On November 5, India’s first indigenous SSBN (ship-submersible, ballistic, nuclear) INS Arihant concluded its first, month-long deterrence patrol, prompting Prime Minister Narendra Modi to tweet: “In an era such as this, a credible nuclear deterrence is the need of the hour. The success of INS Arihant gives a fitting response to those who indulge in nuclear blackmail.”
The INS Arihant is a 6,000-tonne submarine, 110 metres long and 11 metres wide that can dive to depths of 300 metres.
It is the first SSBN to have been built by a country other than one of the five permanent members of the United Nations Security Council. Having an SSBN completes the triangle of atomic weapons’ delivery systems comprising strategic bombers, intercontinental ballistic missiles and submarine-launched ballistic missiles (SLBM).
The special quality of an SSBN, as compared to a conventional SSK submarine, is its ability to remain undetected under water for long periods. An SSBN is powered by a nuclear reactor and can remain submerged for months without having to return to base. SSBNs are also different from nuclear-powered attack submarines because they can carry ballistic missiles with nuclear warheads.
The achievement may deserve a pat on the back, but in the absence of a long-range SLBM, the submarine’s predatory potential while lurking at the bottom of the ocean is limited.
The Arihant can carry up to 12 K-15 short-range ballistic missiles, which have an estimated range of about 700 kilometres, or four K-4 intermediate-range ballistic missiles, which have an estimated range of 3,500km. Both missiles are nuclear-capable. It is reported that a second SSBN has completed sea trials. Named Arighat, the sub is due to be delivered next year. It is reportedly larger than Arihant with a complement of eight K-4 missiles instead of four. Two more subs are planned after Arighat, to be commissioned by 2023. India has been mostly silent on the progress in development of SLBMs.
A variant of the Sagarika missile that arms the Arihant is estimated to have a range of 750km. But if it is the threat from China that is in India’s immediate sights, then it has a long way to go as Chinese JL-2 missiles that arm its Jin-class SSBNs are said to have a range of over 6,400km.
The lack of long-range intercontinental SLBMs would mean the SSBN will need to get closer to their target area, exposing it to the danger of detection. The speed of the Indian arms development vis a vis China also leaves a lot to be desired. While it took India two decades to build its first SLBM, China in the same time is known to have inducted 10 nuclear-powered submarines into its fleet and is reportedly building an even bigger and more sophisticated fleet.
In the three decades since it tested its first nuclear-capable ballistic missile, India’s Agni V, according to its own estimates, has achieved a range of 5,000km, although Chinese authorities estimate its range at 8,000km. At a time when there is a jostling for influence in the oceans, the induction of the SLBMs offers a credible deterrent for India, but as of now it is a work in progress.