View source for Gotland-class submarine

{{Short description|Swedish Navy attack submarine class}}
{|{{Infobox ship begin
}}
{{Infobox ship image
| Ship image = Swedish attack submarine HMS Gotland.jpg
| Ship caption = HSwMS ''Gotland''
}}{{Infobox ship class overview
|Builders=[[Kockums]]
|Operators={{navy|SWE}}
|Class before={{sclass|Västergötland|submarine|4}}
|Class after={{sclass|Blekinge|submarine|4}}
|Subclasses=
|Built range=1992–1996
|In commission range=1996–present
|Total ships building=
|Total ships planned=3
|Total ships completed=3
|Total ships cancelled=
|Total ships active=3
|Total ships laid up=
|Total ships lost=
|Total ships retired=
|Total ships preserved=
}}
{{Infobox ship characteristics
| Hide header = 
| Header caption = 
| Ship type = [[Submarine]]
| Ship displacement = *Surfaced: {{convert|1494|t|LT}}
*Submerged: {{convert|1599|t|LT}}
| Ship length = {{convert|60.4|m|ftin|abbr=on}}
| Ship beam = {{convert|6.2|m|ftin|abbr=on}}
| Ship draught = 
| Ship draft = {{convert|5.6|m|ftin|abbr=on}}
| Ship propulsion = *2 × Diesel-electric MTU engines
*2 × Kockums v4-275R Stirling AIP units
| Ship speed = *Surfaced: {{convert|11|kn|km/h|lk=in}}
*Submerged: {{convert|20|kn|km/h}} on batteries; {{convert|5|kn|km/h}} on AIP
| Ship range = 
| Ship endurance = 
| Ship test depth = 
| Ship complement = *18–22 officers
*6–10 ratings
| Ship sensors = CSU 90-2 integrated sonar sensor suite
| Ship EW = 
| Ship armament = *4 × {{convert|533|mm|abbr=on|1}} torpedo tubes
*2 × {{convert|400|mm|abbr=on|1}} torpedo tubes
*48 × Externally mounted [[naval mine]]s<ref>{{cite web |title=SSK Gotland Class (Type A19), Sweden |url=http://www.naval-technology.com/projects/gotland/ |website=naval-technology.com |access-date=2017-09-20}}</ref>
| Ship notes = 
}}
|}

The '''''Gotland''-class submarines''' of the [[Swedish Navy]] are modern [[Submarine#Diesel-electric transmission|diesel-electric submarines]], which were designed and built by the [[Kockums]] [[shipyard]] in Sweden. They are the first submarines in the world to feature a [[Stirling engine]] [[air-independent propulsion]] (AIP) system, which extends their underwater endurance from a few days to weeks.<ref name="kockums">{{cite web | title=The Gotland class submarine - submerged several weeks | website=Kockums | url=http://www.kockums.se/en/products-services/submarines/gotland-class/ | access-date=2008-04-06 | archive-date=2011-04-25 | archive-url=https://web.archive.org/web/20110425220545/http://www.kockums.se/en/products-services/submarines/gotland-class/ | url-status=dead }}</ref> This capability had previously only been available with [[Nuclear submarine|nuclear-powered submarine]]s.

==Features==
As of 2008, the ''Gotland''-class attack submarine is one of the most modern submarines of the Swedish Navy in service, mainly designed for submarine missions such as [[Anti-surface warfare|antiship]]/[[Anti-submarine warfare|antisubmarine]] warfare, collecting of intelligence ([[Signals intelligence#COMINT|communications intelligence (COMINT)]], [[Signals intelligence#ELINT|electronic signals intelligence (ELINT)]]), [[Observation post|forward surveillance]], [[Special forces|special operations]], and [[minelayer|mine-laying]] tasks.<ref name="kockums" />

On the water surface, the submarine is powered by two sets of [[MTU Friedrichshafen|MTU engines]]. While submerged, the Kockums-built Stirling engine AIP system is used to drive a {{convert|75|kW|adj=on|shp|lk=on}} generator for either propulsion or charging the batteries. A Stirling engine is particularly well suited for a submarine because the engine is nearly silent and can use the surrounding sea water as a heat sink to increase efficiency. Submerged [[Endurance (submarine)|endurance]] is dependent on the amount of liquid oxygen stored on-board and is described as "weeks". The class is characterized by its low acoustic signatures, extreme shock resistance, and a competent combat system.<ref name="kockums" />

