html|title=Walrusklasse onderzeeboten |work=www.marineschepen.nl |date=10 November 2016 | access-date=27 March 2018}}</ref>

On 19 June 1979, [[Ministry of Defence (Netherlands)|Minister of Defense]] [[Willem Scholten]] signed a contract worth 425&nbsp;million [[Dutch guilder|guilders]] with the [[Rotterdamsche Droogdok Maatschappij]] (RDM) to build two submarines to replace the ''Dolfijn''-class submarines, with the construction of the second boat to commence the following year.<ref name="rdmarchiefwalrus">{{cite web|url=https://www.rdm-archief.nl/RDM-NB/RDM-348.html|title=Bouwnummer RDM-348, Hr. Ms. "Walrus", 1992, onderzeeboot. |work=www.rdm-archief.nl | access-date=22 June 2018}}</ref> Soon, RDM noticed that the new submarines could not be built the same way as the {{sclass|Zwaardvis|submarine|1}}s; it had to use new techniques to build the submarines.<ref name="auto2"/> Furthermore, the design was constantly modified to incorporate new developments in the submarine world, which led to issues that slowed the building process.<ref name="auto1" /> Nonetheless, construction continued and on 11&nbsp;October 1979, {{HNLMS|Walrus|1985|6}} was laid down.<ref name="Nooteboom144" /> Two years later, on 24&nbsp;September 1981, {{HNLMS|Zeeleeuw|1987|6}} was laid down.<ref name="Amstel59" />

Unexpectedly, on 19 February 1983, [[Rotterdamsche Droogdok Maatschappij|RDM]]'s parent company [[Rijn-Schelde-Verolme]] declared bankruptcy, despite successive governments providing 2.2&nbsp;billion guilders in state aid to RSV.<ref>{{cite web|url=https://nos.nl/artikel/475776-rsv-debacle-viert-30ste-verjaardag.html|title=RSV-debacle viert 30ste verjaardag|language=nl|work=www.nos.nl |date=19 February 2013 | access-date=22 June 2018}}</ref><ref name="anderetijdenRSV">{{cite web|url=https://anderetijden.nl/aflevering/175/De-RSV-enquete|title=De RSV-enquête|language=nl|work=www.anderetijden.nl |date=19 February 2012 | access-date=22 June 2018}}</ref> This was problematic because the construction of the ''Walrus''-class submarines was far from completion. To ensure construction of the submarines continued, RDM was re-established as an independent company.<ref name="Nooteboom144" /> Furthermore, the Royal Netherlands Navy ordered an additional two ''Walrus''-class submarines earlier than planned to assist RDM financially.<ref name="auto1" /> However, at this time the ''Walrus''-class submarines were facing many problems.<ref>{{cite web|url=https://leiden.courant.nu/issue/LD/1984-11-21/edition/0/page/5|title=Kamer stemt in met 'zuivering': Reorganisatie van marinetop|language=nl|work=www.leiden.courant.nu |date=21 November 1984 | access-date=22 June 2018}}</ref> One of these problems was that the specifications of the ''Walrus'' class submarines were only finalized in 1984.<ref name="MSEekelen2019">{{cite web |author=W. F. van Eekelen |url=https://militairespectator.nl/artikelen/nieuwe-onderzeeboten-nieuwe-risicos-en-nieuwe-kansen|title=Nieuwe onderzeeboten, nieuwe risico’s en nieuwe kansen|language=Dutch|website=Militaire Spectator |date=23 October 2019}}</ref> Since construction had already started by that time, the first two boats had to be lengthened by 1 meter, at a cost of 10 million Dutch guilder per boat, to fit all equipment.<ref name="MSEekelen2019" />

[[File:Onderzeeboot Hr.Ms. Walrus (S802) De Walrus gaat "op wieltjes" (2158 016772).jpg|thumb|left|''Walrus'' in 1987 following repairs after the fire which resulted in serious damage to the command centre]]
New problems arose on 14 August 1986, when the command centre of ''Walrus'' caught fire, while it was still on a scaffold in the shipyard.<ref name="auto3">de Bles, Boven and Homburg (2006), p. 104</ref> The fire lasted about five hours, and resulted in immense damage to the submarine; the command center was completely burned out.<ref name="RDMarchiefbruinvis">{{cite web|url=https://www.rdm-archief.nl/RDM-NB/RDM-353.html|title=Bouwnummer RDM-353, Hr. Ms. "Bruinvis", 1994, onderzeeboot.  |work=www.rdm-archief.nl | access-date=16 June 2018}}</ref> While some equipment could be rescued, most had to be replaced.<ref name="auto1"/> This delayed the construction of the submarines once again because the equipment that was ordered for the next boats had to be transferred to finish the ''Walrus''.<ref>Grove (1990), p. 179.</ref> The costs of the resulting damage from the fire was 225&nbsp;million guilders, which was fully covered by insurance.<ref name="RDMarchiefbruinvis" /><ref>Horneman (2018), p. 17.</ref> The exact location, origin and cause of the fire was never established.<ref name="Nooteboom148">Nooteboom (2001), p. 148.</ref> Presumably, the fire was caused in the vicinity of the corporals and men's washroom by a defect in the electrical work lighting.<ref name="Nooteboom148" /> Repairs were reported as complete in 1987,<ref name="auto2"/> but had so delayed construction of ''Walrus'' that the second submarine (with construction number 349) was put into service as the first of the class, with the name HNLMS ''Zeeleeuw'' (sea lion). HNLMS ''Walrus'' was put into service two years later. The two other boats were put into service as {{HNLMS|Dolfijn|1990|6}} and {{HNLMS|Bruinvis|1992|6}} (porpoise). The delays meant that {{HNLMS|Dolfijn|S808}}, {{HNLMS|Potvis|S804|6}} and {{HNLMS|Tonijn|S805|6}} of the ''Dolfijn'' class had to remain in service longer than planned.<ref name="RDMarchiefbruinvis" /> All the problems, delays and rising costs were eventually dubbed by the [[House of Representatives (Netherlands)|Dutch national parliament]] as the "Walrus-affair".<ref name="auto3"/> Nonetheless, at the time of their commissioning, the ''Walrus''-class submarines were considered to be one of the most modern and advanced conventional submarines in operation.<ref name="auto2"/>

