Project 77-class submarine

{{Short description|Indian class of nuclear-powered attack submarines under development}} {{Use dmy dates|date=July 2019}} {{Use Indian English|date=December 2020}} {{For|the conventional-attack submarine programme|Project 75I-class submarine}} {{Infobox ship |section1={{Infobox ship/image | image = | image_caption = }}

|section2={{Infobox ship/class overview | name = '''Project 77''' | builders = * Ship Building Centre, Visakhapatnam * Larsen & Toubro<ref>{{cite news |last1=Kumari |first1=Khushboo |title=L&T in focus : India clears two nuclear-powered attack submarines armed with supersonic, hypersonic missiles |url=https://www.financialexpress.com/business/industry-lampt-in-focus-india-clears-two-nuclear-powered-attack-submarines-armed-with-supersonic-hypersonic-missiles-3906761/ |access-date=9 July 2025 |publisher=financialexpress.com |date=8 July 2025}}</ref> | operators = {{navy|India}} (Planned) | class_after = | in_commission_range = 2036 (planned) | total_ships_building = | total_ships_planned = *2 cleared *6 planned | total_ships_completed = | total_ships_active = 0 | total_ships_laid_up = | cost = *{{INRConvert|1.2|lc|lk=lc|year=2020}} total cost<ref name="ETfeb2020"/> *{{INRConvert|40000|c||year=2024}} for two (includes cost for establishing, infrastructure, equipments & associated machineries for new class of SSN). }}

|section3={{Infobox ship/characteristics | hide_header = | header_caption = | type = Nuclear attack submarine | displacement = {{convert|10,000|t|lk=on}} | length = | beam = | height = | draft = | depth = | decks = | deck_clearance = | power = | propulsion = * 1 × CLWR-B2 (Compact light-water reactor) {{cvt|200|MW|HP}}<ref name=":2" /> *{{cvt|35|MW|HP}} Nuclear-Electric Propulsion (NEP) Turbine–electric powertrain<ref>{{cite news |last1=Potluri |first1=Parthu |title=Project-77: An Analysis of the Indian Navy’s Nuclear Attack Submarine Program |url=https://www.strategicfront.org/project-77-an-analysis-of-the-indian-navys-nuclear-attack-submarine-program/ |access-date=26 August 2025 |publisher=www.strategicfront.org |date=26 November 2024}}</ref> * 1 × single shaft pump-jet propulsor | speed = | range = Unlimited except by food supplies | endurance = | test_depth = | complement = | time_to_activate = | sensors = | EW = | armament = Varunastra heavyweight torpedo, Electronic Heavy Weight Torpedo Takshak (EHWT) , Nirbhay, BrahMos and BrahMos-II land-attack/anti-ship cruise missiles | notes = }} }}

'''Project 77''' is an Indian Navy acquisition programme to procure nuclear-powered attack submarines.

==Background== {{Excerpt|Project 76 submarine|Background|bold=yes|links=yes}}

== Development == The Government of India, through the Cabinet Committee on Security (CCS), approved the construction of six nuclear attack submarines on 18 February 2015. Following the approval, the Naval Staff Qualitative Requirements (NSQR) are to be ascertained for the over 6,000 tonne-displacement submarines. These are to be built at the Ship Building Centre at Visakhapatnam.<ref name=":1">{{cite news |date=18 February 2015 |title=Government clears construction of 7 stealth frigates, 6 nuclear-powered attack submarines |url=https://economictimes.indiatimes.com/news/politics-and-nation/government-clears-construction-of-7-stealth-frigates-6-nuclear-powered-attack-submarines/articleshow/46282586.cms?from=mdr |access-date=19 April 2015 |newspaper=The Economic Times}}</ref> On 8 December 2017, Navy chief, Admiral Sunil Lanba, announced that the design for the class of six submarines had commenced at the newly commissioned Submarine Design Centre, Gurgaon. The project cost was estimated at {{INRConvert|60000|c|lk=on|year=2017}}.<ref name=":3">{{cite news |last1=Unnithan |first1=Sandeep |date=10 December 2017 |title=A peek into India's top secret and costliest defence project, nuclear submarines |url=https://www.indiatoday.in/magazine/the-big-story/story/20171218-india-ballistic-missile-submarine-k-6-submarine-launched-drdo-1102085-2017-12-10 |url-status=live |archive-url=https://web.archive.org/web/20190420153439/https://www.indiatoday.in/magazine/the-big-story/story/20171218-india-ballistic-missile-submarine-k-6-submarine-launched-drdo-1102085-2017-12-10 |archive-date=20 April 2019 |work=India Today |language=en}}</ref> These will be designed by the Navy's in-house Directorate of Naval Design (now Warship Design Bureau). The construction was expected to commence on 2023–24 while the first submarine is expected to enter service in 2032.<ref>{{Cite web |date=2024-08-31 |title=INS Arighaat: How a second nuclear submarine boosts India’s strategic reach |url=https://www.indiatoday.in/india/story/ins-arighaat-how-a-second-nuclear-submarine-boosts-indias-strategic-reach-2591300-2024-08-31 |access-date=2025-07-21 |website=India Today |language=en}}</ref>

