The Type 214 is a class of diesel–electric submarines developed exclusively for export by Howaldtswerke-Deutsche Werft GmbH (HDW).[1] It features diesel propulsion with an air-independent propulsion (AIP) system using Siemens polymer electrolyte membrane (PEM) hydrogen fuel cells. The class combines the design principles of the Type 209 submarine family and the features of the Type 212A submarine.[1] However, as an export design, it lacks some of the classified technologies of the Type 212 such as the non-magnetic steel hull that makes it difficult to detect using a magnetic anomaly detector.[3]

Type 214 profile
Class overview
Builders
Operators
Preceded byType 209 submarine[1]
Succeeded byType 216 submarine
Subclasses
Cost$330 million (2008)[2]
Built2001–present
In commission2007–present
Planned21
Building5
Completed16
Active15
General characteristics
TypeSubmarine
Displacement
  • 1,690 t (1,660 long tons) (surfaced)
  • 1,860 t (1,830 long tons) (submerged)
Length65 m (213 ft 3 in)
Beam6.3 m (20 ft 8 in)
Draught6 m (19 ft 8 in)
PropulsionDiesel–electric, fuel cell AIP, low-noise skew back propeller
Speed
  • 12 knots (22 km/h; 14 mph) surfaced
  • 20 knots (37 km/h; 23 mph) submerged
Range
  • 12,000 nmi (22,000 km; 14,000 mi) (surfaced)
  • 420 nmi (780 km; 480 mi) at 8 knots (15 km/h; 9.2 mph) (submerged)
  • 1,248 nmi (2,311 km; 1,436 mi) at 4 knots (7.4 km/h; 4.6 mph) (submerged)
Endurance84 days
Test depthnearly 400 m (1,300 ft)
Complement5 officers + 22 crew
Armament

Due to improvements in the pressure hull materials, the Type 214 can dive nearly 400 metres (1,300 ft).[4] It can also carry food, fresh water and fuel for 84 days of operation.

A contract to build four submarines for the Hellenic Navy was signed 15 February 2000 and a fourth unit was ordered in June 2002. The first submarine was built at HDW in Kiel, Germany and the rest at the Hellenic Shipyards Co. in Skaramangas, Greece. The Hellenic Navy named them the Papanikolis class.

The Republic of Korea Navy has ordered nine Type 214 submarines, designated as Son Won-Il class, to be built in Korea by Hyundai Heavy Industries and Daewoo Shipbuilding & Marine Engineering; three first batch models entered service since 2007, and six second batch models entered service from 2012.

General characteristics

edit
  • Displacement: 1,690 t surfaced / 1,860 t submerged
  • Dimensions: length 65 m (213 feet 3 inches ) / beam 6,3 m (20 feet 8 inches) / draught 6 m (19 feet 8 inches)
  • Pressure hull: HY-100[5]
  • Armament: 8 × 533 mm torpedo tubes, 4 subharpoon-capable
  • Propulsion: low noise skew back propeller
  • Diesel engines: 2 × MTU 16V-396 (3.96 MW)
  • Charging generators: 2 × Piller Ntb56.40-10 0.97 MW
  • AIP system: 2 × HDW PEM fuel cell module BZM120 (120 kW × 2)[6]
  • Electric motor: 1 × Siemens Permasyn (2.85 MW)
  • Speed: 10 kn surfaced / 20 kn submerged
  • Speed on fuel cells: 2–6 kn estimated
  • Range surfaced: 19,300 km (12,000 miles)
  • Range submerged: 780 km @ 15 km/h (420 nmi @ 8 kn)
  • Range on fuel cells: 2,310 km @ 7 km/h (1,248 nmi @ 4 kn)
  • Mission endurance: 12 weeks
  • Submerged without snorkelling: 3 weeks
  • Operating depth: more than 250 m (820 feet) officially, 400 m estimated (1312 feet)
  • Complement: 5 officers + 22 crew
  • Navigation radar: SPHINX-D with 4 kW pulse and tactical LPI radar sensor [Thales Deutschland Kiel]