==Design==
[[File:Onderzeeboot Hr.Ms. Zeeleeuw (S803), in de kuip op uitkijk (2158 017261).jpg|thumb|left|Inside the conning tower]]
[[File:Onderzeeboot Hr.Ms. Zeeleeuw (S803) interieur, centrale (2158 017254).jpg|thumb|right|Operations compartment aboard ''Zeeleeuw'', 1998]]
[[File:Onderzeeboot Hr.Ms. Zeeleeuw (S803) boegbuiskamer. Torpedoladen (2158 017264).jpg|thumb|right|Torpedo room aboard ''Zeeleeuw'']]
The ''Walrus''-class submarine was designed by Jan Jaap van Rijn, at the time Chief Bureau of Submarines ([[Dutch language|Dutch]]: Hoofd Bureau Onderzeeboten) at the Directorate of Materiel of the Royal Netherlands Navy ([[Dutch language|Dutch]]: Directie Materieel van de Koninklijke Marine).<ref>{{cite web |author=Jaime Karremann |date=17 December 2014 |title=Exclusief interview over ontwerp en bouw Walrusklasse onderzeeboten |url=https://marineschepen.nl/dossiers/ontwerp-en-bouw-walrus-klasse-onderzeeboten.html |website=Marineschepen.nl |language=Dutch}}</ref><ref>{{cite web |author=Jaime Karremann |date=18 December 2014 |title=De oude ingenieurs over de nieuwe onderzeeboten (Deel II) |url=https://marineschepen.nl/dossiers/nieuwe-onderzeeboten-volgens-ontwerpers-walrusklasse.html |website=Marineschepen.nl |language=Dutch}}</ref><ref>{{cite magazine |author=<!-- not stated --> |date=March 2021 |title=Ing. JJ van Rijn, “Het Brein” |url= |magazine=Klaar voor Onderwater|volume=44 |issue=155 |location=Den Helder |pages=17-19}}</ref>

The ''Walrus''-class submarines are unusual in that instead of a cross-shaped assembly of stern [[diving plane]]s and [[rudder]]s, they mount four combined rudders and diving planes in an "X" configuration.<ref name="walrusnavaltechnology">{{Cite web|url=https://www.naval-technology.com/projects/walrus-class-submarines/|title=Walrus-Class Submarines|website=www.naval-technology.com|access-date=2018-06-22}}</ref> This tail configuration was first tested in 1960 on the [[United States Navy]]'s {{USS|Albacore|AGSS-569|6}}, and has since been used by the ''Walrus'' class, all [[Swedish Navy]] submarines since the {{sclass|Sjöormen|submarine|4}}, the [[Royal Australian Navy]]'s {{sclass|Collins|submarine|4}}, the [[German Navy]] [[Type 212 submarine|Type&nbsp;212A]] and the [[Japan Maritime Self-Defense Force]]'s {{sclass|Sōryū|submarine|4}}. The X configuration is a complex system and therefore not implemented by many other navies around the world.<ref name="GlobalSecurity"/>

The submarines of the ''Walrus'' class, when submerged, are silent and therefore difficult to detect by ships, planes and other submarines once they go into hiding.<ref name="defensieonderzeeboten">{{Cite web|url=https://www.defensie.nl/onderwerpen/materieel/schepen/onderzeeboten|title=Onderzeeboten|website=www.defensie.nl|language=nl-NL|access-date=2018-06-22|date=2015-11-30}}</ref> This makes the boats very suitable for combating surface vessels and submarines, protecting friendly units, gathering information, providing early warning detection, and supporting special operations. The submarines can also be used to enforce international sanctions, as they did during the [[Yugoslav Wars]].<ref>{{Cite web|url=https://sail.nl/schepen/marineschepen/onderzeeboten|title=Onderzeeboten|website=www.sail.nl|language=nl-NL|access-date=2017-12-17|archive-url=https://web.archive.org/web/20180330012330/https://sail.nl/schepen/marineschepen/onderzeeboten|archive-date=2018-03-30|url-status=dead}}</ref>

