View source for Cakra-class submarine

{{short description|Submarine class}}
{|{{Infobox ship begin
}}
{{Infobox ship image
| Ship image = Kri cakra 401.jpg
| Ship caption = {{ship|KRI|Cakra|401}}
}}
{{Infobox ship class overview
| Name = ''Cakra'' class
| Builders = [[Howaldtswerke-Deutsche Werft]]
| Operators = {{naval|Indonesia}}
| Class before = {{sclass2|Whiskey|submarine|4}}
| Class after = {{sclass|Nagapasa|submarine|4}}
| Subclasses = 
| Cost = 
| Built range = 1977–1981
| In service range = 
| In commission range = 1981–present
| Total ships on order = 
| Total ships building = 
| Total ships planned = 
| Total ships completed = 2
| Total ships cancelled = 
| Total ships active = 1
| Total ships laid up = 
| Total ships lost = 1
| Total ships retired = 
| Total ships preserved = 
}}
{{Infobox ship characteristics
| Hide header = 
| Header caption = 
| Ship type = [[Attack submarine]]
| Ship displacement = *1,285 tons surfaced <ref name="jfs10p353">{{Harvnb|Saunders|2009|p=353}}</ref> 
*1,390 tons submerged
| Ship length = {{convert|59.5|m|ftin|abbr=on}}
| Ship beam = {{convert|6.2|m|ftin|abbr=on}}
| Ship draft = {{convert|5.4|m|ftin|abbr=on}}
| Ship propulsion = *4 x MTU 12V493 AZ80 GA31L diesel engines rated at {{convert|2,400|hp|MW|abbr=on|lk=on|order=flip}} <ref name=jfs10p353/>
*4 x Siemens alternators rated at {{convert|1.7|MW|hp|abbr=on|lk=on|order=flip}}
*1 x Siemens motor rated at {{convert|4,600|hp|MW|abbr=on|lk=on|order=flip}}
*1 x shaft
| Ship speed = * {{convert|11|kn}} surfaced <ref name=jfs10p353/>
* {{convert|21.5|kn}}  submerged
| Ship range = * {{convert|8,200|nmi|abbr=on}} at {{convert|8|kn|abbr=on}}
| Ship endurance = 50 days <ref name=jfs10p353/>
| Ship test depth = {{convert|240|m|abbr=on}} <ref name=jfs10p353/>
| Ship boats = 
| Ship capacity = 
| Ship complement = 33
| Ship time to activate = 
| Ship sensors = *Signaal Sinbad weapons control system <ref name=jfs10p353/>
*Thomson-CSF Calypso, I-band surface search radar 
*Atlas Elektronik CSU 3-2 active/passive search and attack sonar 
*PRS-3/4 passive ranging
| Ship EW = ESM : Thomson-CSF DR2000U <ref name=jfs10p353/>
| Ship armament = *8 × {{convert|21|in|mm|abbr=on|0|order=flip}} bow tubes <ref name=jfs10p353/>
*14 x [[SUT torpedo|AEG SUT]] torpedoes
| Ship armor = 
| Ship aircraft = 
| Ship notes = 
}}
|}

The '''''Cakra'' class''' ({{lang|id|Cakra}} read "[[chakra]]" which is a [[Sanskrit]] derived word referring to "wheel") is a class of two [[Type 209|Type 209/1300]] [[attack submarine]]s developed by [[Howaldtswerke-Deutsche Werft]] of Germany that were bought and commissioned by the [[Indonesian Navy]] in the 1980s. The second member of the class, {{ship|KRI|Nanggala|402|6}} sank in 2021 with all hands during an [[Military exercise|exercise]]. The [[Lead ship|lead submarine]], {{ship|KRI|Cakra|401|6}}, remains in service.

==Development==
The ''Cakra''-class submarines were ordered on 2 April 1977, designed by [[Ingenieurkontor Lübeck]] of [[Lübeck]], constructed by [[Howaldtswerke-Deutsche Werft]] of [[Kiel]], and sold by [[Ferrostaal]] of [[Essen]] – all acting together as a [[West Germany|West German]] [[consortium]].<ref name=jfs10p353/> They were [[Keel laying|laid down]] on 25 November 1977 and March 1978, and completed on 18 March 1981 and 6 July 1981, respectively. There were plans to build two more boats of the same class but eventually nothing came of it.<ref name="conwaysp179">{{Harvnb|Gardiner|Chumbley|1995|p=179}}</ref>

On 25 September 1997, [[Indonesia]] took over two ex-German [[Type 206 submarine|Type 206]] submarines with plans to refit them, followed by three others. Funds ran out in June 1998 and the whole project was then cancelled. New plans to acquire submarines from [[South Korea]] were announced in October 2003. Then it was revealed that the intended procurement was an improved {{sclass|Jang Bogo|submarine|1}}, the members of which are now in service as the {{sclass|Nagapasa|submarine|4}}.<ref name=jfs10p353/>

