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Kalvari-class submarine (2015)

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Kalvari, the maiden vessel of the class, at sea
Class overview
NameKalvari class
BuildersMazagon Dock Limited
Operators Indian Navy
Preceded by
Succeeded byProject 75I-class submarine
Cost
  • 23,652 crore (equivalent to 340 billion or US$4.1 billion in 2023) for six units
  • 3,942 crore (equivalent to 57 billion or US$680 million in 2023) per unit (FY 2016)
In commission2017 – present
Planned9[1][2]
On order3
Completed6
Active5
General characteristics
TypeAttack submarine
Displacement
  • Surfaced: 1,615 tonnes (1,589 long tons)
  • Submerged: 1,775 tonnes (1,747 long tons)
Length67.5 m (221 ft 5 in)[3]
Beam6.2 m (20 ft 4 in)[4]
Height12.3 m (40 ft 4 in)[3]
Draught5.8 m (19 ft 0 in)[4]
Propulsion
  • 4 x MTU 12V 396 SE84 diesel engines[4]
  • 360 x battery cells
  • DRDO PAFC Fuel Cell AIP (expected to be added in Fleet I submarines from September 2025 onwards)
Speed
  • Surfaced: 11 knots (20 km/h; 13 mph)
  • Submerged: 20 knots (37 km/h; 23 mph)
Range
  • 6,500 nmi (12,000 km; 7,500 mi) at 8 kn (15 km/h; 9.2 mph) (surfaced)
  • 550 nmi (1,020 km; 630 mi) at 4 kn (7.4 km/h; 4.6 mph) (submerged)[5]
Endurance50 days[6]
Test depth350 metres (1,150 ft)[7]
Complement
  • 8 officers
  • 35 sailors
Electronic warfare
& decoys
C303/S anti-torpedo countermeasure system[8]
Armament

The Kalvari-class submarines, formally classified as the Project-75 submarines (P-75), is a class of diesel-electric attack submarines operated by the Indian Navy.[9] Currently being constructed by a syndicate of French and Indian shipyards, namely, Naval Group and Mazagon Dock Limited (MDL) respectively, the class is an export derivative of the French-origin Scorpène-class submarine, originally designed by Naval Group.[10]

A namesake of the former Foxtrot-class submarines that the IN operated between 1967 and 2010, the class was originally planned in the late-1990s as an initial phase of a 30-year long naval rearmament roadmap to replace the IN's conventional submarine fleet, namely the Sindhughosh-class and Shishumar-class submarines.[11][10] India's Ministry of Defence (MoD) ordered an introductory batch of six submarines in 2005, at an initially-estimated cost of 13,000 crore (equivalent to 440 billion or US$5.3 billion in 2023); of the ordered six, five are currently in operational service.[12] In addition to the first batch, a proposal for the purchase of three more submarines was approved in 2023, at an estimated cost of 36,000 crore (US$4.3 billion).[13]

First introduced to operational service in 2017, the submarines are currently operated by the IN for a variety of missions, namely, littoral surveillance, intelligence gathering, anti-submarine warfare, anti-surface warfare and minelaying operations.[9]

History

[edit]

Origins

[edit]

In 1997, the Cabinet Committee on Security (CCS), the highest-decision making body of India's Ministry of Defence (MoD), approved a proposal for the purchase of two Type 209/1500 attack submarines (SSK) for the Indian Navy (IN), at a then-estimated cost of INR ₹700 crore.[14] The two examples of the design, originally conceived by the German-based Howaldtswerke-Deutsche Werft, were proposed to be built at Mazagon Dock Shipbuilders Limited (MDL), located in Mumbai, with the assistance of a foreign naval firm in a corroborative role.[14]

In accordance with the scheme, the IN and MDL approached several naval enterprises for assistance; however, the French-based Thomson-CSF (TCSF) was the only firm willing to participate.[14] Two years later, in 1999, the MoD approved a two-phase plan to build 24 submarines over a 30-year period.[14] For the first phase, which called for the construction of SSKs at MDL, two options were proposed: the former option recommending the construction of the Type 209/1500 at MDL with the assistance of TCSF; the latter option recommending the construction of SSKs based on the newer Scorpène submarine design, conceived by the French-based Armaris (later DCNS, now Naval Group).[14]