The ''Walrus''-class submarines were specifically designed for hunting Russian submarines during the [[Cold War]].<ref name="deblesbovenhomburg" /> However, the Cold War had ended by the time they became operational. Nonetheless, they have provided excellent services in various international conflict situations in which the deployment of the [[Royal Netherlands Navy]] was requested.<ref name="auto3" /> Since the Dutch submarines have acquired a good reputation, they are often part of international exercises, taking part in mock battles.<ref name="defensieonderzeeboten" /><ref name="defensieionfocus">{{Cite web|url=https://english.defensie.nl/downloads/leaflets/2017/04/20/the-royal-netherlands-navy-in-focus|title=The Royal Netherlands Navy in Focus|website=www.defensie.nl|language=nl-NL|page=35|date=2017-04-20|access-date=2018-06-22|archive-url=https://web.archive.org/web/20180622140151/https://english.defensie.nl/downloads/leaflets/2017/04/20/the-royal-netherlands-navy-in-focus|archive-date=2018-06-22|url-status=dead}}</ref>

In March 2023 it was reported that the Dutch government wants to buy [[Tomahawk (missile family)|Tomahawks]] for the ''Walrus'' class submarines.<ref>{{cite web |url= https://marineschepen.nl/nieuws/Maritime-strike-voor-LCF-en-Walrusklasse-150323.html |title= Langeafstandsraketten voor fregatten en onderzeeboten; Tomahawk testlancering in 2024 |author= Jaime Karremann |date=16 March 2023|website= Marineschepen.nl |language=Dutch}}</ref><ref>{{cite magazine |last=Zijlstra |first=Martin |date=11 April 2023 |title=Onderzeeboot en LCF krijgen ‘lange arm’ |url=https://magazines.defensie.nl/allehens/2023/03/03_tomahawks |magazine=Alle Hens |publisher=Koninklijke Marine |language=Dutch}}</ref> The Tomahawks would be the Torpedo Tube Launch (TTL) version, which can be fired from the torpedo tubes of the submarines.<ref>{{cite web |url= https://www.navalnews.com/naval-news/2023/04/netherlands-selects-tomahawk-to-arm-frigate-and-submarines/ |title= Netherlands Selects Tomahawk to Arm Frigate and Submarines |author= Tayfun Ozberk |date=13 April 2023|website= Naval News}}</ref> However, at the same time it was also stated that if the delivery of this version of the Tomahawk would take too long to deliver it might not be feasible to integrate them on the ''Walrus'' class, as these submarines will replaced in the 2030s by a [[Orka-class submarine|new class of submarines]].<ref>{{cite web |url= https://marineschepen.nl/nieuws/Marine-krijgt-Tomahawk-kruisvluchtwapen-040423.html|title= In 2027 eerste Nederlandse fregat met Tomahawk |author= Jaime Karremann |date=4 April 2023|website= Marineschepen.nl |language=Dutch}}</ref> In May 2025 it was disclosed that the ''Walrus'' class submarines will not be equipped with Tomahawks.<ref>{{cite report |author= |date=21 May 2025 |title=Defensie Projectenoverzicht 2025 |url=https://www.defensie.nl/binaries/defensie/documenten/publicaties/2025/05/21/defensie-projectenoverzicht-2025/web_202500503_DPO+Rapportage+2025.pdf |website=Defensie.nl |publisher=Ministry of Defence |language=Dutch |page=63}}</ref><ref>{{cite web |author=Xavier Vavasseur |date=23 May 2025 |title=Netherlands abandons Tomahawk integration in submarines |url=https://www.navalnews.com/naval-news/2025/05/netherlands-abandons-tomahawk-integration-in-submarines/ |website=Naval News}}</ref>

==Operational history==
[[File:Onderzeeboot Hr.Ms. Zeeleeuw (1990-). Boven water varend (2158 042290).jpg|thumb|right|Aerial view of ''Zeeleeuw'']]
After the Cold War, the submarines have been tasked with many highly confidential intelligence gathering operations, many of which are still classified.<ref>{{cite magazine |last=Koenen |first=Sander |date=September 2009 |title=Kopje Onder  |url=https://www.klaarvooronderwater.nl/kvo/Kvo-109.pdf |magazine=Klaar Voor Onderwater |location=Den Helder |publisher=Onderzeedienst Reünistenvereniging |issue=109|volume=32 |pages=3-9 |language=Dutch}}</ref> They have operated in the Northern Atlantic, Mediterranean Yugoslavian region, the Persian Gulf at Iran and Iraq, and the [[Caribbean]], often upon the request of allies, including the United States.<ref name="deblesbovenhomburg">de Bles, Boven and Homburg (2006), pp. 104–105</ref>

In June 2010, the Netherlands agreed to deploy one submarine to help combat [[piracy off the coast of Somalia]].<ref>{{cite news|title=Nederlandse Onderzeeboot tegen piraten|url=https://www.parool.nl/nieuws/nederlandse-onderzeeboot-tegen-piraten~b57ed492|date=2010-06-22}}</ref>

In November 2016, the [[Russian Navy]] claimed to have chased off a ''Walrus''-class vessel from a battle group that included the {{ship|Russian aircraft carrier|Admiral Kuznetsov|4=2}}.<ref>{{cite news|title=Russia ships 'chase away' Dutch submarine in Mediterranean|url=https://www.bbc.co.uk/news/world-europe-37928222|publisher=BBC|access-date=10 November 2016|date=2016-11-09}}</ref>

===Submarine command course===
[[File:Onderzeeboot Hr.Ms. Zeeleeuw (S803) interieur, machinekamer (2158 017256).jpg|thumb|left|Engine room aboard ''Zeeleeuw'']]
The ''Walrus''-class submarines are used for the [[Submarine Command Course]] (SMCC) for both national and international candidates (including the UK, Australia and Canada), selecting and training future commanders of conventional submarines. They are highly rated, with an exceptional reputation.<ref>de Bles, Boven and Homburg (2006), p. 105</ref> The Royal Netherlands Navy began this course after the British [[Royal Navy]] phased out their conventional submarines.

