TR-1700-class submarine explained

The TR-1700 (Santa Cruz) is a class of diesel-electric patrol submarines built by Thyssen Nordseewerke for the Argentine Navy in the 1980s, with two submarines completed. These ships are amongst the largest submarines built in Germany since World War II and are among the fastest diesel-electric submarines in the world.^[1] ARA San Juan was lost on 17 November 2017, leaving ARA Santa Cruz as the only remaining submarine of this class. As of 2020, the refit of Santa Cruz has been reported cancelled leaving the entire class inactive.^{[2] [3]}

Development

The original 1977 plan called for six boats, two TR-1700s built in Germany by Thyssen Nordseewerke, two in Argentina by Astillero Domecq Garcia, and two smaller TR-1400s also built in Argentina.^[4] The final agreement in 1982 was modified to six TR-1700s, with the last four to be built in Argentina.^[5]

Possible nuclear propulsion

The TR-1700s to be built in Argentina were considered for an upgrade to a nuclear submarine. The use of INVAP's CAREM reactor for that purpose is an 'urban myth,' as such design is inadequate for moving platforms.https://www.hcdn.gob.ar/comisiones/permanentes/cdnacional/reuniones/vt/vtcom.html?id=2700 The nuclear submarine project never came to fruition, despite later attempts to revive it.^[6]

The reasons why INVAP's reactor is inviable stem from a number of reasons.^[7] The main reasons are:

• The reactor was not designed from scratch for moving platforms and relies on the naïve and dangerous concept of "one reactor fits all purposes".
• The design has not considered the dynamic and operational characteristics of the porting platform. This causes problems in the following areas:
  • Thermal problems due to the large diameter of the pellets (7.6mm), which do not allow sudden power ramps, required in a submarine.
  • Wrong type of control rod mechanisms, not adequate for a rolling and pitching vessel. For example, nut-shell control rods would be more appropriate.
  • The continuous movement of the large liquid free-surface inside the reactor, as experienced in vessels of any type (surface or submerged), leave fuel unexposed and, thus, not refrigerated.
  • Steam generators located inside the reactor vessel (instead of outside) increase the diameter of the vessel and thus its weight, unnecessarily, restricting the operational characteristics of the submarine.
  • Inconvenient coupling of various variables due to auto-pressurization.
  • Lack of land prototype on a moving platform (not static). See figure to the right for a Westinghouse prototype for submarines.
  • Numerical simulations for untested designs are not enough, and are only the first step in a series of validations that have to agree with actual experiments. Before offering a reactor as a proposal, any contractor—at their own expense—should perform experiments on moving platforms (water tanks excited to reproduce ship movements) located on land, and demonstrate that they work and agree with the numerical simulations. The reactor should be identical to the reactor proposed to be fitted in a ship or submarine.

Design

The TR-1700 submarine was designed by Thyssen and its features include high underwater speed, endurance (for a diesel submarine), and survivability. The boat's four MTU 16V652MB80 diesel engines, four generators, and Siemens electric motor can propel it at speeds up to 25kn.^{[8] [9]} Eight 120-cell banks of VARTA batteries are installed on each boat.^[10] They have a diving depth of 300m (1,000feet).^[11] Normal endurance of these boats is 30 days with an extended range up to 70 days. These boats are equipped to accept a Deep Submergence Rescue Vehicle (DSRV). Armaments include six bow 533abbr=onNaNabbr=on torpedo tubes and space for 22 torpedoes. The TR-1700 can launch a variety of weapons via its torpedo tubes, such as the wire-guided SST-4 torpedo and the Mark 37C short antisubmarine torpedo. The automatic torpedo reload system can reload sixteen times and reloading the tubes takes 50 seconds.^{[12] [13]}

When it comes to the electronics and systems the TR-1700 has a HSA SINBADS Action Information Organisation and Fire Control System that is combined with a SAGEM plotting table. The radar consists of the Thomson-CSF Calypso and it has a Atlas Elektronik CSU 3/4 and Thomson Sintra DUUX-5 as sonars.

Thyssen proposed the TR1700A for the Australian program.^[14] The proposed design had a reworked pressure hull, was six meters longer, and half a meter wider than the TR-1700s built for Argentina. It lost to the Type 471 from Kockums, an enlarged .