Kockums touts extreme maneuverability for this class due to the hull design and a well-placed X rudder. The X rudder provides four control surfaces, along with two mounted on the sail, which enables sharp turns and the ability to operate very close to the seabed. Ship automation and computerized steering allow a single operator to steer the submarine in depth and course, which also results in a smaller crew complement, leading to good accommodation standards and low operating costs.<ref name="kockums2">{{cite web | title=Kockums Promotional | website=Naval Technology | url=http://www.sesusa.org/submarine.pdf | access-date=2011-11-21}}</ref>

The class has many features that enhance stealth, helping it to remain undetected. All shipboard machinery is isolated and mounted on rubber dampeners to reduce vibrations and noises; a [[hydrodynamic]] hull design  reduces noise, [[infrared]] signature, and active [[sonar]] response. Its magnetic signature is counteracted by 27 independent [[electromagnets]], short circuiting [[extremely low frequency]] (ELF) electrical fields. Various hull coatings reduce active sonar response, and the mast is coated with [[radar-absorbent material]]. Combined with the near-silent operation of the Stirling generator and slow-turning propeller to prevent [[cavitation]], the boats are very difficult to detect under water, especially in their normal area of operations, the Baltic Sea.<ref name="kockums2"/>

[[File:Gotland class submarine.png|left|thumb|Drawing of the ships in the class]]
{{clear|left}}

==Units==
{| class="wikitable"
|-
!Ship name
!Laid down
!Launched
!Commissioned
!Service
!Status
!Coat of arms
|-
||[[HSwMS Gotland (1995)|HSwMS ''Gotland'' (Gtd)]]
|10 October 1992
|2 February 1995
|1996
|[[Swedish Navy - 1st Submarine Flotilla|1st Submarine Flotilla]]
|Active
|[[File:HMS Gotland vapen, ubåt.svg|center|40px]]
|-
||{{HSwMS|Uppland|Upd}}
|14 January 1994
|8 February 1995
|1996
|[[1st Submarine Flotilla (Sweden)|1st Submarine Flotilla]]
|Active
|[[File:HMS Uppland vapen.svg|center|40px]]
|-
||{{HSwMS|Halland|Hnd}}
|21 October 1994
|27 September 1996
|1996
|[[1st Submarine Flotilla (Sweden)|1st Submarine Flotilla]]
|Active
|[[File:HMS Halland vapen.svg|center|40px]]
|-
|}

==Deployments==
After being refitted and upgraded to sustain the higher temperatures of tropical water,<ref name="knews">[[Kockums]].se: [http://www.kockums.se/news/2000.html News 2000] {{Webarchive|url=https://web.archive.org/web/20110606154845/http://www.kockums.se/news/2000.html |date=2011-06-06 }}</ref> HSwMS ''Halland'' took part in a multi-national exercise in the [[Mediterranean]] from September 16, 2000. Allegedly, there she remained undetected while still recording many of her friendly adversaries, attracting interest from the participating countries. In early November the same year, she participated in a [[NATO]] "blue-water" exercise in the [[Atlantic]]. There, she reportedly won a victory in a mock "duel" with Spanish naval units, and then the same in similar duel against a French SSN, a nuclear-powered attack submarine. She also "defeated" an American SSN, the [[USS Houston (SSN-713)|USS ''Houston'']].<ref name="knews" />

===Secondment to United States Navy===
{{multiple image
|align= right
|width= 150
|image1= Gotland DN-SD-06-07476.JPEG
|width1= 
|caption1= HSwMS ''Gotland'' onboard MV ''Eide'' Transporter in San Diego
|image2= HMS Gotland with USS Ronald Reagan.jpg
|width2= 
|caption2= HSwMS ''Gotland'' transits through San Diego Harbor with the {{sclass|Nimitz|aircraft carrier|1}} {{USS|Ronald Reagan}} following close behind during the "Sea and Air Parade" held as part of Fleet Week San Diego 2005.
}}
[[File:HMS Gotland - Ystad-2015.jpg|thumb|300px|''Gotland'' in the port of [[Ystad]] 2015]]