==Upgrade program==
[[File:De Zr.Ms. Zeeleeuw in 2014 voor onderhoud op de wal.JPG|thumb|{{HNLMS|Zeeleeuw|1987|6}} being upgraded in 2014]]
In 2007, the [[Cabinet of the Netherlands|Dutch cabinet]] approved an upgrade of the four operational submarines and recruitment of additional crew to improve overall operational availability.<ref name="auto">{{cite web|url=https://magazines.defensie.nl/allehens/2016/01/04_update-walrusklasse |title=Terug in de eredivisie |date=10 February 2016 |last=Twigt |first=André |access-date=23 November 2017}}</ref> The upgrades were focused on near-shore operations and integration with new weapons, and include:
* The migration from the [[Mark 48 torpedo|MK 48 mod-4 torpedo]] to the mod-7 version<ref>{{Cite web |url= https://magazines.defensie.nl/materieelgezien/2016/06/mg201607life-extension-ozb |title= Opknapbeurt voegt dimensie toe |author= André Twigt |date=30 September 2016|website= Materieelgezien |publisher= Defensie.nl |language=Dutch}}</ref>
* Replacing one [[periscope]] with a non-hull-penetrating optronic mast from [[L-3 Communications|L-3 KEO]] which enables the submarine to capture HD footage, both day and night<ref>{{Cite web |url= https://magazines.defensie.nl/materieelgezien/2015/04/04zeeleeuw |title= Beter zicht voor de Zeeleeuw |author= Pieter van Geldere |date=5 June 2015|website= Materieelgezien |publisher= Defensie.nl |language=Dutch}}</ref>
* Addition of a mine and obstacle avoidance sonar by ELAC Nautik
* Refurbishing of the pressure hull<ref name="KA2012KVO">{{cite magazine |last=Kesseler  |first=Andre |date=December 2012 |title=Klaar voor het bruine water |url=https://www.klaarvooronderwater.nl/kvo/Kvo-122.pdf |magazine=Klaar Voor Onderwater |location=Den Helder |publisher=Onderzeedienst Reünistenvereniging |issue=122|volume=35 |pages=11-16 |language=Dutch}}</ref>
* Introduction of a new combat management system<ref name="KA2012KVO" />
* Modifications to support special operations forces

In 2013, the contract for the ''Walrus''-class (IP-W) Conservation Program was signed.<ref>{{cite web|url=https://maritiemnieuws.nl/47167/imtech-marine-ontvangt-meerjarige-opdracht-voor-modernisering-van-onderzeeboten/ |title=Imtech Marine ontvangt meerjarige opdracht voor modernisering van onderzeeboten |date=23 May 2013 |language=nl|access-date=22 June 2018}}</ref> The program covered the preservation of the pressure skin, the replacement of the sonar, navigation periscope and GIPSY combat system, improved communication systems and adaptations to a number of platform systems.<ref>{{cite web|url=https://www.kijkmagazine.nl/nieuws/upgrade-nederlandse-onderzeeboten-van-start/ |title=Upgrade Nederlandse onderzeeboten van start |date=13 May 2013 |last=Kesseler|first=André|language=nl|access-date=22 June 2018}}</ref> The Dutch industry and knowledge institutes were heavily involved in the program via the [[Dutch Underwater Knowledge Centre]].<ref>van Kesteren (2020), p. 13.</ref><ref>Horneman (2018), p. 82.</ref><ref>{{cite web |url= https://www.vno-ncw.nl/forum/verborgen-wapen-onderzeeboten-vol-nederlandse-techniek   |title= Verborgen wapen: onderzeeboten vol Nederlandse techniek |author= <!--Not stated-->|date= 15 May 2017|website= VNO-NCW |language=Dutch}}</ref> It was predicted that the upgrade program would lead to a estimated 400.000 man-hours of work for each boat.<ref>{{cite magazine |last=Booy  |first=Arie |date=September 2012 |title=Maatwerk in een bakbeest |url=https://www.klaarvooronderwater.nl/kvo/Kvo-121.pdf |magazine=Klaar Voor Onderwater |location=Den Helder |publisher=Onderzeedienst Reünistenvereniging |issue=121|volume=35 |pages=9-10 |language=Dutch}}</ref> All four boats were to be modernized by 2019. With the conservation program, the boats can be kept operational until mid-2025.<ref>{{cite magazine |last=Steketee  |first=Menno |date=December 2011 |title=Nederlandse onderzeeboten krijgen een nieuwe toekomst |url=https://www.klaarvooronderwater.nl/kvo/Kvo-118.pdf |magazine=Klaar Voor Onderwater |location=Den Helder |publisher=Onderzeedienst Reünistenvereniging |issue=118|volume=34 |pages=5-8 |language=Dutch}}</ref> The cost of upgrading the four submarines was estimated to be 94&nbsp;million euros.<ref>{{cite web|url=https://marineschepen.nl/schepen/walrus.html#ip-w |title=Instandhoudingsprogramma Walrusklasse (IP-W) |date=10 November 2016 |last=Karremann |first=Jaime |access-date=24 November 2017}}</ref> The first boat to be upgraded was {{HNLMS|Zeeleeuw|1987|2}}, followed by {{HNLMS|Dolfijn|1990|2}}, {{HNLMS|Bruinvis|1992|2}} and {{HNLMS|Walrus|1985|2}}.<ref name="auto"/><ref>{{cite web |url=https://www.iv-groep.nl/nl-NL/Nieuws/Archief-2015/The-first-modified-Walrus-class-submarine-has-been |title=Eerste gemodificeerde Walrusklasse onderzeeboot te water, een mooi project van Nevesbu! |date=December 2015 |access-date=24 November 2017 |archive-url=https://web.archive.org/web/20171201031737/https://www.iv-groep.nl/nl-NL/Nieuws/Archief-2015/The-first-modified-Walrus-class-submarine-has-been |archive-date=2017-12-01 |url-status=dead }}</ref><ref>{{cite web|url=https://magazines.defensie.nl/allehens/2017/11/02_de-ultieme-test-mercuur-en-zeeleeuw |title=Mercuur en Zeeleeuw maken nieuwe start |date=2 November 2017 |last=Perreijn |first=Djenna |access-date=25 November 2017}}</ref> The upgrade of ''Zeeleeuw'' took longer than expected.  Initially the upgrade was expected to have been completed by 2015, but it took until 2016 before the submarine was ready for service again. Currently,{{when|date=March 2024}} ''Bruinvis'' is being upgraded at the [[Den Helder]] naval base.<ref name=HNLMS_Walrus_decommissioned_1/> The Royal Netherlands Navy has also begun to prepare for the replacement of the ''Walrus''-class submarines.<ref name="trouwwalrus">{{cite web|url=https://www.trouw.nl/home/wie-mag-de-grootste-militaire-aankoop-sinds-de-jsf-gaan-bouwen-~ade97bfa/|title=Wie mag de grootste militaire aankoop sinds de JSF gaan bouwen?|author=Marno de Boer |work=www.trouw.nl |date=5 June 2018 | access-date=5 June 2018}}</ref>