Ultimately, the IN chose the latter, reasoning that the Scorpène, which had been offered with a provision of technology transfer (TOT), was more advanced than the Type 209/1500.[14] Another reason for choosing the Scorpène design was because of the IN’s interest in acquiring submarine-launched missiles.[14] At the time, the French-designed Exocet, the US-designed Harpoon and the Russian-designed Kalibr were the only such missiles that were commercially obtainable; however, the Harpoon was unavailable to the IN and the Kalibr was incompatible with the Type 209/1500's torpedo tubes.[14] This led to the Exocet being preferred and subsequently, the Scorpène design.[14] It was also thought that the Scorpène design won the deal because of its capability to fire Exocet anti-ship missiles and an agreement on the air-independent propulsion.[15]

Orders

[edit]

Batch-I:
On 6 October 2005, India signed a series of contracts for transfer of technology to construct six submarines at MDL with Armaris, along with the supply of SM39 Exocet missiles manufactured by MBDA. DCN International was designated as the prime contractor in partnership with Navantia. Armaris was responsible for supply of combat systems and technical advisors for construction of submarines at MDL. Valued at a then-total cost of €2.4 billion,[16] the deal included a 30% offset clause and a delivery timeline wherein the six ordered units were to be delivered between 2012 and 2017.[16][17]

Batch-II:
On 10 July 2023, plans for the acquisition of three additional submarines was formally proposed to the Ministry of Defence along with the proposal for the procurement of 26 Rafale M aircraft.[18] On 13 July 2023, Defence Acquisition Council (DAC), headed by the Defence Minisiter Rajnath Singh, of India granted the Acceptance of Necessity (AoN) for the procurement of both 3 Kalvari-class submarines and 26 Rafale M F4 variant aircraft for the Indian Navy.[19]

In December 2023, MDL submitted a bid to construct the three submarines, equipped with higher measures of indigenously-developed technology along with an air-independent propulsion (AIP) module for enhanced underwater endurance.[20] By June 2024, the price negotiation for acquiring 3 additional submarines were in advanced stages. Three submarines would have more than 60% of indigenous content and were expected to cost around 35,000 crore (US$4.2 billion).[21] The entire upgraded combat management system for the Batch II submarines will be indigenously developed by Bharat Electronics Limited. The first submarine shall be delivered after 6 years of contract signing.[22][23][24]

As of 22 October 2024, the deal for additional 3 submarines will get final clearance from the Cabinet Committee on Security soon.[25] As of 2 December 2024, the deal for 3 additional submarines will be positively signed by January 2025.[26]

Construction

[edit]

Batch-I construction timeline

[edit]

2006-07: The steel cutting for the first submarine, the Kalvari, commences on 14 December 2006, with its hull construction beginning on 23 May 2007.[3][27] However, work stalls when public disclosures reveal that the 2005 agreement had omitted the procurement of specific components, including engines, generator and raw materials.[28] The issue prompts the MoD to establish a public entity, the Mazagaon Procured Materials (MPM), to directly procure the aforementioned materials.[29] Protracted negotiations between the MoD and DCNS for the components lead to the additional sanctioning of ₹4,764 crore by the CCS, which further delays the project by two years.[30]

2011: The project suffers another setback following a breach and flooding at MDL’s dockyard in which components, including sections of the already fabricated hull of at least one of the six units, are submerged under seawater; however, the incident is dismissed by the IN as a "minor obstacle".[28]

The launch of the maiden unit, the Kalvari, in 2015

2015: The project suffers further delays when Navantia exits the project.[31] After eight years in construction, Kalvari is finally launched in October 2015 and commences sea trials a year later, on 1 May 2016.[3]

2016: In June, initial plans to purchase ninety-eight Black Shark torpedoes from the Italian-based munitions manufacturer Whitehead Alenia Sistemi Subacquei (WASS) was cancelled in response to corruption allegations against WASS's sister company, AgustaWestland.[32][33] Although alternatives, such as the SeaHake torpedoes from Germany's Atlas Elektronik and the F21 torpedoes France's Naval Group were considered, the MoD resorts to install its existing inventory of older AEG SUT 264 torpedoes on the submarines as a stopgap measure.[34][35]

2017-19: The second unit, the Khanderi, is launched in January 2017, which is soon followed by the commissioning of Kalvari in December 2017.[36] The third and fourth units, the Karanj and the Vela respectively, are launched between January 2018 and May 2019, while Khanderi is commissioned in September 2019.[37][38][39]

2020-21: The fifth unit, the Vagir, is launched in November 2020,[40] while Karanj and Vela are commissioned between March and November 2021, respectively.[41][42]