Operators

edit

Current operators

edit

Greece

edit

The Hellenic Navy ordered four Type 214 submarines to be known as the Papanikolis class. The first, Papanikolis, was built in Germany; the following three were scheduled for construction at HDW's Hellenic Shipyards in Greece. In December 2006, StrategyPage reported that Papanikolis was found to have numerous technical problems.[7] Among the reported problems with the submarine were excessive propeller cavitation, overheating of the air-independent propulsion system's fuel cells, and excessive rolling in bad weather when surfaced. Seapower magazine reported the Hellenic Navy refused to accept Papanikolis; additional problems noted were inadequate air-independent propulsion system output power, inappropriate periscope vibration, sonar flank array problems and seawater leakage into the ship's hydraulics.[8]

The Hellenic Navy officers in charge of the testing program at the Kiel shipyards in Germany made their case clear in a 2007 investigative journalism program called "Neoi Fakeloi" on Skai TV (Greece). Retired Rear Admiral M. Simionakis, who had been in charge of the Papanikolis program for the navy, told the interviewer that the manufacturer had made two attempts to fix a severe balance problem in the submarine, including shifting 21 tons of material from the top to the bottom, yet the vessel continued to heel as much as 46 degrees in sea trials. Photographic evidence of the severe heeling was presented. In the same TV program, the officer replacing Simionakis in Kiel, Capt. K. Tziotis, listed seven ongoing, serious problems with the vessel, including balance problems when traveling on the surface, problems with the AIP system, problems with the weapon system, problems with the periscope, and problems with flooding.

 
Greek submarine Papanikolis at the HDW's yard in Kiel, 2008

TKMS, the German shipbuilder of Type 214, had previously asserted that it solved all the boat's technical problems in 2006 and stated that the Greek Navy's continuing complaints about Papanikolis' technical condition are a ploy to justify a price reduction. Therefore, TKMS refused to deliver the boat to the Greek Navy until all debts were paid and Papanikolis remained in Kiel harbor.[9] Despite this position by TKMS, the Hellenic Navy officers in charge of the submarine delivery have repeatedly stated there are problems with Papanikolis. In October 2008, Papanikolis conducted a new round of trials, which showed that the excessive rolling problem had finally been fixed. The rest of the problems are considered solved. According to the Greek defence press, acceptance of the vessel was imminent.[citation needed] The second boat, Pipinos, was officially launched on 6 October 2014 and passed through Greek harbour acceptance trials in Elefsina.

On 21 September 2009, TKMS announced that the contract with the Greek Navy for all four submarines had been cancelled due to country's arrears of more than 520 million Euros. TKMS began seeking arbitration to resolve the matter.[10][11]

On 27 October 2009, the Greek Ministry of Defence confirmed that they intended to accept the three boats built in Greece.[12] The Greek Papanikolis U214 class is equipped with a hoistable radar mast which does not penetrate the pressure hull of the submarine. In the top of the radar mast the radar transmitter is installed. This transmitter is part of the SPHINX Radar System supplied by Thales Defence Deutschland GmbH in Kiel. The radar sensor is a FMCW transceiver which can't be detected by ESM systems in medium terms. This technology is so called LPI radar, which means "Low probability of intercept". The transmitting power is lower than the power of a mobile phone but the resolution more precise compared to high power Pulse radar. Thales SPHINX radar is a tactical radar, designed for submarines. Greece ordered four submarines and paid the list price of six. (2 bn euros)[13]

Portugal

edit
 
NRP Tridente at Lisbon Naval Base, 2010

In 2005 Portugal awarded a contract to Howaldtswerke-Deutsche Werft for two Type 214 submarines, which were delivered in 2010. These two submarines, the NRP Tridente and the NRP Arpão, are the only submarines currently in active service with the Portuguese Navy replacing the Albacora-class submarines in 2010.[14][15] In 2014, the two submarines received new UGM-84G Sub-Harpoon Block II missiles.[16] From 2016 to 2018 the Tridente submarine carried out a major mid-term overhaul at Thyssenkrupp Marine Systems shipyards,[17] and the Arpão submarine, from 2018 to 2021 carried out a major mid-term overhaul at the Portuguese Arsenal do Alfeite shipyards[18][19] The Portuguese Military Programming Law signed in May 2019 aims for the modernization of the two submarines by 2030.[20][21]