==Replacement==
{{Main|Walrus-class replacement program}}

In November 2014, the [[Dutch Minister of Defence]] announced plans to replace the ''Walrus''-class submarines<ref>{{cite web|url=http://www.upi.com/Business_News/Security-Industry/2015/01/20/Swedes-Dutch-partner-for-future-submarine-work/2621421769173/ |title=Swedes, Dutch partner for future submarine work |work=UPI.com |date=22 January 2015 |last=Tomkins |first=Richard |access-date=3 March 2015}}</ref> in 2025. By 2017, there was still no political agreement on the quantity or type of new submarines to be ordered, nor the tasks they were expected to perform. However, it seems certain that they will be replaced, since the alleged Russian threat was regarded an incentive to invest in a new class. The Minister of Defence, however, delayed the replacement by two years, until 2027. Roughly, there are two groups in the Dutch parliament – one in favor of replacing the ''Walrus'' class by an equally capable class of large, expeditionary, diesel-electric submarine, and the other in favor of choosing a cheaper solution of smaller diesel-electrics, similar to Swedish and German submarines. It is unknown where the new boats will be built; since the Dutch RDM shipyard (the only Dutch yard capable of building submarines) is no longer in operation. The ''Defensienota'' (Defense policy for the coming years) of March&nbsp;2018 revealed that the Dutch government is still planning to replace the ''Walrus''-class submarines,<ref name="defensienota2018">{{cite web|url=https://www.defensie.nl/downloads/beleidsnota-s/2018/03/26/defensienota-2018 |title=Defensienota 2018|language=nl |publisher=Dutch Ministry of Defense |date=26 March 2018 |access-date=27 March 2018}}</ref> with an allocated budget of more than 2.5&nbsp;billion euros for the new submarines. Additional information on how to proceed with the replacement was expected at the end of 2018, when the Dutch Minister of Defence, [[Ank Bijleveld]], was to send a so-called B-letter to the Dutch parliament.<ref name="defensienota2018" />{{update inline|date=September 2020}} Minister Bijleveld also underlined in an interview that the new submarines should have the same niche capabilities as the current ''Walrus''-class submarines: the ability to operate and gather intelligence in both shallow water close to the coast and in deep water in the ocean.<ref>{{cite web|url=https://www.bndestem.nl/politiek/we-gaan-niet-oplappen-we-gaan-vernieuwen~a2327cae/|title=We gaan niet oplappen, we gaan vernieuwen|language=nl |publisher=BNDeStem |date=27 March 2018 |last1=Keultjes |first1=Hanneke |last2=Boere |first2=Raymond |access-date=27 March 2018}}</ref> In mid-2021 it was indicated that a revised plan envisaged taking a replacement decision in 2022 and to have the first vessel in service by 2028, with the first two boats to be in service by 2031.<ref>{{Cite web|url=https://www.navyrecognition.com/index.php/naval-news/naval-news-archive/2021/june/10233-dutch-navy-walrus-class-submarine-replacement-project-in-progress.html|title = Dutch Navy Walrus-class submarine replacement project in progress| date=June 2021 }}</ref> However, in October 2021 it was reported that this timeline was no longer feasible. Instead, the Dutch Ministry of Defence signalled that the envisaged dates would have to be "substantially adjusted", possibly incorporating a life extension refit for the existing ''Walrus''-class boats.<ref>{{Cite web|url=https://www.navalnews.com/naval-news/2021/10/netherlands-walrus-class-submarine-replacement-program-facing-delays/|title=Netherlands' Walrus-Class Submarine Replacement Program Facing Delays|date=31 October 2021}}</ref>