2022-23: The sixth and final unit of the class, the Vagsheer, is launched in April 2022,[43] which is soon followed by the commissioning of Vagir in January 2023.[44] The same month, India's Naval Materials Research Laboratory (NMRL) and Naval Group reach an agreement to integrate NMRL's locally-developed AIP technology on the six submarines.[45] Vagsheer commences its maiden sea sortie in May 2023, with delivery scheduled for early-2024.[46][47]

2024: The Defence Acquisition Council (DAC) grants an Acceptance of Necessity (AoN) in February 2024 for the purchase of forty-eight heavyweight torpedoes for the submarines under a global tender as a stopgap measure until an indigenous option, supposedly a submarine-launched version of Varunastra torpedo, becomes available.[48][49] On 14 September, Indian Navy commissioned Kalvari Submarine Escape Training Facility, Vinetra, at INS Satavahana, Visakhapatnam to train personnel about escape procedures for a distress situation. The facility was constructed by Larsen & Toubro and is equipped with a five-meter escape tower integrated with an adjacent diving basin.[50][51][52]

2025: Expected integration of DRDO AIP modules on INS Kalvari the first submarine.[53]

Design

[edit]

Hull

[edit]
A silhouette profile of the design's hull, barring air-independent propulsion

The Kalvari class is capable of offensive operations across the entire spectrum of naval warfare including anti-surface warfare, anti-submarine warfare, intelligence gathering, mine laying and area surveillance.[54] It has a length of 67.5 m (221 ft 5 in), height of 12.3 m (40 ft 4 in), overall beam of 6.2 m (20 ft 4 in) and a draught of 5.8 m (19 ft 0 in). It can reach a top speed of 20 knots (37 km/h; 23 mph) when submerged and a maximum speed of 11 knots (20 km/h; 13 mph) when surfaced. Each submarine has a complement of 8 officers and 35 sailors.[55]

The hull, fin and hydroplanes are designed for minimum underwater resistance and all equipment inside the pressure hull is mounted on shock absorbing cradles for enhanced stealth.[3] Special steel was used in its construction which has high tensile strength, capable of withstanding high yield stress and hydro-static force. Each submarine has 60 km (37 mi) of cabling and 11 km (6.8 mi) of piping.[54]

The class displaces 1,615 tonnes (1,589 long tons) when surfaced and 1,775 t (1,747 long tons) when submerged.[56]

Propulsion

[edit]
A visual of the NMRL-design air-independent propulsion module that is to be equipped on the submarines

The submarine is powered by two 1,250kW MAN diesel engines, which are complemented 360 battery cells (750 kg, 1,650 lb each) that powers a Permanently Magnetised Propulsion Motor for extremely-silent underwater operation, thus allowing it have an operational range of around 6,500 nautical miles (12,000 km; 7,500 mi) at 8 knots (15 km/h; 9.2 mph) when surfaced.[4][57][58]

In addition to surfaced operations, the six submarines will be equipped with fuel-cell air-independent propulsion (AIP) modules for extended endurance during submerged operations.[59] The modules, which have been originally designed by India's Naval Materials Research Laboratory (NMRL), are powered by ruggedized phosphoric acid fuel cells (PAFC). They will provide an enhanced submerged endurance of estimated 14 days to the submarines.[59][60] As of 2024, the AIP module is being manufactured in L&T's AM Naik Heavy Engineering Complex in Hazira, Gujarat. After manufacturing, the module will undergo testing in AIP Integration and Testing facility which was inaugurated in July 2024.[53][61]

The six Batch-I submarines are expected to retro-fitted with the AIP modules during their respective mid-life refits, the first of which begins in September 2025, while the three Batch-II submarines that yet to be purchased will be equipped with the AIP modules during the construction phase with technological oversight from Naval Group.[62][63][53]

Armament

[edit]

This class is equipped with six 533 mm (21 in) torpedo tubes for a combination of 18 heavyweight wire-guided German-made Surface and Underwater Target (SUT) torpedoes and SM39 Exocet anti-ship missiles or 30 mines in place of both.[64][65]

Sensors

[edit]

The class is also fitted with mobile C303/S anti-torpedo decoys for self-defence.[33][3] The weapon systems and sensors are integrated with Submarine Tactical Integrated Combat System (SUBTICS). It has a sonar system is capable of Low Frequency Analysis and Ranging (LOFAR) enabling long range detection and classification.[3]