South Korea

edit
 
ROKS Son Won-il at Busan Naval Base, 2008

In 1995, the South Korean Navy announced plans to introduce submarines larger than type 209. Later in October 2000, the ministry of defence signed an agreement with Howaldtswerke-Deutsche Werft to introduce type 214 submarines, which also included the transfer of submarine building technology.[22] The South Korean Son Won-Il U214-class submarine (Hangul: 손원일급 잠수함, Hanja: 孫元一級潛水艦) is equipped with a SPHINX-D Radar System supplied by Thales Defence Deutschland GmbH. It uses an additional pulse transmitter in the top of the mast. The combination of high power pulse radar and a very low power LPI transmitter is very effective for submarines. During surface operations, the boat sails with an open pulse fingerprint for ESM systems, but within a secret mission the operator switches to LPI mode. The boat remains invisible to others. Total of 9 are planned and 8 are in active duty. South Korea ordered its first three KSS-II/ Type 214 boats in 2000, which were assembled by Hyundai Heavy Industries. The Batch 2 order will add six more submarines to the Navy, to be built by Daewoo Shipbuilding & Marine Engineering.

In March 2008, it was reported in the media that the first Type 214 submarine of the Republic of Korea Navy suffered from defects related to excessive noise from the screw, according to anonymous sources.[23] Later the ROKN denied the report.[24] There were no further reports of such noise problems in succeeding South Korean Type 214 submarines. The first three Type 214 submarines of South Korea were built by Hyundai Heavy Industries. In August 2008, South Korea signed another contract with HDW for six more Type 214 submarines. The Batch 2 order will add six more submarines to the Navy, to be built by Daewoo Shipbuilding & Marine Engineering. Hong Beom-do, a specialized guided missile submarine was launched on 5 April 2016.[25]

Future operators

edit

Turkey

edit

The first request by the Turkish Naval Forces was made in 2009 and considered to be delivered in 2014. However, due to delay, a new contract was signed in 2016 and first deliveries were planned 2020.[26] The Turkish Navy had commenced negotiations with HDW for six licence-built Type 214 class air-independent propulsion (AIP) submarines. According to the Undersecretary for Defence Industries of the Turkish Government, these submarines would be produced with maximum local content at Gölcük Naval Shipyard in Kocaeli, Turkey. The first submarine in the order initially put to sea in December 2022,[27] the program partially delayed by the COVID-19 pandemic, with the second following in May 2023.[28]

On 2 July 2009, HDW and the Turkish Ministry of Defence entered into an agreement for the licensed production of six platforms. The agreement was the largest defence acquisition project in Turkey at the time after the firm order for 116 F-35 fighters at a cost of in excess of $10 billion. Ankara hoped that its advanced, locally produced and highly modified Type 214 submarines will enter into service by 2015.[29][30][31] Defence Minister Vecdi Gonul stated that "Turkish industrial participation in the project would be worth around 80 percent of the total value of the deal".[32]

As the Turkish Type 214 will have a significant amount of Turkish indigenous systems on board, this variant of the Type 214 will be known as the Type 214TN (Turkish Navy). HDW will preassemble classified elements such as the fuel cells and propulsion system and will then ship them to Turkey. All electronic and weapon systems (including the C4I system) will be of Turkish production.

On 1 July 2011, the 2 billion euros order for six U 214 submarine material packages placed with ThyssenKrupp Marine Systems by Turkey entered into force with receipt of the advance payment. This enabled ThyssenKrupp to begin executing the order. The order was designated to contribute to securing employment at HDW in Kiel, as well as at many subcontractors in Germany and Turkey, for the next ten years. Yet, recently Turkey has received around 2 Million euros compensation from ThyssenKrupp due to delayed manufacturing of the Type214TN.[33] A possible reason for this delay is Turkey's demand for in-house developed software within the submarines. However, Germany refused Greek demands to block delivering six Type 214 submarines to Turkey, as the manufacturer Thyssen was bound by contracts signed since 2002.[34]

Potential operators

edit

India

edit

A larger variant of the Type 214 is being offered to India with the Project 75I, it is in competition against the S-80.[35][36][37] It is possible though that the Type 212CD and the Type 218 are being offered as alternatives. [38]

The French Barracuda-class and the Scorpène-class submarine were disqualified in 2021, and withdrawn in 2022.[39][40] The South-Korean KSS-III submarine (DSME-3000) was also withdrawn.[41] A Russian export Amur-class submarine (Amur-1650) was withdrawn in February 2022 after being disqualified in July 2021.[42]