In April 2022 it was announced that two of the ''Walrus''-class boats would be extended in service until the mid-2030s and that in order to do so safely a different maintenance approach would have to be adopted for the entire fleet with one of the four existing boats to be decommissioned in the short-term, followed by a second boat later.<ref>{{cite magazine |last1=Bode |first1=Jessica |last2=Margés |first2=Joost |date=13 April 2022 |title=Langer door met minder boten |url=https://magazines.defensie.nl/allehens/2022/03/03_ozb |magazine=Alle Hens |publisher=Koninklijke Marine |language=Dutch}} </ref> On 16 November 2022 it was revealed that ''Walrus'' would be the first boat to be decommissioned sometime in 2023.<ref name=HNLMS_Walrus_decommissioned_1>{{Cite web|url=https://marineschepen.nl/nieuws/Onderzeeboot-Walrus-in-2023-uit-dienst-161122.html |title=Onderzeeboot Zr.Ms. Walrus in 2023 uit dienst |publisher=Marineschepen.nl |access-date=22 November 2022 |language=nl}}</ref> ''Walrus'' was decommissioned in October 2023.<ref>{{cite web |last1=Defensie |first1=Ministerie van |title=Zr.Ms. Walrus na 31 operationele jaren uit dienst gesteld - Nieuwsbericht - Defensie.nl |url=https://www.defensie.nl/actueel/nieuws/2023/10/12/zr.ms.-walrus-na-31-operationele-jaren-uit-dienst-gesteld |website=www.defensie.nl |language=nl-NL |date=12 October 2023}}</ref> The revised schedule for the construction of the new replacement boats would likely see the first two vessels entering service in the 2034 to 2037 timeframe.<ref>{{cite web | url=https://www.navalnews.com/naval-news/2022/04/netherlands-to-extend-the-life-of-walrus-class-submarines/ | title=Netherlands to extend the life of Walrus class submarines | date=3 April 2022 }}</ref>

=== Contenders ===
The Ministry of Defence shortlisted three bidders:<ref>{{cite web | url = https://navaltoday.com/2019/12/16/the-netherlands-3-bidders-shortlisted-for-submarine-replacement-program/ | date = 2019-12-16 | title =  The Netherlands: 3 bidders shortlisted for submarine replacement program | work = Naval Today }}</ref><ref>{{cite web | url = https://www.defensenews.com/global/europe/2019/12/17/dutch-walrus-submarine-program-shuffles-forward-but-not-by-much/ | date = 2019-12-17 | title = One bidder out, three remain in Dutch race to replace Walrus subs | first =  Sebastian | last = Sprenger | work = Defense News | publisher = Sightline Media Group }}</ref>
* [[Damen Group]] and [[Saab Group]] announced that they had partnered from 2015 to jointly develop, offer and build next-generation submarines that are able to replace the current ''Walrus''-class submarines.<ref>{{cite web|url=http://www.damen.com/en/news/2015/01/saab_and_damen_team_for_walrus_future_submarine_replacement_programme |title=Saab and Damen Team for Walrus Future Submarine Replacement Programme |work=www.damen.com |date=20 January 2015 | access-date=8 December 2017}}</ref> It was announced on 1&nbsp;June 2018 that their design was to be derived from the [[A26 submarine]].<ref name="DetailsJune2018DamenSaab">{{cite web|url=https://marineschepen.nl/nieuws/Details-voorstel-Saab-Damen-nieuwe-Nederlandse-onderzeeboot-010618.html|title=Meer details voorstel nieuwe Nederlandse onderzeeboot van Saab en Damen|work=www.marineschepen.nl |date=5 June 2018 | access-date=1 June 2018}}</ref><ref name="NIDVJune2018DamenSaab11-12">Stichting Nederlandse Industrie voor Defensie en Veiligheid magazine editie 2-2018 (June 2018), accessed 12 June 2018, pp. 11-12.</ref> The proposed submarine is around {{convert|73|m|ftin|abbr=on}} long with a diameter of {{convert|8|m|ftin|abbr=on}}. Furthermore, the displacement will be around 2,900 tonnes, with a complement of 34 to 42 personnel. The boat's armament includes 6&nbsp;torpedo tubes and 1&nbsp;multi-mission lock which can be used to deploy special forces.<ref name="DetailsJune2018DamenSaab" />
* [[Naval Group]] announced that it was offering its newest submarine class, the [[French Barracuda-class submarine|Barracuda class]], as replacement for the ''Walrus'' class. A version of the "Shortfin" diesel-electric variant Barracuda class was to be offered, rather than the nuclear variant used by the [[French Navy]].<ref>{{cite web|url=https://marineschepen.nl/nieuws/Naval-Group-biedt-Nederland-dieselelektrische-variant-van-nucleaire-barracuda-onderzeeboten-aan-010518.html|title=Franse werf Naval Group wil Nederland dieselelektrische variant van nucleaire onderzeeboot Barracuda aanbieden |work=www.marineschepen.nl |date=1 May 2018 | access-date=1 May 2018}}</ref>
* [[ThyssenKrupp Marine Systems]] was planning to offer a [[Type 212CD submarine|Type 212CD]] submarine.<ref>{{cite web | url = https://www.janes.com/article/93222/netherlands-downselects-contenders-for-submarine-replacement | title = Netherlands downselects contenders for submarine replacement | first = Nicholas | last = Fiorenza | date = 2019-12-16 | work = Jane's 360}}</ref>