Operational history

[edit]

In June 2023, INS Vagir was deployed on an extended patrol in the Indian Ocean. As a part of the deployment, the submarine reached Colombo, Sri Lanka on 19 June 2023. Then, it covered nearly 7,000 kilometres to reach Fremantle, Australia on 20 August 2023.[66][67] This is the first time that a submarine of this class was on a long-range deployment.[68]

On 24 March 2024, a Kalvari class submarine reached, the Campbell Bay, the southernmost port of India in the Nicobar Islands, for the first time.[69][70]

Three of these submarines were deployed alongside INS Vikrant along with 7 frontline warships and 3 submarines (Shishumar class and Sindhughosh class) on 7 November 2024. The operations included carrier operations of MiG-29K, missile firing drills, submarine manoeuvres and flypasts by 30 aircraft demonstrated to the President of India Droupadi Murmu who was present on board INS Vikrant.[71][72][73]

In an incident on 22nd November 2024, a submarine of the Kalvari class collided with a fishing boat about 70 nautical miles off the coast of Goa. The Navy rescued 11 fishermen before their boat sank. Two fishermen remain missing, with the Navy and Coast Guard deploying various ships to locate them.[74]

Ships of the class

[edit]
Name Pennant Yard Builder Launched Commissioned Homeport Status
Batch-I
Kalvari S21 11875 Mazagon Dock Limited 27 October 2015[3] 14 December 2017[75] Active
Khanderi[76] S22[77] 11876 12 January 2017[78] 28 September 2019[39] Mumbai[58]
Karanj S23 11877[79] 31 January 2018[37] 10 March 2021[80][41][81]
Vela[82] S24 11878[83] 6 May 2019[38] 25 November 2021[42]
Vagir[40] S25 11879[84] 12 November 2020[40] 23 January 2023[44] Mumbai[68]
Vagsheer S26 11880 20 April 2022[43] December 2024 (expected)[85][86] Sea trials[47]
Batch-II
TBD Mazagon Dock Limited To be ordered[18]
TBD
TBD
[edit]

See also

[edit]

