The US developed the world’s first nuclear-powered submarine named USS Nautilus which undertook its first voyage on January 21, 1954. Compared to conventional submarines it practically had an unlimited range and could stay subsurface for great lengths of time because it didn’t have to surface to recharge its batteries. While most submarines were designed to travel primarily on the surface and dive as per requirement, it was the reverse for nuclear powered submarines as they were designed to remain subsurface and only surface occasionally. The incredible range, subsurface endurance and manoeuvrability of nuclear powered submarines revolutionised the naval strategy and tactics. Meanwhile the USSR commissioned its first nuclear submarine in 1958. The US and the USSR launched their first nuclear submarine armed with ballistic nuclear missiles almost simultaneously in 1960. From the Cold War till now, USSR (later on Russian Federation) continued producing nuclear submarines/diesel-electric submarines armed with nuclear warheads.

During the Cold War, the US Navy also developed a nuclear powered submarine that could launch a nuclear ballistic missile which was named Ship Submersible Ballistic Nuclear (SSBN). Its smaller version was the nuclear powered fast attack submarine, built for speed and stealth and named Ship Submersible Nuclear (SSN). It was armed with anti-submarine mines and torpedoes to destroy and deter other submarines and surface ships.

Role during Cold war. Nuclear submarines carried out three primary roles of ‘strategic deterrence patrols’; hunted other submarines; and provided support to special operations as SSN was the ideal platform to transport SEAL teams for inserting and extricating into and out of hostile territory. SSN was also ideal for covertly gathering strategic intelligence, spying on foreign missile tests, fleet manoeuvres, naval war games and coastal activity.

Ship submersible Guided Missile Nuclear. The US has also introduced a new class of submarine, the Guided Missile Submarine (SSGN), which is armed with cruise missiles and is designed to support US covert special-forces operations.

US Nuclear Submarine force level

US currently operates Los Angeles (32 in action), Seawolf (3 in action) and Virginia (17 in action) class of SSNs. The US has 18 Ohio-class submarines, of which 14 are armed with Trident II SSBNs, each capable of carrying 24 Submarine Launched Ballistic Missiles (SLBMs). The older four SSBNs have been converted to SSGN’s, each capable of carrying 154 Tomahawk guided missiles and equipped to support Special Operations. Other roles explored are:

Missile Defence. The future submarine forces should have the ability to be of an integral element of the national missile defense (NMD) and theatre missile defense (TMD) systems.

Power Projection. Being a self-sufficient stealth platform which can operate in forward areas, makes it an ideal system for power projection.

US companies manufacturing nuclear submarines. The Electric Boat Company, formed in 1900 to provide the US Navy, designs for the first functional military submarine, also helped to build the world’s first nuclear submarine in 1952 and is still building nuclear submarines for the US. It takes support from other ship building companies like Huntington Ingalls Industry. However being a very sensitive technology it is not easily offered to other countries except at government to government level.

Russian Nuclear Submarine force level

As recently as 2017, the Russian fleet operated 61 submarines, 75 per cent of which were more than 20 years old which are in the process of being replaces gradually. Submarines remain the backbone of the Russian Navy. Russia has introduced three new classes of submarines- the Borei or Dolgorukiy-class of SSBNs (built by Sevmash); the Yasen-class of SSNs (designed by Malakhit and being constructed by Sevmash) and an improved version of the Kilo-class diesel-electric attack submarine. Dolgorukiy-class submarines are claimed to be fourth generation and at present only three are in service with an additional eight planned to enter service in the near future. Most of the nuclear-powered submarines are on the force level of the Northern Fleet (Arctic) with Severomorsk as the main administrative base of the Northern Fleet. The Pacific Fleet operates a few nuclear submarines and its non-nuclear submarines operate across the Northern, Pacific, Baltic Sea and Black Sea fleets with HQs at Vladivostok. Russia has been helping India closely in its quest for acquiring nuclear submarines.

Force level by 2020s. It is anticipated that by the 2020s the Russian submarine fleet would be touching 50 to include the 11 Boreis; 10 Yasens; 12 improved Kilos; older submarines including earlier model of Kilo class; experimental diesel submarine Petersburg; and upgraded Akula, Oscar and Sierra attack submarines.

Nuclear Submarines with other nations

Apart from US and Russia, four other nations like India, France, China and the UK maintain a nuclear submarine fleet. Many other countries like Pakistan and Brazil would like to have nuclear submarines which apart from their navy acquiring a cutting edge, will also add to their prestige. France and UK have had nuclear submarines for long but China is a later entry and India has recently entered this elitist club with a modest fleet.