In 2004, the [[Government of Sweden|Swedish government]] received a request from the [[United States]] to lease HSwMS ''Gotland'' &ndash; Swedish-flagged, commanded and manned, for a duration of one year for use in [[antisubmarine warfare]] exercises. The Swedish government granted this request in October 2004, with both navies signing a [[memorandum of understanding]] on 21 March 2005.<ref>{{cite web | title=US Navy Leasing Swedish Gotland-Class Submarine | website=Deagel | url=http://www.deagel.com/news/US-Navy-Leasing-Swedish-Gotland-Class-Submarine_n000000395.aspx | access-date=2004-11-05}}</ref><ref>{{cite press release|url=http://www.news.navy.mil/search/display.asp?story_id=17621 |title=U.S., Swedish Navies Sign Agreement to Bilaterally Train on State-of-the-Art Sub |publisher=United States Navy |date=2005-03-23 |url-status=dead |archive-url=https://web.archive.org/web/20070819041151/http://www.news.navy.mil/search/display.asp?story_id=17621 |archive-date=2007-08-19 }}</ref> The lease was extended for another 12 months in 2006.<ref>{{cite news|url=http://www.thelocal.se/article.php?ID=3574 |publisher=The Local |title=US Navy to continue hunt for Swedish sub |date=2006-04-18 |access-date=2006-07-21 |url-status=dead |archive-url=https://web.archive.org/web/20090329115136/http://www.thelocal.se/article.php?ID=3574 |archive-date=2009-03-29 }}</ref><ref>{{cite press release|url=http://www.kockums.se/news/060613gotland.html |title=Gotland extends US stay for another year |publisher=Kockums AB |date=2006-06-13 |access-date=2006-07-21 |url-status=dead |archive-url=https://web.archive.org/web/20061001063127/http://www.kockums.se/News/060613gotland.html |archive-date=2006-10-01 }}</ref><ref>{{cite press release|url=http://www.kockums.se/news/070509gotland.html|title=HMS Gotland's Stirling propulsion system basis of success in the USA|publisher=Kockums AB|date=2007-05-09|access-date=2009-06-16|archive-date=2010-09-24|archive-url=https://web.archive.org/web/20100924182055/http://www.kockums.se/news/070509gotland.html|url-status=dead}}</ref> In July 2007, HSwMS ''Gotland'' departed San Diego for Sweden.<ref>{{cite web | title=SSK Gotland Class (Type A19) Attack Submarine, Sweden | website=Naval Technology | url=http://www.naval-technology.com/projects/gotland/ | access-date=2008-04-06}}</ref>

In 2005, HSwMS ''Gotland'' managed to snap several pictures of {{USS|Ronald Reagan}} during a [[Military exercise|wargaming]] exercise in the [[Pacific Ocean]], demonstrating that it was in a position to sink the aircraft carrier.<ref>{{cite news | url=http://www.knbc.com/news/10116514/detail.html | archive-url=https://web.archive.org/web/20071116120858/http://www.knbc.com/news/10116514/detail.html | url-status=dead | archive-date=2007-11-16 | publisher=KNBC | title=Pentagon: New Class Of Silent Submarines Poses Threat | date=2006-10-19 | access-date=2006-07-21}}</ref> The exercise was conducted to evaluate the effectiveness of the US fleet against  [[diesel-electric submarine]]s, which some have noted as severely lacking.<ref>{{cite journal | last=Polmar | first=Norman |date=March 2006 | title=Back to the Future | journal=U.S. Naval Institute Proceedings | volume=132 | issue=3 | pages=22&ndash;23 | id=0041-798X}}</ref><ref>{{cite web | title=US Navy Struggles to Recapture, Keep ASW Proficiency | website=The Nav Log | url=http://navlog.org/asw_feb06.html | access-date=2008-04-06 | archive-url=https://web.archive.org/web/20090202192615/http://navlog.org/asw_feb06.html | archive-date=2009-02-02 | url-status=dead }}</ref> In 2001, during the exercise ''JTFEX 01-2'' in the [[Caribbean Sea]], the [[Germany|German]] ''U24'' of the conventional [[Type 206 submarine|206 diesel-electric class]] "sank" the carrier [[USS Enterprise (CVN-65)|''Enterprise'']] by firing [[flare]]s and taking a photograph through its [[periscope]].<ref>{{cite news | url=https://www.t-online.de/nachrichten/militaer-special/id_61572852/militaer-deutsches-u-boot-fordert-us-marine-heraus-.html | publisher=t-online | title=Deutsches U-Boot fordert US-Marine heraus | date=2013-01-06 | access-date=2020-12-18 | language=de}}</ref>

