Why India Needs Both Nuclear and Conventional Submarines

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Why India Needs Both Nuclear and Conventional Submarines

In an Indian context, an all-nuclear submarine force is an essentially flawed idea.

Why India Needs Both Nuclear and Conventional Submarines
Credit: REUTERS/Shailesh Andrade

Last week, the Kalvari, India’s first indigenous stealth submarine’s sea trials outside Mumbai Harbour created considerable excitement in India’s maritime circles. The Kalvari is the first of India’s six submarines based on the Scorpene-class being built under the much-delayed Project 75. Its sail-around was widely seen as an important step forward in meeting the September 2016 target for the submarine’s commissioning.

Despite the absence of its “primary weapon” – the heavyweight “Black-Shark” torpedoes – the Kalvari’s presence in the open seas emphasized India’s efforts at rejuvenating its indigenous submarine production program. While the project has faced long delays, Indian naval technicians and project managers have worked tirelessly to meet construction deadlines. The Kalvari’s appearance in the open seas last week then created new hope for India’s submarine ambitions.

The cheery tidings aren’t limited to the conventional submarine program. Indian maritime watchers are pleased with the impending induction of the first indigenous nuclear-powered submarine, the Arihant. Having cleared its diving trials and missile tests, the Arihant could soon be commissioned into the naval fleet as India’s first nuclear ballistic missile platform (SSBN). At 6000 tons displacement, the new submarine is a unique technology demonstrator and showcases the best of Indian naval design capability. Even though it draws heavily from Russian technology and has a limited ballistic missile capability (its twelve indigenous K-15 Sagarika missiles have a range of only 700 kilometers) the Arihant’s commissioning is a milestone for Indian designers who have worked tirelessly for years to refine procedures for the submarine’s construction.

Needless to say, the prospects of the induction this year of two submarines – one conventional, the other nuclear ballistic – has caused a fair bit of curiosity about the Indian Navy’s proposed submarine force structure, particularly in the wake of reports that India has been exploring the possibility of manufacturing nuclear attack (SSNs) submarines. At an international seminar in New Delhi recently, a participant wondered why the navy was continuing with its dependence on conventional submarines when most advanced navies had shifted to all-nuclear submarine forces.

Indeed, there has been a long-running debate within the Indian Navy about the inherent attributes of an all-nuclear undersea arsenal. Notwithstanding the distinct advantages that nuclear submarines (SSNs) enjoy over conventional subs (SSKs), however, an all-nuclear submarine force, in an Indian context, is an essentially flawed idea. This is because a conventional submarine offers benefits in littoral waters that more than adequately offset its most glaring constraint –limited operating endurance. A diesel electric sub’s biggest advantage is that it is smaller hull that is easier to maneuver in shallow waters and harder to detect. The fact that it costs a fraction of price of a typical nuclear sub, makes a diesel electric an irresistible proposition for a midsize navy. Its attractiveness is only enhanced by the ease of operation and the absence of the risk of dangerous nuclear leaks. Simply put, developing maritime states like India cannot afford to overlook the practical utility and effectiveness of an SSK in South Asia’s littoral spaces.

That said, nuclear submarines confer an edge to a fighting force that diesel electrics find difficult to match. The fact that SSNs are bigger, tougher, more heavily armed and longer-ranged than conventional subs makes them indispensable assets. They can also perform functions that diesel-electric subs generally cannot – like cross an ocean underwater and at high speed or remain submerged for weeks outside critical littoral spaces. The powerful weapons and sensors they host far outweigh the combat capabilities of conventional submarines.

In 1999, when the Indian Navy first proposed a 30-year plan for the construction of 24 submarines, it did not intend to build nuclear attack submarines. At the time, the plan was to construct six submarines each with Western- and Eastern-stream technology in the initial phase, before developing 12 conventional submarines of an indigenous design. Unfortunately, for New Delhi, the plan failed to take off as intended. Many factors have been blamed for this lack of success in implementation: the apparent lack of funds, strong divisions in the navy over a proposal for a mix of conventional and nuclear submarines, and the apparent absence of visionary leadership. Whatever the reasons for its initial failure, New Delhi is now making up for lost time and opportunity by combining its ongoing construction of conventional submarines with a proposal to build six nuclear attack submarines.

Notably, barring some top-tier navies such as the U.S. Navy, Royal Navy and French Navy, no other submarine operating force has completely done away with conventional subs. While the simple advantages of SSKs like ease and quietness of operation have been factors of interest, the past few years have seen technological advances that have helped diesel electrics overcome their traditional disadvantage of less time submerged before surfacing to charge batteries. Air independent propulsion technology and fuel cells have made it possible for conventional submarines to remain underwater much longer that previously.

Not surprisingly then, navies today prefer a combination of nuclear and conventional submarines, with each class playing a specific role. Increasingly modern maritime forces deploy advanced non-nuclear subs like the German Type 214 for sensitive operations. Some European navies, like the Norwegian Navy, have prioritized procurement of non-nuclear submarines to carry out specific tasks, such as protecting the Arctic’s fringes. Unsurprisingly, there have been offers to partner the Indian Navy in developing the design of the new class of nuclear-powered attack submarines. The U.S. has made an expression of interest, though New Delhi is said to have its eyes set on the new Barracuda-class SSN being developed by the French firm DCNS. Following reports that New Delhi has approached Moscow for the lease of a second Akula-class (after the INS Chakra), there is also speculation of another collaborative venture with Russia for the construction of SSNs.

India’s choice of partners for its tactical submarines, however, is independent of its efforts to develop a nuclear ballistic missile submarine. A cherished endeavor of the Indian defense scientific community for over two decades, New Delhi has invested a great deal of financial and political capital in making the dream a reality. After the Arihant, three more submarines in the same class are currently under construction at the shipyards in Visakhapatnam. There are plans for a fifth submarine that will incorporate improvements over the lead boat. While India’s “No first use” nuclear policy mandates the establishment of “triad” of air, sea and land deterrence capabilities, policymakers and strategic experts appear convinced that the sea-based leg is the most survivable component.

Looking ahead, India’s future submarine fleet operations are likely to involve SSKs and SSNs operating in the littoral spaces, in a strategic environment sanitized and protected by SSBNs. If New Delhi can ensure compliance with present construction deadlines, it could put its submarine modernization plans back on track.

Abhijit Singh is a Senior Fellow at the Observer Research Foundation where he heads the Maritime Security Initiative.