References

[edit]
  1. ^ Ghosh, Sanchari (10 July 2023). "PM Modi to ink deal with France to acquire 26 Rafale-M fighters, three attack submarines". The Mint.
  2. ^ "India Drops Plans to Add 3 More French Stealth Attack Submarines". The Diplomat. 8 September 2016. Archived from the original on 8 September 2016.
  3. ^ a b c d e f g h "Curtain Raiser : Kalvari to be Commissioned Tomorrow at Mumbai". pib.nic.in. 13 December 2017. Archived from the original on 14 December 2017. Retrieved 13 December 2017.
  4. ^ a b c d Rahmat, Ridzwan (7 June 2017). "India's second Scorpène submarine begins sea trials". Jane's Defence Weekly. Archived from the original on 28 December 2017.
  5. ^ Commodore Stephen Saunders, ed. (2005). "India". Jane's Fighting Ships 2005-2006 (108th ed.). Coulsdon: Jane's Information Group. p. 308. ISBN 0710626924.
  6. ^ "India, France to ink Scorpene deal". The Times of India. PTI. 27 September 2005. Archived from the original on 30 April 2018.
  7. ^ "Scorpene 1000". DCNS. Archived from the original on 15 September 2014. Retrieved 8 April 2015.
  8. ^ Bedi, Rahul (31 January 2018). "India launches third Scorpène-class submarine". Jane's Defence Weekly. Archived from the original on 5 February 2018.
  9. ^ a b "Kalvari-Class Attack Submarines, India". www.naval-technology.com. 28 October 2021.
  10. ^ a b "Explained: India's Kalvari class of submarines, and its strategic significance". indianexpress.com. 19 November 2020.
  11. ^ "The Indian Navy's Potent Conventional Submarine Capability". www.forbes.com. 1 April 2020.
  12. ^ "The Scorpene deal". frontline.thehindu.com. 7 October 2005.
  13. ^ "Modi in France, Navy gets €10 bn boost as proposal for 26 Rafale-Ms, 3 Scorpenes cleared". theprint.in. 13 July 2023.
  14. ^ a b c d e f g h i "UNDUE FAVOUR TO VENDOR IN ACQUISITION OF SUBMARINES - MINISTRY OF DEFENCE - PUBLIC ACCOUNTS COMMITTEE (2009-10)" (PDF). eparlib.nic.in.
  15. ^ "Exocet Missiles, AIP Swing India Submarine Order". defense-aerospace.com. 13 September 2005. Archived from the original on 12 April 2015. Retrieved 8 April 2015.
  16. ^ a b Mohanty, Deba (2006). "India and France Ink SCORPÈNE Deal". Military Technology. Vol. 30, no. 2. Bonne: Mönch Publishing Group. pp. 34–36. ISSN 0722-3226.
  17. ^ "Envisaging more defence ties". The Hindu Business Line. 20 February 2006. Archived from the original on 30 April 2018.
  18. ^ a b "India Likely To Buy 26 Rafales, 3 Scorpene Subs During PM's France Visit". NDTV. 10 July 2023.
  19. ^ "DAC approves proposals for procurement of 26 Rafale Marine aircraft from France to boost Indian Navy's operational capabilities". Press Information Bureau. 13 July 2023. Retrieved 6 September 2024.
  20. ^ "MDL Submits Bid For Over Rs 20,000 Cr Project To Build 3 New Kalvari Class Submarines". ANI. Business World. 13 December 2023.
  21. ^ Pubby, Manu (24 June 2024). "MDL in advanced talks with Defence Ministry for Rs 35,000 crore Kalvari submarine deal". The Economic Times. ISSN 0013-0389. Retrieved 24 June 2024.
  22. ^ "Indian Navy's new Scorpene submarines to have Made in India 'Heart' by BEL with French architecture: French Naval Group". ANI. 29 July 2024. Retrieved 29 July 2024.
  23. ^ "Rafale-M acquisition to clear final hurdle at DAC today". Hindustan Times. 3 September 2024. Retrieved 3 September 2024.
  24. ^ "Navy plans to finalise deals for submarines, Rafale jets, drones by end of 2024". India Today. 10 September 2024. Retrieved 13 September 2024.
  25. ^ Gupta, Shishir (22 October 2024). "India Launches 4th nuclear-missile submarine". Hindustan Times. Retrieved 22 October 2024.
  26. ^ "Navy Chief Dinesh Kumar Tripathi: Deals for Rafale-M jets, three additional Scorpene submarines in advanced stages". The Hindu. 2 December 2024. ISSN 0971-751X. Retrieved 2 December 2024.
  27. ^ Bhatt, Arunkumar (24 May 2007). "Scorpene construction work begins in Mumbai". The Hindu. Archived from the original on 30 April 2018.
  28. ^ a b "The Unsavoury History of India's Long-Delayed Submarine Augmentation Programme". thewire.in. 25 January 2023.
  29. ^ "Defence ministry's blunder delays Scorpene submarine deal". www.rediff.com. 19 December 2009.
  30. ^ "Govt sanctions additional Rs 4764 crore for submarine project". economictimes.indiatimes.com. 11 August 2010.
  31. ^ "Scorpene submarine project to miss target again as Spanish consultants quit". timesofindia.indiatimes.com. 15 April 2013.