Spain's [[Navantia]]'s [[S-80 Plus-class submarine|S-80]] was not accepted as a contender following the B-letter in 2019.<ref name=navantia_1>{{cite web|url=https://marineschepen.nl/nieuws/Navantia-in-tegenaanval-wij-accepteren-redenen-uitschakeling-niet-201219.html |title=Navantia woest: redenen voor uitschakeling "slaan nergens op" |publisher=Marineschepen.nl |date=20 December 2019 |accessdate=22 November 2022 |language=NL}}</ref> In 2022 the [[Ministry of Defence (Spain)|Spanish Ministry of Defence]] sent a letter to the Dutch [[:nl:Defensie Materieel Organisatie|DMO]] for Navantia to be allowed to put in an offer following the announcement that a [[Request for Quotation|RFQ]] will be sent to the remaining contenders, in which some of the requirements had changed. It was rumoured that the request was denied by DMO.<ref name=navantia_2>{{cite web|url=https://marineschepen.nl/nieuws/Spanje-heeft-Defensie-gevraagd-of-Navantia-weer-in-aanbesteding-onderzeeboten-mag-171022.html |title=Spanje heeft om terugkeer in race Nederlandse onderzeeboten gevraagd |publisher=Marineschepen.nl |date=17 October 2022 |accessdate=22 November 2022 |language=NL}}</ref>

On 16 November 2022 the RFQ was sent out to the three remaining shipyards. It was expected they would submit their bids around mid-2023.<ref name=HNLMS_Walrus_decommissioned_1/><ref name=RFQ_sent>{{Cite web|url=https://www.navalnews.com/naval-news/2022/11/netherlands-submarine-replacement-program-rfq-sent-to-3-shipbuilders/ |title=Netherlands' Submarine Replacement Program: RFQ Sent To 3 Shipbuilders |date=16 November 2022 |publisher=Naval News |access-date=22 November 2022 |language=EN}}</ref> In June 2023 it was reported that the three shipyards had to submit their bids by 28 July 2023 at the latest.<ref>{{cite web |url=https://www.navyrecognition.com/index.php/naval-news/naval-news-archive/2023/june/13238-netherlands-ministry-of-defence-explains-award-process-for-new-submarines.html  |title= Netherlands Ministry of Defence explains award process for new submarines |author=<!--Not stated--> |date=16 June 2023|website=Navy Recognition |publisher= |access-date= |quote=}}</ref>

=== Winning bid ===
On 15 March 2024 State Secretary for Defence [[Christophe van der Maat]] officially announced that [[Naval Group]] from [[France]] has been selected as the winning bid.<ref name=Orka_class_1>{{cite web |url=https://www.defensie.nl/onderwerpen/materieel/nieuws/2024/03/15/bouw-nieuwe-onderzeeboten-voorlopig-gegund-aan-naval |title=Bouw nieuwe onderzeeboten voorlopig gegund aan Naval |publisher=Dutch Ministry of Defense |date=15 March 2024 |access-date=15 March 2024 |language=nl}}</ref><ref name=Orka_class_2>{{cite web |url=https://www.rtlnieuws.nl/nieuws/nederland/artikel/5440314/nieuwe-onderzeeers-heten-orka-zwaardvis-barracuda-en-tijgerhaai |title=Defensie bevestigt miljardenproject: nieuwe onderzeeërs heten Orka, Zwaardvis, Barracuda en Tijgerhaai |publisher=RTL Nieuws |date=15 March 2024 |access-date=15 March 2024 |language=nl}}</ref><ref name=Orka_class_3>{{cite web |url=https://www.navalnews.com/naval-news/2024/03/the-netherlands-select-naval-group-for-its-new-submarines/ |title=The Netherlands Select Naval Group For Its New Submarines |publisher=Naval News |date=15 March 2024 |accessdate=15 March 2024}}</ref> Prior to this announcement, the winner was already leaked to several media outlets, which caused political backlash for choosing a foreign yard over a Dutch one.<ref>{{cite web |url=https://marineschepen.nl/nieuws/Kamerdebat-onderzeeboten-geen-grote-veranderingen-140324.html |title=Kamerdebat onderzeeboten: zorgen en veel aandacht voor Nederlandse industrie, maar geen ingreep |publisher=Marineschepen.nl |date=14 March 2024 |access-date=15 March 2024 |language=nl}}</ref>

The names of the new submarines where also announced by Van der Maat. The class will be known as the {{sclass|Orka|submarine|4}}, with the subs named ''Orka'', ''Zwaardvis'', ''Barracuda'' and ''Tijgerhaai''. The first two will be delivered within ten years after the contract has been signed.<ref name=Orka_class_1/><ref name=Orka_class_2/><ref name=Orka_class_3/>

== Ships in class ==
All boats were built by RDM.