==Design==
The ''Cakra''-class submarines have high capacity batteries with GRP [[Lead–acid battery|lead–acid]] cells and battery cooling supplied by Wilhelm Hagen AG.<ref name=jfs10p353/>

===Modernization===
The ''Cakra''-class underwent major refits at HDW spanning three years from 1986 to 1989. These refits were expensive and lengthy and may have discouraged further orders at that time. ''Cakra'' was refitted again at Surabaya from 1993 to April 1997, including replacement batteries and updated Sinbad TFCS. ''Nanggala'' received a similar refit from October 1997 to mid-1999.<ref name=jfs10p353/>

''Cakra'' began another refit at Daewoo Shipyard, South Korea in 2004. It was completed in 2005. Work is reported to have included new batteries, overhaul of engines and modernisation of the combat system. A similar refit of ''Nanggala'' was completed in early 2012.<ref name=jfs10p353/><ref>{{Cite web|last=대우조선해양|date=2012-01-20|title=대우조선해양, 인도네시아 잠수함 성능개량사업 완료|url=http://www.newswire.co.kr/newsRead.php?no=598586|access-date=2021-04-22|website=대우조선해양, 인도네시아 잠수함 성능개량사업 완료 - 뉴스와이어|language=ko}}</ref><ref>{{Cite web |last=Pattisina |first=Edna Caroline |date=2012-02-06 |editor-last=Aziz |editor-first=Nasru Alam |title=Kapal Selam KRI Nanggala Kembali Beroperasi |url=https://nasional.kompas.com/read/2012/02/06/18574511/~Nasional |access-date=2021-04-22 |website=KOMPAS.com |language=id}}</ref>

==Vessels in class==
{|class="wikitable"
! Name
! Hull number
! Builder
! Ordered
! Laid down
! Launched
! Commissioned 
! Status
|-
| {{ship|KRI|Cakra|401|2}}
|401
|align=center rowspan=2 | [[Howaldtswerke-Deutsche Werft|Howaldtswerke]]
|2 April 1977
|25 November 1977
|10 September 1980
|18 March 1981
|In active service <ref name=jfs10p353/><ref name=conwaysp179/>
|-
| {{ship|KRI|Nanggala|402|2}}
|402
|2 April 1977
|March 1978
|10 September 1980
|6 July 1981
|Went missing on 21 April 2021 and declared sunk on 24 April, following the retrieval of objects believed to have been parts of the submarine, including a torpedo straightener.<ref>{{Cite web|last=Archus|first=Dorian|title=Indonesian Navy lost communication with the submarine after training - Naval Post|url=https://navalpost.com/indonesian-navy-lost-communication-with-submarine/|access-date=2021-04-21|language=en-US}}</ref><ref name="NanggalaSunk">{{Cite web|title=Indonesian searchers recover debris from missing submarine|url=https://www.aljazeera.com/news/2021/4/24/indonesian-searchers-recover-debris-from-missing-submarine|access-date=2021-04-24|language=en|author=Al Jazeera}}</ref> Found on the 25th April, all hands lost.<ref name="NanggalaFound">{{Cite web|title=Indonesian searchers recover debris from missing submarine|url=https://www.aljazeera.com/news/2021/4/25/indonesia-authorities-say-53-submarine-crew-are-dead|access-date=2021-04-25|language=en|author=Al Jazeera}}</ref> 
|-
|}

==Operational history==
In 1999–2000, [[Australia–Indonesia relations|relations between Indonesia and Australia]] were tense following a [[1999 East Timorese independence referendum|referendum in East Timor]], in which the East Timorese population voted for independence from Indonesia.

During the hiatus between the announcement of the referendum result and its ratification and withdrawal by Indonesia, an international peacekeeping force for East Timor, named [[INTERFET]], was announced. A [[Royal Australian Navy]] transport vessel, {{HMAS|Kanimbla|L 51|6}}, was to serve as an INTERFET command post. As ''Kanimbla'' approached the coast of East Timor, it entered what were technically still Indonesian waters.

An Indonesian ''Cakra''-class submarine was conducting a routine patrol duties in the [[Timor Sea]], when its sonar detected several unidentified surface ships moving towards [[Dili]]. The submarine's commander directed the ship to submerge to  periscope depth. The unidentified surface ships turned out to be a convoy of three ships: ''Kanimbla'' and two [[Royal New Zealand Navy]] frigates. The submarine captain ordered preparations for the firing of torpedoes.<ref name=idmcakra>{{cite web |url= https://www.indomiliter.com/nyaris-disengat-torpedo-kapal-selam-cakra-class-inilah-profil-hmas-kanimbla/ |title= Nyaris Disengat Torpedo Kapal Selam Cakra Class, Inilah Profil HMAS Kanimbla| first1= Gilang |last1= Perdana |work=indomiliter |date=26 April 2018|access-date=23 September 2020}}</ref>  While the New Zealand frigate crews were aware of the presence of a submarine, they were unable to determine its exact position. At that point, the commander of ''Kanimbla'' communicated with the Australian government regarding the situation, and [[Canberra]] contacted [[Jakarta]] to request permission for the INTERFET vessels to enter Indonesian waters and set course to Dili.<ref name=idmcakra/> The submarine was ordered not to obstruct the convoy. It then surfaced and shadowed the convoy for the rest of its voyage.<ref name=idmcakra/>