  32. ^ Unnithan, Sandeep (1 June 2016). "Contract for 98 Black Shark torpedoes scrapped, Indian nuclear submarine programme further delayed". India Today. Archived from the original on 15 February 2018.
  33. ^ a b Bedi, Rahul (3 May 2016). "India's first Scorpene boat begins sea trials without primary weapons". IHS Jane's Defence Weekly. Archived from the original on 4 May 2016. Retrieved 5 May 2016.
  34. ^ "Exclusive: Handicapped by red tape, Indian Navy to fit old weapons on brand new submarine". www.indiatoday.in. 23 August 201.
  35. ^ "India Has Alternative For Finmeccanica Torpedoes Says Parrikar". Businessworld.in. 29 May 2016. Archived from the original on 8 October 2016. Retrieved 2 January 2017.
  36. ^ "Scorpene-class submarine likely to be commissioned by November-December". The Economic Times. 14 July 2018.
  37. ^ a b "Third Scorpene submarine 'Karanj' Launched at Mazagon Docks". pib.nic.in. 31 January 2018. Archived from the original on 1 February 2018. Retrieved 31 January 2018.
  38. ^ a b "INS Vela: Indian Navy's 4th Scorpene-class made in India submarine launched". The Financial Express. 6 May 2019. Retrieved 6 May 2019.
  39. ^ a b "Rajnath commissions INS Khanderi attack submarine". The Times of India. 28 September 2019. Retrieved 29 September 2019.
  40. ^ a b c Desk, India com News (12 November 2020). "Indian Navy's Fifth Scorpene-Class Submarine INS Vagir Launched". India News, Breaking News, Entertainment News | India.com. Retrieved 12 November 2020. {{cite web}}: |last= has generic name (help)
  41. ^ a b Sharma, Manasvi Shanker (11 March 2021). "India commissions third Kalvari-class submarine". Janes. Retrieved 14 March 2021.
  42. ^ a b "INS Vela commissioned into Indian Navy in Mumbai". The Times of India. 25 November 2021. ISSN 0971-8257. Retrieved 4 June 2024.
  43. ^ a b "LAUNCH OF SIXTH SCORPENE SUBMARINE 'VAGSHEER' AT MAZAGON DOCK LIMITED (MDL), MUMBAI" (Press release). PIB. 20 April 2022.
  44. ^ a b "INS Vagir, 5th submarine of Kalvari class, commissioned into Indian Navy". www.hindustantimes.com. 23 January 2023.
  45. ^ "DRDO's Fuel Cell-based Air Independent Propulsion system to soon be fitted onboard INS Kalvari, significantly enhancing its submerged endurance". www.naval-group.com. 23 January 2021.
  46. ^ "Last submarine of Kalvari class launched - Vagsheer, Yard-11880.jpg" (Press release). PIB. 19 May 2023.
  47. ^ a b "First sea sortie of sixth scorpene submarine Vaghsheer". Lokmat Times. 19 May 2023.
  48. ^ "Aatmanirbhar Bharat: DAC clears capital acquisition proposals worth Rs 84,560 crore to boost the capabilities of the Armed Forces & Indian Coast Guard". pib.gov.in. Retrieved 18 February 2024.
  49. ^ Krishna Menon, Adithya (18 February 2024). "Indian Navy, Coast Guard To Get 15 Maritime Patrol Aircraft Based On Airbus C-295". Naval News. Retrieved 18 February 2024.
  50. ^ "SUBMARINE ESCAPE TRAINING FACILITY – VINETRA COMMISSIONED IN VISAKHAPATNAM". Press Information Bureau. 14 September 2024. Retrieved 14 September 2024.
  51. ^ "Navy gets escape training facility for Kalvari-class submarines". Hindustan Times. 14 September 2024. Retrieved 14 September 2024.
  52. ^ "Submarine escape training facility 'Vinetra' commissioned at Visakhapatnam". Financialexpress. 14 September 2024. Retrieved 14 September 2024.
  53. ^ a b c Pubby, Manu (7 July 2024). "Indian submarines set for indigenous edge in open seas". The Economic Times. ISSN 0013-0389. Retrieved 8 July 2024.
  54. ^ a b "Maiden Sea Trial of Kalvari – First Scorpene Class Submarine". pib.nic.in. 1 May 2016. Archived from the original on 15 December 2017. Retrieved 15 December 2017.
  55. ^ "Road to development in the 21st century goes through the Indian ocean – Shri Narendra Modi, Prime Minister". pib.nic.in. Archived from the original on 15 December 2017. Retrieved 15 December 2017.
  56. ^ Bedi, Rahul (14 December 2017). "Indian Navy commissions first licence-built Scorpène-class submarine". Jane's Defence Weekly. Archived from the original on 28 December 2017.
  57. ^ "India launches fourth Scorpene / Kalvari-class submarine". www.asiapacificdefensejournal.com. 8 May 2019.
  58. ^ a b "INS Khanderi: All you need to know about India's 2nd Scorpene submarine". The Week. Retrieved 19 September 2024.