China’s Nuclear Submarine Power

Brief details of Chinese nuclear submarines are included as there are shades of conflict situation with India. China’s submarine base is on the southern coast of China’s Hainan Island. The regular presence of nuclearpowered ballistic missile submarines at the strategic base near the resort city of Sanya is frequently reported. This gives China a more reliable “second strike” capability if its land-based nuclear arsenal comes under attack. It took China about six decades to produce a nuclear submarine and join the elite club. Pentagon has recently reported that China now has a “credible” and “viable” sea-based nuclear deterrent.

The incredible range, subsurface endurance and manoeuvrability of nuclear powered submarines revolutionised the naval strategy and tactics. Sea based nuclear platform is one of the three legs of India’s triad of airborne, naval, and landbased platforms as a minimum nuclear deterrent (MND)

SSBN Fleet. US Department of Defense’s 2019 annual report on Chinese military capabilities has confirmed that China has built six Type 094, or Jin-class SSBN. Four of the vessels are known to be operational while another two are being outfitted at the Huludao Shipyard for operational deployment. Jin-class submarines are capable of carrying up to 12 nuclear tipped ballistic missiles with a range of about 7,200 km which would place the US within striking distance from the Western Pacific. Some analysts estimate that the range could be 8,000 km. This is China’s first credible, seabased nuclear deterrent. China reportedly has 76 submarines including conventional submarines. Over the past 15 years, China has constructed twelve nuclear submarines – two SHANG I-class SSNs (Type 093); four SHANG II-class SSNs (Type 093A); and six JIN-class SSBNs (Type 094). Analysts are still not sure if the Chinese are deploying fully armed submarines to maintain a round-the-clock deterrent however US and its allies are reacting as if China has!

India’s Quest for a Sea Based Nuclear Deterrent

Advanced Technology Vessel (ATV) submarine programme was the first baby steps taken by India during 1983 to develop and deploy nuclear submarines to act as India’s sea-based nuclear deterrent. Sea based nuclear platform is one of the three legs of India’s triad of airborne, naval, and landbased platforms as a minimum nuclear deterrent (MND). In order to gain experience in operating nuclear submarines, a Russian Charlie-class nuclear-powered cruise missile submarine was leased from Russia and served in the IN as INS Chakra from 1988 to 1991. In 2012, India again inducted an Akula-II class SSN on a 10-year lease.

INS Arihant. ‘In an era such as this, a credible nuclear deterrent is the need of the hour,’ said Prime Minister Narendra Modi in November 2018 as he announced that India’s first nuclear-powered ballistic missile-carrying submarine (SSBN) had successfully completed its first deterrent patrol armed with nuclear missiles. The success of the INS Arihant, ‘gives a fitting response to those who indulge in nuclear blackmail’, asserted Modi. The Arihant was launched in 2009 and uses a uranium fuelled pressurized light-water reactor to generate 83-MW of electricity with a speed of about twenty-four knots. It is reported that the weapons are stowed in four vertical launch tubes with about 12 K-15 Sagarika nuclear-tipped missiles designed to launch from underwater. Due to India’s doctrine of no first strike, sea based nuclear deterrent is ideally suited for the second strike as they are likely to survive the first strike being submerged in the sea for long periods of time and at undisclosed locations.

India’s sea-based nuclear deterrence will require major weapon upgrade to become fully credible as K-15 missiles have a range of about 700 km which is not adequate for a strategic deterrent. DRDO has developed K-4 Shaurya SLBM with a range of 3,360 km which is expected to enter service in the early 2020s. With the Arihant being armed with K-4 it will finally be able to serve as deterrence against both Pakistan and China. The other drawback is that the arsenal can carry only four missiles thus the subsequent SSBNs will have to have a greater carrying capacity. The K family of SLBMs are being developed to finally have about 6,000 km of range. Pakistan has responded to these developments by testing Babur III submarine-launched cruise missile from a dynamic platform, capable of carrying various types of payloads up to 450 km.

Future Plans. The Navy will need more than one SSBN so that at least a few can rotate on patrols, while others undergo repairs or are used for training. Redundancy is also necessary to this end and as such it is reported that India plans to have a total of six SSBNs with the second one named INS Arighat has already been launched and is expected to be commissioned by 2021. It is presumed that Arighat will have a more powerful reactor to enable it to carry a larger arsenal. In addition, the IN has reported to have already begun construction of two to four more Arihant class submarines of progressively larger configurations. There are also reports of submarine capable version of Nirbhay subsonic cruise missiles with a range of 1,000 km, being at some stage joining the arsenal. It is reported that India is also negotiating for a 10-year lease of a Russian Project 971 Schuka-B (NATO designation Akula II) class vessel at a cost of $3 billion that will be customised and fitted with indigenous communications systems and sensors. It is likely to be named Chakra-III.

Nuclear Base. By 2022, the Indian Navy will complete a nuclear submarine base named INS Varsha, located on the centraleastern coast of India.