== Overhaul ==

=== Initial discussions ===
In March [[2013 in Sweden|2013]], Kockums received an initial order for an overhaul for two of the ''Gotland''-class submarines. The overhaul was expected to be completed by 2017. With these upgrades, the submarines would be able to remain in active duty until after 2025.<ref>{{cite web |first=Monica |last=Kleja |title=Kockums får stor ubåtsorder |language=sv |trans-title=Kockums gets big submarine orders |url=http://www.nyteknik.se/nyheter/fordon_motor/fartyg/article3553829.ece |website=[[Ny Teknik]] |date=2012-10-05 |access-date=2017-09-20}}</ref>
On 2 April [[2014 in Sweden|2014]], the Swedish defence minister, insisting on the importance of submarines to the security of Sweden, announced the Government's intent to upgrade two of the ''Gotland''-class vessels, as well as purchase two new "stealth" submarines of another type.<ref>{{cite news |first1=Mats |last1=Knutson |first2=Love |last2=Benigh |title=Regeringen stoppar planerad ubåtsaffär |language=sv |trans-title=The government stops the planned submarine business |url=http://www.svt.se/nyheter/sverige/regeringen-stoppar-planerade-ubatsaffaren-med-kockums |website=[[Sveriges Television|svt]] |date=2014-04-02 |access-date=2017-09-20}}</ref><nowiki/>

=== Mid-life upgrade contract===
Negotiations concluded on 30 June 2015 with the signature of a contract between Sweden's [[Defence Materiel Administration (Sweden)|Defense Material Administration]] (FMV) and [[Kockums Naval Solutions|Saab Kockums]]. In addition to the construction of two new [[A26 submarine|Type 26 A SSKs]], the contract provides for a mid-life upgrade of [[HSwMS Gotland (1995)|HSwMS ''Gotland'']] and her sister ship [[HSwMS Uppland (Upd)|HSwMS ''Uppland'']], for SEK 2.1 billion. ''Gotland'' is expected to return to the FMV in late 2018 and ''Uppland'' in late 2019, following a series of platform and combat systems upgrades. ''Gotland'' returned to active duty in June 2018 after receiving modification for over 20 systems. Same systems will also be included on the new A26 submarines.<ref>{{cite web|url=http://www.fmv.se/sv/Nyheter-och-press/Nyheter-fran-FMV/Sjosattning-av-modifierad-ubat/|title=Sjösättning av modifierad ubåt|first=Hans|last=Ivansson|website=www.fmv.se|access-date=2018-06-20|archive-date=2018-06-21|archive-url=https://web.archive.org/web/20180621015902/http://www.fmv.se/sv/Nyheter-och-press/Nyheter-fran-FMV/Sjosattning-av-modifierad-ubat/|url-status=dead}}</ref> {{HSwMS|Uppland|Upd|6}} relaunched in June 2019<ref>{{cite web|url=https://www.navalnews.com/naval-news/2019/06/second-gotland-class-submarine-hms-uppland-relaunched-following-mlu-by-saab/|title=Second Gotland-class Submarine HMS Uppland Relaunched following MLU by Saab|website=www.navalnews.com|date=21 June 2019}}</ref> and was delivered to the Navy in December 2020.<ref>{{Cite web|url=https://seawaves.com/?p=7860|title = Saab Delivers Modernized Gotland-class Submarine – SeaWaves Magazine}}</ref> In March 2022 FMV and SAAB signed a contract for MLU of HMS Halland<ref>{{cite press release |url=https://www.saab.com/newsroom/press-releases/2022/saab-signs-contract-for-mid-life-upgrade-of-the-third-gotland-class-submarine |title=Saab Signs Contract for Mid-Life Upgrade of the Third Gotland-class Submarine |archive-url=https://web.archive.org/web/20220318223321/https://www.saab.com/newsroom/press-releases/2022/saab-signs-contract-for-mid-life-upgrade-of-the-third-gotland-class-submarine |archive-date=2022-03-18 |url-status=bot: unknown |access-date=2022-03-19 }}</ref>

==See also==
* [[List of submarine classes in service]]
* [[Coastal submarine]]

==References==
{{Reflist|30em}}

==External links==
{{Commons category|Gotland class submarines}}
*[http://www.kockums.se/en/products-services/submarines/gotland-class/ Official Kockums website on ''Gotland'' class submarines] {{Webarchive|url=https://web.archive.org/web/20110425220545/http://www.kockums.se/en/products-services/submarines/gotland-class/ |date=2011-04-25 }}
*[https://web.archive.org/web/20110425220601/http://www.kockums.se/en/products-services/submarines/stirling-aip-system/ Kockum's AIP Stirling system]
*{{youtube|Khaa3y0i87s|NBC news report on the Gotland class}}

{{Gotland class submarine}}
{{ActiveSwedishNavyClasses}}
{{Kockums Naval Solutions}}
{{Authority control}}

[[Category:Gotland-class submarines| ]]
[[Category:Submarine classes]]
[[Category:Naval ships of Sweden]]
[[Category:Submarines of Sweden]]