=== Sinking of ''Nanggala'' ===
{{further|KRI Nanggala (402)#Sinking}}
On 21 April 2021, the [[Indonesian Navy]] announced that ''Nanggala'', with 53 sailors on board, had failed to report after a [[SUT torpedo]] [[live fire exercise]] in the [[Bali Sea]].<ref name="janes">{{cite news |url= https://www.janes.com/defence-news/news-detail/indonesian-navy-submarine-missing-in-bali-sea |title= Indonesian Navy submarine missing in Bali Sea
| first1= Ridzwan |last1= Rahmat |work=Janes |date=21 April 2021|access-date=21 April 2021}}</ref><ref>{{Cite web|last=Pattisina|first=Edna C|last2=Puttranto|first2=Angger|date=2021-04-21|title=Kapal Selam KRI Nanggala-402 Hilang di Utara Bali|url=https://www.kompas.id/baca/polhuk/2021/04/21/kapal-selam-kri-nanggala-402-hilang/|url-status=live|access-date=2021-04-21|website=kompas.id|archive-url=https://web.archive.org/web/20210421095225/https://www.kompas.id/baca/polhuk/2021/04/21/kapal-selam-kri-nanggala-402-hilang |archive-date=2021-04-21 }}</ref><ref>{{Cite news|date=2021-04-21|title=Indonesian submarine goes missing north of Bali|language=en-GB|work=BBC News|url=https://www.bbc.com/news/world-asia-56829278|access-date=2021-04-21}}</ref> The Indonesian government announced that a search party had been deployed, and that they had requested the assistance of the governments of Singapore and Australia to aid in the search. [[US Navy]] and [[Indian Navy]] also responded. India dispatched its [[DSRV]] from [[Vishakhapatnam]] and [[United States]] stated it was sending airborne assets.<ref>{{Cite web|date=2021-04-21|title=Kapal Selam TNI AL Hilang Kontak saat Latihan di Selat Bali|url=https://www.cnnindonesia.com/nasional/20210421170811-20-632992/kapal-selam-tni-al-hilang-kontak-saat-latihan-di-selat-bali|url-status=live|access-date=2021-04-21|website=[[CNN Indonesia]]|language=id-ID|archive-url=https://web.archive.org/web/20210421102653/https://www.cnnindonesia.com/nasional/20210421170811-20-632992/kapal-selam-tni-al-hilang-kontak-saat-latihan-di-selat-bali |archive-date=2021-04-21 }}</ref>

On 24 April, Indonesia officially declared that the submarine had sunk, following the retrieval of objects believed to have been parts of ''Nanggala'', including a torpedo straightener and prayer mats. "With the authentic evidence we found believed to be from the submarine, we have now moved from the sub miss phase to sub sunk", [[Chief of Staff of the Indonesian Navy|Navy Chief]] [[Yudo Margono]] has said. He also stated that scans have detected the submarine {{convert|850|m|ft}} deep, significantly below the {{convert|500|m|ft}} ''Nanggala'' was able to withstand.<ref name="NanggalaSunk"></ref> On 25 April, ''Nanggala'' was found, split into three parts, and the entire crew of 53 people were confirmed dead. "Based on the evidence, it can be stated that the KRI ''Nanggala'' has sunk and all of its crew have died," [[Indonesian military ranks|Marshal]] [[Hadi Tjahjanto]] told reporters.<ref name="NanggalaFound"></ref>

==See also==
* [[List of active Indonesian Navy ships]] 
* [[Equipment of the Indonesian Navy]]

==References==
{{reflist}}

==Bibliography==
*{{cite book|editor-last1=Gardiner |editor-first1=Robert |editor-last2=Chumbley |editor-first2=Stephen |title=Conway's All the World's Fighting Ships 1947–1995 |year=1995 |publisher=Naval Institute Press |location=Annapolis, Maryland, US |isbn=1-55750-132-7 }}
*{{cite book|editor-last1=Saunders |editor-first1=Stephen |title=Jane's Fighting Ships 2009–2010 |year=2009 |publisher=Jane's Information Group |isbn=9780710628886 }}

{{Cakra-class submarine}}
{{Indonesian Navy active ship classes}}

[[Category:Cakra-class submarines| ]]
[[Category:Type 209 submarines]]
[[Category:Submarines of Indonesia]]
[[Category:Germany–Indonesia relations]]