A ballistic missile submarine is a submarine capable of deploying submarine-launched ballistic missiles (SLBMs) with nuclear warheads. These submarines became a major weapon system in the Cold War because of their nuclear deterrence capability. They can fire missiles thousands of kilometers from their targets, and acoustic quieting makes them difficult to detect, thus making them a survivable deterrent in the event of a first strike and a key element of the mutual assured destruction policy of nuclear deterrence.
A nuclear submarine is a submarine powered by a nuclear reactor, but not necessarily nuclear-armed. Nuclear submarines have considerable performance advantages over "conventional" submarines. Nuclear propulsion, being completely independent of air, frees the submarine from the need to surface frequently, as is necessary for conventional submarines. The large amount of power generated by a nuclear reactor allows nuclear submarines to operate at high speed for long periods, and the long interval between refuelings grants a range virtually unlimited, making the only limits on voyage times being imposed by such factors as the need to restock food or other consumables.
The Strategic Forces Command (SFC), sometimes called Strategic Nuclear Command, forms part of India's Nuclear Command Authority (NCA). It is responsible for the management and administration of the country's tactical and strategic nuclear weapons stockpile. It was created on 4 January 2003 by the Vajpayee Government. Air Marshal Teja Mohan Asthana became its first commander-in-chief.
The Borei class, alternate transliteration Borey, Russian designation Project 955 Borei and Project 955A Borei-A, are a series of nuclear-powered ballistic missile submarines being constructed by Sevmash for the Russian Navy. The class is projected to replace the Soviet-era Delta III, Delta IV and Typhoon classes in Russian Navy service.
A nuclear triad is a three-pronged military force structure of land-based intercontinental ballistic missiles (ICBMs), submarine-launched ballistic missiles (SLBMs), and strategic bombers with nuclear bombs and missiles. Countries build nuclear triads to eliminate an enemy's ability to destroy a nation's nuclear forces in a first-strike attack, which preserves their own ability to launch a second strike and therefore increases their nuclear deterrence.
Sagarika, also known by the code names K-15 or B-05, is an Indian submarine-launched ballistic missile (SLBM) with a range of 750 kilometres (466 mi) that was designed for retaliatory nuclear strikes. It belongs to the K Missile family and forms a part of India's nuclear triad.
The Arihant-class is a class of Indian nuclear-powered ballistic missile submarines being built for the Indian Navy. They were developed under the ₹900 billion (US$11 billion) Advanced Technology Vessel (ATV) project to design and build nuclear-powered submarines. These vessels are classified as 'strategic strike nuclear submarines' by India.
The Department of Defence Production of the Ministry of Defence is responsible for the indigenous production of equipment used by the Indian Navy and the other armed forces. It comprises the 41 Indian Ordnance Factories under control of the Ordnance Factories Board and eight Defence PSUs: HAL, BEL, BEML, BDL, MDL, GSL, GRSE and Midhani. The present weapon systems of the Indian Navy are:
INS Arihant, designated S2 Strategic Strike Nuclear Submarine, is the lead ship of India's Arihant class of nuclear-powered ballistic missile submarines. The 6,000 tonne vessel was built under the Advanced Technology Vessel (ATV) project at the Ship Building Centre in the port city of Visakhapatnam.
K-4 is a nuclear capable Intermediate-range submarine-launched ballistic missile developed by the Defence Research and Development Organisation of India to arm the Arihant-class submarines. The missile has a maximum range of about 4000 km.
INS Varsha is a new naval base being developed under Project Varsha for the Indian Navy. This base will be the home of the navy's new fleet of nuclear submarines and ships. It was planned to be located within a radius of approximately 200 kilometres from Visakhapatnam, the headquarters of the navy's Eastern Naval Command. Previous news reports suggested that Gangavaram had been the initial site for the new base. The base is now being developed at Rambilli, which is 50 km from Visakhapatnam.
The K family of missiles, is a family of submarine-launched ballistic missiles (SLBM) developed by India to boost its second strike abilities and thus augment its nuclear deterrence. Information about this family of missiles has mostly been kept classified. It is reported that 'K missiles' are faster, lighter and stealthier than their Agni missile counterparts. High Energy Materials Research Laboratory (HEMRL) developed a new formulation of composite propellant that is more efficient and provide greater thrust compare to Agni missile series. The objective behind the development is to make K missile family faster and lighter without compromising on operational range.
INS Arighat is an upgraded variant of the Arihant-class submarine. It is the second nuclear-powered ballistic missile submarine being built by India under the Advanced Technology Vessel (ATV) project to build nuclear submarines at the Ship Building Centre in Visakhapatnam. It has the code name S3.
USHUS is an integrated sonar system developed by the Naval Physical and Oceanographic Laboratory (NPOL) of the Defence Research and Development Organisation (DRDO), India, for use in submarines of the Indian Navy. It is primarily designed to be used in Sindhughosh class submarines, though it is reported to be fitted in the Arihant-class nuclear-powered ballistic missile submarines as well. USHUS is reported to be superior to its Russian equivalents.
The Indian Navy has been focusing on developing indigenous platforms, systems, sensors and weapons as part of the nation's modernisation and expansion of its maritime forces. As of November 2022, the Indian Navy has 45 vessels of various types under construction, including destroyers; frigates; corvettes; conventional-powered and nuclear-powered submarines and various other ship, and plans to build a strong navy of 200 vessels and 500 aircraft by 2050. According to Chief of Naval Staff's statement in December 2020, India has transformed from a buyer's navy to a builder's navy.
The Indian Navy aims to procure new nuclear-powered attack submarines under Project 75 Alpha. The Government of India approved the construction of six of such submarines in February 2015. These will be designed by the Navy's in-house Directorate of Naval Design and built in India at the Shipbuilding Centre at Visakhapatnam. The construction is expected to commence on 2023-24 while the first submarine is expected to enter service in 2032.
K-5 is a submarine-launched ballistic missile under development by Defence Research and Development Organisation of India. The missile has a planned range of around 5,000-6,000 kilometres.
K-6 is an intercontinental submarine-launched ballistic missile under development by Defence Research and Development Organisation of India. The missile has a planned range of around 10,000 to 12,000 kilometres.
The Indian Pressurized Water Reactor-900 (IPWR-900) is a class of pressurized water reactors being designed by Bhabha Atomic Research Centre (BARC) in partnership with Nuclear Power Corporation of India Limited to supplement the Indian three-stage nuclear power programme
Indian Navy 