Failed bids

edit

Indonesia

edit

In the MEF III (Minimum Essential Force) it mentioned the Type 214 submarine from Germany alongside the Scorpène submarine from France. The Indonesian Navy is planning in procuring four to six superior Type 214[43] submarines and two Scorpene submarines.[44]

On 2 March 2021, representatives of the German shipbuilder TKMS began discussions with the Indonesian Ministry of Defense and the Ministry of State Owned Enterprises regarding the procurement of up to four submarines of the Type 214 submarine.[45]

On 2 April 2024, Indonesia only placed an order for two Scorpene submarines but not for the Type-214.[46]

Pakistan

edit

In 2008, the Pakistan Navy entered in negotiation of possibly purchasing three Type 214 to be built in KSEW through a technology transfer, and the HDW CEO Walter Freitag confirming and reportedly telling the news media in Pakistan during the IDEAS 2008 convention that: "The commercial contract has been finalised up to 95 per cent."[47]

It was reported that the first Type 214 diesel–electric submarine would be delivered to the Pakistan Navy in 64 months after signing of the contract while the rest would be completed successively in 12 months.[47][48] After wavering for over two years, Pakistan dropped out from this deal when successfully negotiating with China to develop and design Eight Type 039A submarine that features the AIP technology with a complete transfer of technology to be built in Pakistan.[49]

Vessels by nation

edit
Class No. Ship Laid down Launch Date Comm. Builder
  Hellenic Navy (4 in service, 2 cancelled)
Papanikolis class S-120 HS Papanikolis 27 Feb 2001 22 Apr 2004 2 Nov 2010 HDW
S-121 HS Pipinos Feb 2003 Nov 2006 6 Oct 2014[50] Hellenic Shipyards Co.
S-122 HS Matrozos Mar 2003 Feb 2014[51] 23 Jun 2016[51]
S-123 HS Katsonis Mar 2004 Jun 2015[51] 23 Jun 2016[51]
  Republic of Korea Navy (9 in service)
Sohn Wonyil class

KSS-2

SS-072 ROKS Sohn Won-yil Oct 2002 9 Jun 2006 27 Dec 2007 HHI
SS-073 ROKS Jeong Ji 2004 13 Jun 2007 2 Dec 2008
SS-075 ROKS An Jung-geun 2005 4 Jun 2008 1 Dec 2009
SS-076 ROKS Kim Jwa-jin 2008 13 Aug 2013[52][53] 30 Dec 2014 DSME
SS-077 ROKS Yun Bong-gil 2009 3 Jul 2014[54] 21 Jun 2016 HHI
SS-078 ROKS Yu Gwan-sun 2010 7 May 2015 10 Jul 2017[55] DSME[56]
SS-079 ROKS Hong Beom-do 2011 5 Apr 2016 23 Jan 2018 HHI
SS-081 ROKS Lee Beom-seok 2012 8 Nov 2016 13 May 2019 DSME
SS-082 ROKS Shin Dol-seok 2013 7 Sep 2017 31 Jan 2020 HHI
  Portuguese Navy (2 in service)
Tridente class

U209PN

S-160 NRP Tridente 2005 2010 May 2010 HDW
S-161 NRP Arpão 2005 2010 28 Apr 2011[57]
  Turkish Navy (1 in service, 5 to be delivered)
Reis class S-330 TCG Piri Reis 28 Sep 2015 22 Dec 2019 25 Aug 2024[58] Gölcük Naval Shipyard
S-331 TCG Hızır Reis 2016 23 May 2022[59] 2025[60]
S-332 TCG Murat Reis 25 Feb 2018 8 Jun 2024 2026[60]
S-333 TCG Aydın Reis 4 Nov 2018 2027[59]
S-334 TCG Seydi Ali Reis 22 Dec 2019 2028[59]
S-335 TCG Selman Reis 23 May 2022 2029[59]
  Planned commissionning