Service

The first two submarines were delivered on schedule in 1984–85. The remaining four built in Argentina were suspended due to the Argentinean economic crisis of the 1980s. In 1996 work completely ceased on ARA Santa Fe at 70% (or 52%) completion while ARA Santiago del Estero was only 30% complete. After attempts to complete and sell the boats to Taiwan failed, they were cannibalized, along with the parts for the fifth and sixth units, to support the continued operations of the first two submarines.^[1]

Santa Cruz received its mid-life modernization at Arsenal de Marinha, Rio de Janeiro Brazil between September 1999 and 2001.^[4] The work involved the replacement of the engines, batteries, and sonar. Her sister boat San Juan entered the Astillero Domecq Garcia shipyard to receive her refit in 2007;^[15] she completed refit in 2013.^[16]

In September 2010, it was revealed that the Ministry of Defense was conducting feasibility studies to decide if ARA Santa Fe (S-43) should be completed. The decision should be made sometime after completing the mid-life modernization of ARA San Juan (S-42). The estimated cost of completing Santa Fe was $60 million.^{[17] [18]}

On 17 November 2017, the ARA San Juan was reported missing; reports of a fire at the time were denied by the Argentine Navy.^{[19] [20]} A year after that, on 17 November 2018, private company Ocean Infinity (appointed by the Argentine Government) announced that they successfully located the wreck, at 900 metres depth and 500 km from Comodoro Rivadavia.^[21]

Boats in class

TR-1700 class construction data

Ship Name	Pennant number	Builder	Completed	Status
	S-41	Thyssen Nordseewerke	18 October 1984	Inactive; envisaged refit cancelled as of 2020.
	S-42	Thyssen Nordseewerke	19 November 1985	Formerly in service with Argentine Navy. Confirmed lost on 23 November 2017; wreck found in Atlantic Ocean on 16 November 2018. Recovery by American team pending naval decision.
ARA Santa Fe	S-43	Astillero Domecq Garcia		Construction suspended - 70% (or 52%) complete^[22] Boat could be completed after feasibility studies. Unknown if sub was cannibalized for parts along with the rest of incomplete members of the class.
ARA Santiago Del Estero	S-44	Astillero Domecq Garcia		Construction suspended - 30% complete and eventually cannibalized for spare parts for active subs.
(none)	S-45	Astillero Domecq Garcia		Construction suspended - Little complete^[23] Components cannibalized for spares
(none)	S-46	Astillero Domecq Garcia		Suspended Components cannibalized for spares

See also

• List of submarine classes in service
  • Type 209 submarine
• Type 214 submarine

Notes

Sources

• Book: Darman . Peter . 2004 . Twenty-first Century Submarines and Warships . Military Handbooks. Rochester . Grange Books . 1-84013-678-2.
• Book: Gardiner . Robert . Chumbley . Stephen . Budzbon . Przemysław . 1995 . Conway's All the World's Fighting Ships 1947–1995 . Annapolis . Naval Institute Press . 1-55750-132-7.
• Book: Miller . David . Jordan . John . 1987 . Modern Submarine Warfare . New York . Military Press . 0-517-64647-1.
• Book: Miller, David . 1989 . Modern Submarines . New York . Prentice Hall Press . Combat Arms . 0-13-589102-7.

Further reading

• Book: Amendolara Bourdette . Ignacio . Guia de los buques de la Armada Argentina 2005–2006 . 2005 . es, en . 9874394005 . Buenos Aires . 2014-09-13 . 2014-09-13 . https://web.archive.org/web/20140913170252/http://www.ipneditores.com.ar/product_info.php?products_id=142 . dead .
• Web site: Retomarían Proyecto de Submarino de Propulsión Nuclear . Sergio Garcia Pedroche . 2010-07-23 . FuerzasAeronavales.com . Fuerzas Aeronavales . es . 16 July 2016 . dead . https://web.archive.org/web/20160816231047/http://www.fuerzasaeronavales.com/?p=2180 . 16 August 2016 .
• Book: Burzaco, Ricardo. Submarinos de la Armada Argentina 1933–2000 . Eugenio B . Buenos Aires . es . 1999. 978-9879676417.