{| class="wikitable" border="1"
|+  ''Walrus'' class construction data<ref name="Nooteboom144" /><ref name="Amstel59" />
|-
! Ship name
! Hull number
! Laid down
! Launched
! Commissioned
! Decommissioned
! Status
|-
| {{ship|HNLMS|Walrus|1985|2}}
| S802
| 11 October 1979
| 28 October 1985 <br /> 13 September 1989 (re-launched)<ref>Horneman (2018), p. 18.</ref>
| 25 March 1992
| 12 October 2023<ref>{{cite web |url=https://marineschepen.nl/nieuws/Onderzeeboot-Walrus-volgende-week-uit-dienst-021023.html |title= Walrus volgende week als eerste onderzeeboot uit dienst |author= Jaime Karremann |date= 2 October 2023|website= Marineschepen.nl |language=Dutch}}</ref>
| Decommissioned and used for spare parts.<ref>{{cite web |url=https://www.defensenews.com/global/europe/2023/10/13/dutch-navy-starts-retiring-submarines-but-successor-still-unknown/ |title= Dutch navy starts retiring submarines, but successor still unknown |author= Rudy Ruitenberg |date= 13 October 2023 |website= Defense News }}</ref>
|-
| {{ship|HNLMS|Zeeleeuw|1987|2}}
| S803
| 24 September 1981
| 20 June 1987
| 25 April 1990
| 
| In service
|-
| {{ship|HNLMS|Dolfijn|1990|2}}
| S808
| 12 June 1986
| 25 April 1990
| 29 January 1993
| 
| In service
|-
| {{ship|HNLMS|Bruinvis|1992|2}}
| S810
| 14 April 1988
| 25 April 1992
| 5 July 1994
| 
| In upgrade program
|}

==See also==
* [[List of submarine classes in service]]
* [[Royal Netherlands Navy Submarine Service]]

==References==
{{reflist}}

===Bibliography===
* KVMO, "Nut en noodzaak onderzeeboten: deltaplan voor defensie" Marineblad Maart 2016 nr 2 Jaargang 126.
* {{citation|title=Onzichtbaar maar onmisbaar: De onderzeeboot en zijn proliferatie|last=Boeke |first=S. |pages=198–208|publisher=MILITAIRE SPECTATOR 175|language=nl|date=2006}}
* {{cite book |last1=de Bles |first1=Harry |last2=Boven |first2=Graddy |last3=Homburg |first3=Leon |date=2006 |title=Onderzeeboten! |language=Dutch|edition= |url= |location=Zaltbommel |publisher=Aprilis |page= |isbn=978-90-5994-130-4}}
* Om de veiligheid van het bestaan: defensiebeleid in de jaren 1974-1983, H. Vredeling, C.L.J. van Lent, A. Stemerdink. Defensienota 1974. Kamerstuknummer 12994 ondernummer 14. {{ISBN|90 12 005361}}.
* {{cite book |last=van Amstel |first=W.H.E. |date=1991 |title=De schepen van de Koninklijke Marine vanaf 1945 |language=Dutch|edition= |url= |location=Alkmaar |publisher=De Alk |page= |isbn=90-6013-997-6}}
* {{cite book |last=Grove |first=Eric J. |date=1990 |title=NATO Major Warships: Europe |location=London |publisher=Tri-Service Press |isbn=1-85400-006-3}}
* {{cite book |last1=Miller |first1=David |last2=Miller |first2=Chris |date=1986 |title=Modern Naval Combat|location=New York |publisher=Crescent Books |isbn=0-517-61350-6}}
* {{cite book |last=Nooteboom |first=S.G. |date=2001 |title=Deugdelijke schepen: marinescheepsbouw 1945-1995 |language=Dutch|edition= |url= |location=Zaltbommel |publisher=Europese Bibliotheek |page= |isbn=90-288-2637-8}}
* {{cite book |editor-last=Horneman |editor-first=G.D. |date=2018 |title=Monografie Nederlandse onderzeeboten|volume=4: Operationele boten|language=Dutch|edition= |url= |location=Soesterberg |publisher=Aspekt|page= |isbn=978-94-6338-381-3}}
* {{cite magazine |author=<!--Staff writer(s); no by-line.-->|editor1-last=van Kesteren |editor1-first=E.E. |title=De Aanloop Naar IPW |magazine=Klaar voor Onderwater: Vereniging voor aktief en oud onderzeedienstpersoneel |location=Julianadorp |publisher=Onderzeedienst Reünistenvereniging|volume=43 |issue=154|issn=2214-6202 |date=December 2020 |pages=13–20|language=Dutch}}

===Further reading===
* {{cite book |editor-last=Darman |editor-first=Peter |date=2004 |title=Twenty-first Century Submarines and Warships |series=Military Handbooks|location=Rochester |publisher=Grange Books |isbn=1-84013-678-2}}
* {{cite book|last1=Jalhay|first1=P.C.|last2=Wijn|first2=J.J.A.|title=Ik nader ongezien! De onderzeeboten van de Koninklijke Marine|year=1997|publisher=De Bataafsche Leeuw|location=Amsterdam|isbn=978-9067074629}}
* {{cite book |editor-last=Saunders |editor-first=Stephen |date= 2015 |title=IHS Jane's Fighting Ships 2015-2016 |location=Coulsdon, Surrey |publisher= Janes Information Group |isbn=978-0-7106-3143-5}}

== External links ==
{{Commons category}}
* [http://nlnavy.damen.com/#submarines ''Walrus''-class submarines]

{{Walrus class submarines}}
{{Modern Dutch submarines}}
{{Post1945DutchShips}}

[[Category:Submarine classes]]
[[Category:Walrus-class submarines| ]]