See also

edit
Submarines of similar comparison

References

edit
  1. ^ a b c "HDW Class 214 Submarine". thyssenkrupp. Retrieved 7 May 2021.
  2. ^ "Pakistan's 214 Submarines made in Karachi with German help, World politics". Zimbio. Archived from the original on 1 February 2012. Retrieved 27 December 2011.
  3. ^ "Why Germany's Type 214 Submarine Isn't Exactly a 'Stealth Submarine'". The National Interest. 11 May 2020. Retrieved 7 May 2021.
  4. ^ "Type 212". Retrieved 21 October 2006.
  5. ^ Urlich Gabler: Submarine Design, Bernard & Graefe Verlag, ISBN 3-7637-6202-7, s. 151-153
  6. ^ Dr. Albert E. Hammerschmidt(Siemens AG, Erlangen), Fuel Cell Propulsion of Submarines (PDF), archived from the original (PDF) on 16 July 2011
  7. ^ "Type 214 stumbles into Greece". StrategyPage.com. 11 December 2006. Retrieved 30 November 2007.
  8. ^ "Greece refuses delivery of first Type-214 submarine". Seapower. Navy League of the United States. December 2006. Archived from the original on 12 January 2010. Retrieved 30 November 2007.
  9. ^ "TKMS will not deliver the boats until all debts are paid". Segeberger Zeitung. March 2008. Retrieved 31 March 2008. [dead link]
  10. ^ "ThyssenKrupp cancels Greek submarine order". Reuters. 21 September 2009. Archived from the original on 12 October 2009.
  11. ^ "Germany Cancels Submarine Contract with Greece". Defense-update.com. Archived from the original on 31 March 2012. Retrieved 27 December 2011.
  12. ^ "Google Übersetzer" (in German). Retrieved 27 December 2011.
  13. ^ "Πληρώσαμε τα νέα υποβρύχια 50% παραπάνω από τους Τούρκους". 13 February 2011.
  14. ^ "Submarinos". Marinha (in European Portuguese). Retrieved 5 November 2022.
  15. ^ Defensa.com (29 July 2014). "Submarinos Portugueses com mísseis ainda este ano - Noticias Defensa EDIÇÃO BRASIL". Defensa.com (in Spanish). Retrieved 5 November 2022.
  16. ^ Defensa.com (29 July 2014). "Submarinos Portugueses com mísseis ainda este ano - Noticias Defensa EDIÇÃO BRASIL". Defensa.com (in Spanish). Retrieved 5 November 2022.
  17. ^ "Submarino 'Tridente' da Marinha de Portugal será modernizado na Alemanha". Defesa Aérea & Naval (in Brazilian Portuguese). 24 January 2017. Retrieved 5 November 2022.
  18. ^ "Revisão intermédia de um dos submarinos de Portas vai custar 24 milhões". www.jornaldenegocios.pt (in European Portuguese). Retrieved 5 November 2022.
  19. ^ Rodrigues, Pedro. "Manutenção de submarinos em Portugal: Operação de flutuação e saída da doca do Arpão". idD Portugal Defence (in European Portuguese). Retrieved 5 November 2022.
  20. ^ "A Lei de Programação Militar: Programas,Valores e Oportunidades" (PDF). 2021.
  21. ^ "Lei Orgânica n.º 2/2019" (PDF).
  22. ^ "잠수함산업 발전방향에 관한 연구(2)" (PDF). Korea Defense Industry Association. 1 January 2004. Archived from the original (PDF) on 13 June 2023. Retrieved 13 June 2023.
  23. ^ "Newest submarine for Navy is defective". chosun.com. 14 March 2008. Retrieved 14 March 2008.
  24. ^ "알림메세지". navy.mil.kr. Retrieved 3 February 2019.
  25. ^ "South Korea launches guided-missile submarine".
  26. ^ Güngör Uras (29 April 2014). "Torpidoları aldık ama denizaltı yok". Milliyet.
  27. ^ "Turkey's first Reis-class submarine starts sea trials". Janes.com. Retrieved 15 October 2023.
  28. ^ Ozberk, Tayfun (25 May 2023). "Turkish Navy launches the 2nd Reis-class (Type 214TN) AIP submarine". Naval News. Retrieved 15 October 2023.
  29. ^ Turkey Inks Sub Deal With German Consortium[dead link], Defence News, 2 July 2009
  30. ^ Germany, Turkey sign deal to build submarines, Today's Zaman, 3 July 2009
  31. ^ New Type Submarine (AIP) Project Archived 22 July 2011 at the Wayback Machine, Undersecretariat for Defence Industries of the Republic of Turkey