  59. ^ a b "DRDO successfully tests its new, air-independent propulsion (AIP), to be fitted in six Scorpenes". www.ajaishukla.com. 10 March 2021.
  60. ^ "Why Navy plan to fit Scorpene subs with made-in-India propulsion tech won't materialise before 2024". theprint.in. 10 February 2023.
  61. ^ "MSN". www.msn.com. Retrieved 11 October 2024.
  62. ^ "Scorpene subs to be retro-fitted with the DRDO's air-independent propulsion (AIP), under Naval Group's oversight". www.ajaishukla.com. 24 January 2023.
  63. ^ "Three New Scorpene Submarines That India Is Buying From France To Get AIP Propulsion As Naval Group Commences Integration". bharatshakti.in. 19 July 2023.
  64. ^ Bonsignore, Luca (2005). ""Carrera": The first real Spanish export-submarine floated". Naval Forces. Vol. 26, no. 1. Aldershot: Monch Publications. p. 135. ISSN 0722-8880. 18 torpedoes and missiles can be carried otherwise 30 mines.
  65. ^ Dominguez, Gabriel (22 September 2017). "MDL delivers first of six Scorpène-class submarines to Indian Navy". Jane's Defence Weekly. Archived from the original on 28 December 2017.
  66. ^ "INS VAGIR ON AN EXTENDED RANGE DEPLOYMENT TO FREMANTLE, AUSTRALIA". PIB (Press release). 19 August 2023.
  67. ^ "Indian naval submarine and Pakistani ship visit Sri Lanka at same time". PIB. 19 June 2023.
  68. ^ a b Philip, Snehesh Alex (19 August 2023). "India's Scorpene submarine carries out its longest deployment, travels 7,000 kms to Australia". ThePrint. Retrieved 2 September 2023.
  69. ^ "A Kalvari class submarine makes history with its inaugural visit to Campbell Bay, the southernmost Port of India in the #Nicobar group of islands". @INHQENC, Twitter. 24 March 2024. Retrieved 31 March 2024.
  70. ^ Sharma, Ritu (26 March 2024). "Outmatched 4:1, Indian Submarine Surfaces Near China Chokepoint; Expert Says 'Woefully Short Of Subs'". Latest Asian, Middle-East, EurAsian, Indian News. Retrieved 31 March 2024.
  71. ^ "President Droupadi Murmu witnesses Indian Navy operations onboard INS Vikrant". The Times of India. 7 November 2024. ISSN 0971-8257. Retrieved 8 November 2024.
  72. ^ "President Murmu witnesses Indian Navy's demonstration on INS Vikrant". India Today. 8 November 2024. Retrieved 8 November 2024.
  73. ^ @ANI (7 November 2024). "Indian Navy today showcased six of its conventional submarines at the capability demonstration to President Draupadi Murmu during her visit to the aircraft carrier INS Vikrant at sea..." (Tweet). Retrieved 8 November 2024 – via Twitter.
  74. ^ "Indian Navy Submarine Collides With Fishing Boat Off Goa, 2 Fishermen Missing". NDTV.com. Retrieved 22 November 2024.
  75. ^ Shukla, Tarun (14 December 2017). "INS Kalvari, India's first Scorpene submarine, commissioned by Narendra Modi". Livemint. Archived from the original on 2 March 2018.
  76. ^ "INS Khanderi: A Scorpene class submarine, handed over to Navy". Jagranjosh.com. 20 September 2019. Retrieved 12 November 2020.
  77. ^ "Submarines Active | Indian Navy". indiannavy.nic.in. Indian Navy. Retrieved 18 October 2019.
  78. ^ "Second Scorpene class submarine Khanderi to be launched on Jan 12". The Economic Times. Archived from the original on 12 January 2017. Retrieved 9 January 2017.
  79. ^ "Third Scorpene-class submarine to be launched". Deccan Herald. 29 January 2018.
  80. ^ "INS Karanj - third Kalvari class Submarine commissioned at Naval Dockyard, Mumbai". PIB. 10 March 2021.
  81. ^ Dominguez, Gabriel; Bedi, Rahul. "Indian Navy commissions third Kalvari (Scorpène)-class submarine". Janes. Retrieved 14 March 2021.
  82. ^ Mahale, Ajeet (31 January 2018). "INS Karanj boosts Navy's firepower". The Hindu. Archived from the original on 1 February 2018. Retrieved 31 January 2018.
  83. ^ "Launch of Fourth Scorpene Class Submarine - Vela". 6 May 2019. Retrieved 15 July 2019.
  84. ^ @navalgroup_IN (12 November 2020). "INS Vagir-fifth Kalvari class submarine in collaboration with navalgroup launched today" (Tweet) – via Twitter.
  85. ^ @Sputnik_India (20 September 2024). "EXCLUSIVE: 7 warships, one submarine to join 🇮🇳 Navy in next 4 months — defence sources to Sputnik India One ship is being built in 🇷🇺Russia, while the rest are being made in India..." (Tweet). Retrieved 22 September 2024 – via Twitter.
  86. ^ "Navy to commission 6th Kalvari-class submarine Vagsheer in December". Hindustan Times. 29 September 2024. Retrieved 29 September 2024.