On 24 June 2019, it was reported that {{INRConvert|100|c}} have been allocated for the initial phase of the project. The development is expected to continue till 2025. Mishra Dhatu Nigam is developing a new hull material that is expected to allow the submarine to dive to deeper depths than {{sclass|Arihant|submarine|4}}. A scaled down model of the submarine is planned to be tested first. The total cost of the project is now estimated to be around {{INRConvert|1|lc|lk=on|year=2020}}.<ref>{{Cite news|url=https://economictimes.indiatimes.com/news/defence/work-begins-on-indias-next-gen-nuclear-powered-submarines/articleshow/69921014.cms|title=Work begins on India's next gen nuclear-powered submarines|last=Pubby|first=Manu|date=2019-06-24|work=The Economic Times|access-date=2019-07-02|url-status=live|archive-url=https://web.archive.org/web/20190624164324/https://economictimes.indiatimes.com/news/defence/work-begins-on-indias-next-gen-nuclear-powered-submarines/articleshow/69921014.cms|archive-date=24 June 2019}}</ref>

In February 2020, ''The Economic Times'' reported that the preliminary design phase of the programme has been successfully completed. The report stated that Submarine Design Group of the Directorate of Naval Design, assisted by the DRDO, will now start working on the detailed design and construction phase of the programme.<ref name="ETfeb2020">{{Cite news|last=Pubby|first=Manu|url=https://economictimes.indiatimes.com/news/defence/indias-rs-1-2-l-cr-n-submarine-project-closer-to-realisation/articleshow/74234776.cms|title=India's Rs 1.2 lakh crore nuclear submarine project closer to realisation|date=2020-02-21|work=The Economic Times|access-date=2020-02-23}}</ref>

As of March 2021, it was reported that the Indian Navy has prioritised the construction of Project 75 Alpha submarines over a planned third aircraft carrier.<ref>{{Cite news|last=Gupta|first=Shishir|date=2021-03-24|title=For Navy, 6 nuclear-powered submarines take priority over 3rd aircraft carrier|url=https://www.hindustantimes.com/india-news/for-navy-6-nuclear-powered-submarines-take-priority-over-3rd-aircraft-carrier-101616564522467.html|newspaper=The Hindustan Times|access-date=2021-04-02}}</ref> Later it was announced that initially, three submarines will be cleared in 2023-24 while the remaining three will get clearance later. The first boat was expected to roll out in 2032.<ref>{{Cite news| date=2023-03-18|title=Project-77 (formerly Project-75 Alpha): India may reduce number of SSN to 3, from planned 6 initially|url=https://theigmp.org/project-77-project-75-alpha-india-may-reduce-ssn-number/|website=IgMp|access-date=2023-03-19}}</ref><ref>{{Cite news|last=Pandit|first=Rajat|date=2021-03-31|title=Project to build N-powered attack subs set to get CCS nod|url=https://timesofindia.indiatimes.com/india/project-to-build-n-powered-attack-subs-set-to-get-ccs-nod/articleshow/81770216.cms|newspaper=The Times of India|access-date=2021-04-02}}</ref> The ship class will have a final design clearance in Gurugram by Submarine Design Group, its nuclear reactor will be built in Kalpakkam, hull fabrication will be undertaken by Larsen & Toubro at Hazira and finally assembly and sea trials will be conducted by the Ship Building Centre (SBC) in Visakhapatnam.<ref name="Sharks">{{Cite news|last=Unnithan|first=Sandeep|date=2021-04-17|title=India's nuclear sharks|url=https://www.indiatoday.in/magazine/defence/story/20210426-india-s-nuclear-sharks-1791817-2021-04-17|newspaper=India Today|location=New Delhi|access-date=2021-05-21}}</ref>

As of August 2024, a report suggested that the first batch of P-75A class will have 2 submarines, while 4 more will be cleared in a later phase. The final clearance for the 1st batch worth {{INRConvert|40000|c}} is expected to be received "soon" from the Cabinet Committee on Security (CCS).<ref>{{Cite news |date=2024-08-11 |title=India 'fully ready' to add to fleet 2nd submarine with nuclear-tipped missiles |url=https://timesofindia.indiatimes.com/india/india-fully-ready-to-add-to-fleet-2nd-sub-with-n-tipped-missiles/articleshow/112433199.cms |access-date=2024-08-11 |work=The Times of India |issn=0971-8257}}</ref><ref>{{Cite news |date=2024-08-11 |title=India set to commission its second nuclear-missile submarine |url=https://economictimes.indiatimes.com/news/defence/india-set-to-commission-its-second-nuclear-missile-submarine/articleshow/112438432.cms?from=mdr |access-date=2024-08-12 |work=The Economic Times |issn=0013-0389}}</ref>

