''Sindhughosh''-class () submarines are diesel-electric

submarine A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or infor ...

s in active service with the

Indian Navy The Indian Navy (IN) (ISO 15919, ISO: ) is the Navy, maritime and Amphibious warfare, amphibious branch of the Indian Armed Forces. The President of India is the Supreme Commander of the Indian Navy. The Chief of the Naval Staff (India), Chief ...

. Their names are in

Sanskrit Sanskrit (; stem form ; nominal singular , ,) is a classical language belonging to the Indo-Aryan languages, Indo-Aryan branch of the Indo-European languages. It arose in northwest South Asia after its predecessor languages had Trans-cultural ...

, but in their Roman-alphabet forms sometimes a final short ''-a'' is dropped. The ''Sindhughosh'' submarines, designated 877EKM, were designed as part of ''Project 877'', and built under a contract between Rosvooruzhenie and the

Ministry of Defence (India) The Ministry of Defence (MoD) or Raksha Mantralay is charged with coordinating and supervising all agencies and functions of the government relating directly to national security and the Indian Armed Forces. The President of India is the cerem ...

. The submarines have a displacement of 3,000 tonnes, a maximum diving depth of 300 meters, top speed of 18

knot A knot is an intentional complication in Rope, cordage which may be practical or decorative, or both. Practical knots are classified by function, including List of hitch knots, hitches, List of bend knots, bends, List of loop knots, loop knots, ...

s, and are able to operate solo for 45 days with a crew of 53. The final unit was the first to be equipped with the

3M-54 Klub The Novator Kalibr (Калибр, caliber), also referred to as 3M54-1 Kalibr, 3M14 Biryuza (Бирюза, turquoise), (NATO reporting name SS-N-27 Sizzler and SS-N-30A) is a family of Russian cruise missiles developed by NPO Novator (OKB-8). It ...

(SS-N-27) antiship cruise missiles with a range of 220 km. As of 2024, three of the submarines (S55, S57, S59) based at INS ''Vajrabahu'', Mumbai, form 12th Submarine Squadron while four of the submarines (S60, S61, S62, S65) based at INS ''Virbahu'', Mumbai, form 11th Submarine Squadron.

Life extension and refit

INS ''Sindhuvijay'' has been upgraded with the hydro acoustical USHUS complex and the CCS-MK radio communications system. On 29 August 2014, the Defence Acquisition Council (DAC) cleared the long-awaited mid-life upgrade of the four Kilo-class submarines, which would be carried out in Indian shipyards and is likely to cost . On 5 November 2014 official sources at HSL said more than 90% of the work has been completed on the seventh submarine of the ''Sindhughosh'' class INS ''Sindhukirti''. Scheduled to re-join the fleet on 31 March 2015, she re-entered service on 23 May. The Indian Navy signed a contract with the Russian shipbuilder

Sevmash JSC PO Sevmash () is a Russia, Russian joint-stock company (JSC) under the Vertical integration, vertically-integrated United Shipbuilding Corporation. The Shipyard, shipbuilding operations of Sevmash is in the port city of Severodvinsk on the Whi ...

to refit and upgrade the existing submarines and to extend their operational life by 35 years. The first submarine, INS ''Sindhukesari'', will be sent for refit starting June 2016. The extensive refit, the value for which is pegged at for a total of four submarines, will not only extend the life of the boats but will also upgrade their combat potential and fitted with Klub land attack cruise missile. It was reported in April 2023 that India would be purchasing over 20 Klub anti-ship cruise missiles worth $120 million. On 4 February 2025, it was reported that the deal has been concluded for cruise missiles for Sindhughosh-class submarines in the presence of the

Defence Secretary A ministry of defence or defense (see spelling differences), also known as a department of defence or defense, is the part of a government responsible for matters of defence and military forces, found in states where the government is divided ...

Rajesh Kumar Singh. In 2015, the naval

exercise Malabar Exercise Malabar is a naval exercise involving the United States, Japan and India as permanent partners. Australia re-joined the exercise in 2020. The annual Malabar exercises includes diverse activities, ranging from fighter combat operations f ...

, between the navies of India and the United States, involved and hunting each other. ''India Today'' reported that ''Sindhudhvaj'' managed to track ''Corpus Christi'' and score a simulated kill without being detected. In December 2015, L&T was chosen by the Russian shipbuilder

to be its Indian partner in the refit project. While the first of the four Kilo class subs will go to the Russian Zvezdochka shipyard for inspection and refit, the remaining three are likely to be modernized at the Kattupalli shipyard. The first of the submarines to be modernized at private yard, a first for India, will go in by 2017, An order for 2-3 more submarines could also be commissioned, depending on ongoing acquisition plans of the Indian Navy. One of the submarine was deployed alongside along with 7 frontline warships and 5 submarines ( and ) on 7 November 2024. The operations included carrier operations of

MiG-29K The Mikoyan MiG-29K (; NATO reporting name: Fulcrum-D) is a Russian all-weather carrier-based multirole fighter aircraft developed by the Mikoyan Design Bureau. The MiG-29K was developed in the late 1980s from the MiG-29M. Mikoyan describe ...

, missile firing drills, submarine manoeuvres and flypasts by 30 aircraft demonstrated to the

President of India The president of India (ISO 15919, ISO: ) is the head of state of the Republic of India. The president is the nominal head of the executive, the first citizen of the country, and the commander-in-chief, supreme commander of the Indian Armed ...

Droupadi Murmu Droupadi Murmu (born Durgi Biranchi Tudu; 20 June 1958) is an Indian politician who has been serving as the president of India since 2022. She won the 2022 Indian presidential election, 2022 presidential election as the Bharatiya Janata Party ...

who was present on board INS ''Vikrant''.

Incidents

*On 10 January 2008, INS ''Sindhughosh'' collided with the cargo ship MV ''Leeds Castle''. The submarine was reported to have sustained superficial damage to its

conning tower A conning tower is a raised platform on a ship or submarine, often armoured, from which an officer in charge can conn (nautical), conn (conduct or control) the vessel, controlling movements of the ship by giving orders to those responsible for t ...

. As a result, the submarine was out of service for a month. The cargo ship was in restricted shallow waters. *On 26 February 2010, a fire on board INS ''Sindhurakshak'' killed one sailor and injured two others. The fire was due to a defective battery. *On 14 August 2013 an explosion, followed by a fire, was reported to have occurred on ''Sindhurakshak''. ''Sindhurakshak'' sank in the dock. *On 17 January 2014, ''Sindhughosh'' ran aground due to the low tide, while returning to the Naval Dockyard, Mumbai. *On 26 February 2014, smoke was detected on board INS ''Sindhuratna'' resulting in 7 sailors being rendered unconscious and two dead. Those unconscious were airlifted to hospital.

Ships of the class

Gallery

Image:INS Sindhurakshak (S63).jpg, INS ''Sindhurakshak'' Image:Ins S62.jpg, INS ''Sindhuvijay'' Image:INS_Sindhurakshak_(S63)-1edited.jpg, INS ''Sindhurakshak'' at

Portsmouth Harbour Portsmouth Harbour is a / biological Site of Special Scientific Interest between Portsmouth and Gosport in Hampshire. It is a Ramsar site and a Special Protection Area. It is a large natural harbour in Hampshire, England. Geographically it ...

, UK in 2013 Image:Kilo class SS.svg, design of submarines

References

External links