External links

• Santa Cruz-class patrol submarine
• Submarino de ataque (SSK) classe Santa Cruz / TR-1700
• Classe TR-1700

Notes and References

1. Book: Miller, David . The Illustrated Directory of Submarines . Zenith Press . 2002 . 480 . 0-7603-1345-8 .
2. Web site: Estiman que la llegada del próximo submarino operativo para Argentina demoraría de cinco a seis años. 8 September 2020 .
3. Web site: A. Rossi (Argentina): "Argentina tiene que tener una Fuerza Aérea con aviones supersónicos" (2) - Noticias Infodefensa América. 23 December 2020.
4. Web site: Santa Cruz class Patrol submarine . 2008-10-03 . https://web.archive.org/web/20081014135941/http://www.military-today.com/navy/santa_cruz_class.htm . 2008-10-14 . live .
5. News: Farley. Robert. Everything You Need to Know about Argentina's Submarine Force. 23 November 2017. The National Interest. 20 November 2017. en. https://web.archive.org/web/20171124074636/http://nationalinterest.org/blog/the-buzz/everything-you-need-know-about-argentinas-submarine-force-23290. 24 November 2017. live.
6. News: Promete Garré que se construirá un submarino nuclear en el país . La Nación . 2017-11-19 . https://web.archive.org/web/20121226232935/http://www.lanacion.com.ar/1271651-promete-garre-que-se-construira-un-submarino-nuclear-en-el-pais . 2012-12-26 . live .
7. Web site: Versiones Taquigráficas .
8. Book: Watts, Anthony . Jane's Underwater Warfare Systems, 2002-2003 . Jane's Information Group . March 2002 . 629 . 0-7106-2451-4 .
9. Miller and Jordan (1987), p. 160.
10. Miller and Jordan (1987), p. 161.
11. Darman (2004), p. 8.
12. Gardiner, Chumbley and Budzbon (1995), p. 11.
13. Miller (1989), p. 52.
14. Book: Woolner, Derek . Procuring Change: How Kockums was Selected for the Collins Class Submarine . Department of the Parliamentary Library . 18 September 2001 . Canberra . 34 .
15. Web site: The hull of the S-42 ARA San Juan again soldier . 2012-02-24 . https://web.archive.org/web/20120426045410/http://www.elsnorkel.com/2011/09/el-casco-del-s-42-ara-san-juan.html . 2012-04-26 . live .
16. http://www.pagina12.com.ar/diario/sociedad/3-252116-2014-08-03.html El arte de reparar submarinos. p. 12, 3 August 2014
17. http://www.elargentino.com/nota-107992-medios-121-Por-primera-vez-en-la-historia-se-construiran-en-nuestro-pais-submarinos-para-la-Armada.html Por primera vez en la historia se construirán en nuestro país submarinos para la Armada
18. http://www.fuerzasaeronavales.com/?p=2550 "Argentina estudia construir submarino nuclear en astilleros propios". FuerzasAeronavales website, by Sergio Garcia Pedroche, 28/09/2010
19. News: Argentina's navy searches for missing submarine with 44 crew on board. Goñi. Uki. 2017-11-17. The Guardian. 2017-11-17. en-GB. 0261-3077. https://web.archive.org/web/20171117195103/https://www.theguardian.com/world/2017/nov/17/argentinas-navy-searches-for-missing-submarine-with-at-least-40-on-board. 2017-11-17. live.
20. http://www.diariodenautica.com/la-armada-argentina-confirma-que-hubo-una-explosion-en-el-submarino-ara-san-juan La Armada Argentina asegura que, a pesar de la explosión, continuará buscando el submarino San Juan. "diariodenautica.com"
21. https://oceaninfinity.com/locates_ARA_San_Juan Ocean Infinity Locates the Missing Argentinian Submarine, ARA San Juan Latest News, Ocean Infinity website
22. https://web.archive.org/web/20110616061140/http://www.diputados.gov.ar/dependencias/dcomisiones/periodo-122/122-1990.pdf Congreso Nacional: del submarino ARA Santa Fe, el cual se encuentra al 70% de su construcción
23. Book: Wertheim, Eric . Naval Institute Guide to Combat Fleets of the World: Their Ships, Aircraft, and Systems . US Naval Institute Press . 2002 . 1124 . 1-59114-955-X .