On 9 October 2024, the CCS cleared the project at {{INRConvert|40000|c|lk=|year=2024}} to construct 2 nuclear attack submarines for the Indian Navy. The submarines shall be built at Ship Building Centre in Visakhapatnam and will include major private sector firms including Larsen & Toubro.<ref name=":0">{{Cite web |date=2024-10-09 |title=Centre clears deal to build 2 nuclear submarines, purchase 31 predator drones |url=https://www.indiatoday.in/india/story/nuclear-submarine-deal-centre-31-us-predator-drone-indian-army-navy-2614341-2024-10-09 |access-date=2024-10-10 |website=India Today |language=en}}</ref> According to reports, the first submarine will take 10–12 years to be launched with a 190 MW pressurised light-water reactor and a displacement of almost 10,000-tonnes. The maximum speed will be over {{Convert|30|kn|abbr=on}}. The submarines will feature an indigenous content of 95% and foreign assistance will include design consultancy only.<ref>{{Cite news |date=2024-10-09 |title=India clears two mega defence projects for 2 indigenous nuclear submarines & 31 Predator drones |url=https://timesofindia.indiatimes.com/india/india-clears-two-mega-defence-projects-for-2-indigenous-nuclear-submarines-31-predator-drones/articleshow/114095147.cms |access-date=2024-10-12 |work=The Times of India |issn=0971-8257}}</ref><ref>{{Cite news |date=2024-10-14 |title=Navy setting up base to control submarines on long-range patrols |url=https://timesofindia.indiatimes.com/india/navy-sets-up-base-to-control-submarines-on-long-range-patrols/articleshow/114196990.cms |access-date=2024-10-14 |work=The Times of India |issn=0971-8257}}</ref><ref name=":0" />

During a press conference, the Indian Navy confirmed that it plans to operate 6 SSNs in total. The first of the initial two submarines is to be completed by 2036-37 followed by the next in 2038-39.<ref>{{Cite news |last= |first= |date=2024-12-02 |title=Navy Chief Dinesh Kumar Tripathi: Deals for Rafale-M jets, three additional Scorpene submarines in advanced stages |url=https://www.thehindu.com/news/national/deals-for-rafale-m-jets-three-additional-scorpene-submarines-in-advanced-stages-navy-chief/article68937239.ece/ |access-date=2024-12-02 |work=The Hindu |language=en-IN |issn=0971-751X}}</ref><ref>{{Cite web |last=Philip |first=Snehesh Alex |date=2024-12-02 |title=Navy chief spells out mega nuclear attack submarine plan. Here's what it is |url=https://theprint.in/defence/navy-chief-spells-out-mega-nuclear-attack-submarine-plan-heres-what-it-is/2383199/ |access-date=2024-12-02 |website=ThePrint |language=en-US}}</ref><ref>{{Cite news |last=Peri |first=Dinakar |date=2024-12-07 |title=Indigenous nuclear attack submarine design to take 4-5 years, another five years for construction |url=https://www.thehindu.com/news/national/indigenous-nuclear-attack-submarine-design-to-take-4-5-years-another-five-years-for-construction/article68959614.ece/ |access-date=2024-12-08 |work=The Hindu |language=en-IN |issn=0971-751X}}</ref> The submarines are anticipated to be equipped with DRDO-developed hypersonic missiles and an upgraded BrahMos, which might have a strike range of 1,500–2,000 kilometers.<ref>{{Cite web |last=Kumari |first=Khushboo |date=2025-07-08 |title=L&T in focus {{!}} India clears two nuclear-powered attack submarines armed with supersonic, hypersonic missiles |url=https://www.financialexpress.com/business/industry-lampt-in-focus-india-clears-two-nuclear-powered-attack-submarines-armed-with-supersonic-hypersonic-missiles-3906761/ |access-date=2025-07-09 |website=The Financial Express |language=en}}</ref><ref>{{Cite web |date=2026-02-21 |title=Indian Navy Project-77 SSN to get 2,500 km range Hypersonic SLCM to expand its firepower |url=https://igmp.in/indian-navy-project-77-ssn-to-get-2500-km-range-hypersonic-slcm/ |access-date=2026-02-22 |website=India's growing Military power - IgMp |language=en}}</ref>

In September 2025, the ''Times of India'' reported that the Bhabha Atomic Research Centre (BARC) is developing a 200 MWe-rated nuclear reactor for the Indian Navy's next-generation nuclear submarines, including Project 77 and S5-class submarines.<ref name=":2">{{Cite news |title=Bhabha Atomic Research Centre making reactor for Navy's next-generation nuclear-submarines |url=https://timesofindia.indiatimes.com/india/bhabha-atomic-research-centre-making-reactor-for-navys-next-generation-nuclear-submarines/articleshow/124005864.cms |access-date=2025-09-20 |work=The Times of India |issn=0971-8257}}</ref>

==References== {{Reflist|2}}

Category:Nuclear-powered submarines Category:Submarine classes Category:Attack submarines Category:Submarines of the Indian Navy