  32. ^ Turkey, Germany ink sub deal, Hurriyet Daily News, 3 July 2009
  33. ^ ThyssenKrupp Marine Systems (1 July 2011). "ThyssenKrupp Marine Systems – Restructuring largely complete / Strategy confirmed by Turkish submarine contract" (Press release). defense-aerospace.com. Retrieved 6 July 2011.
  34. ^ "Germany rejects Greek request to freeze submarine sale to Turkey". Daily Sabah. 29 January 2021.
  35. ^ Philip, Snehesh Alex; ThePrint (4 April 2024). "Indian Navy team in Germany to inspect AIP tech for new submarines, Spain next". ThePrint. Retrieved 4 April 2024.
  36. ^ "India's submarine project battles hurdle amid rising China, Pakistan pressures". India Today. 20 May 2024. Retrieved 21 May 2024.
  37. ^ Peri, Dinakar (5 May 2024). "Field evaluation of bids for Navy's mega submarine deal underway; German govt. to acquire stake in TKMS". The Hindu. ISSN 0971-751X. Retrieved 25 June 2024.
  38. ^ "Germany Offers India New Stealth Submarines". thediplomat.com. 6 May 2016.
  39. ^ "The 4 Submarines Competing For The Indian Navy's P-75I Program". navalnews.com. 14 October 2021.
  40. ^ "Video: Naval Group Proposal for Indian Navy P-75I Submarine Project". navalnews.com. 4 February 2020.
  41. ^ "MADEX 2021: DSME Sheds Light on Submarine Offer to India for P-75I". navalnews.com. 16 June 2021.
  42. ^ "Russia offers Amur class submarines to India". dnaindia.com. 30 November 2010.
  43. ^ "Indonesia, TKMS discuss HDW Class 209, 214 submarines for navy's requirements". Janes.com. Retrieved 23 December 2022.
  44. ^ "Indonesia plans to buy 4 Scorpene submarines and 2 Gowind corvettes". navyrecognition.com. Retrieved 23 December 2022.
  45. ^ Rahmat, Ridzwan (4 March 2021). "TKMS representatives arrive in Jakarta to discuss Type 214 submarines". www.janes.com. Retrieved 7 March 2021.
  46. ^ Inti, Landauro (2 April 2024). "Indonesia buys two submarines from French state-owned Naval Group". Reuters.
  47. ^ a b "Global Naval Forces - News and Defence Headlines - IHS Jane's 360". Retrieved 19 December 2014.
  48. ^ "Satisfied with COAS Gen. Kayani performance: PM Gilani". PakTribune. Retrieved 27 December 2011.
  49. ^ Defense News, 14 March 2011, p. 1
  50. ^ "HS PIPINOS (S-121)". Πολεμικό Ναυτικό - Επίσημη Ιστοσελίδα. Retrieved 27 August 2024.
  51. ^ a b c d navaltoday (24 June 2016). "Hellenic Navy commissions final two Type 214 submarines". Naval Today. Retrieved 27 August 2024.
  52. ^ "SBS 뉴스 :: 리다이렉트 페이지". 13 August 2013. Retrieved 19 December 2014.
  53. ^ "DSME Launches 4th Type 214 1,800-ton SSK Submarine for ROK Navy". 14 August 2013.
  54. ^ "김정은 '고물' 잠수함 허세에…1800톤급 최신예 '윤봉길함' 내달 초 진수 :: 뉴스zum". Archived from the original on 11 January 2016. Retrieved 19 December 2014.
  55. ^ "Navy Takes Delivery of 1,800-Ton Submarine". Chosun Ilbo. 11 July 2017. Retrieved 12 July 2017.
  56. ^ "Kbs News". News.kbs.co.kr. 24 May 2011. Archived from the original on 29 February 2012. Retrieved 27 December 2011.
  57. ^ "Defesa: Submarino "Arpão" chega sábado à Base Naval de Lisboa". Sapo notícias. 28 April 2011. Archived from the original on 30 April 2011. Retrieved 28 April 2011.
  58. ^ "Turkish Navy commissions first Reis-class submarine". Default. 27 August 2024. Retrieved 27 August 2024.
  59. ^ a b c d Ozberk, Tayfun (24 May 2022). "Turkey launches second Reis-class Type 214 AIP submarine". Naval News. Retrieved 27 August 2024.
  60. ^ a b @DefSecAsia2020 (27 August 2024). "Reis-Class Submarine "TCG Piri Reis" Strengthens Turkey's Status as a Mediterranean Maritime Power". Defence Security Asia. Retrieved 27 August 2024.{{cite web}}: CS1 maint: numeric names: authors list (link)
edit