Why India should buy more Diesel Electric Submarines

India is on a trajectory to induct a significant number of both nuclear-propelled and nuclear-armed submarines in the coming years. However, the mainstay of its sub-surface fleet remains conventionally powered diesel-electric submarines. With eight Russian-origin Sindhughosh(Kilo) class vessels making up the most potent portion of its submarine fleet, it makes sense for India to choose a stop-gap measure that can keep the existing capability from deteriorating until Project 75I – the plan to acquire six advanced but conventionally powered submarines – can bear fruit.

While the construction and commissioning of the nuclear-propelled and nuclear-armed Arihant class ballistic missile submarines has received a great deal of attention,  it is plagued with all the problems typical of any early design. It is imperative to understand that India’s tiny ballistic missile submarines(SSBN) fleet, colloquially known as boomers, are intended to be the country’s first steps in a decades-long process to perfect. The Arihant class should be judged and treated as test beds for a strategically significant technology that will one day ensure a solid sea based leg for India’s nuclear triad.

SSBNs are generally escorted by nuclear-powered attack submarines (SSNs). Considering how the Indian Navy’s Aircraft Carrier Battle Group(CBG)-centric “Integral airpower” picket battle doctrine mirrors that of the US Navy, (except for the subsurface component that sweeps the battlespace as the CBG follows), it is a good guess that on deterrence patrols, the nuclear-powered attack submarine INS Chakra (and her future prospective replacement) has the task of escorting India’s boomer and is essentially attached to the hip with Arihant and her sister boats. This naturally leaves fewer attack submarines for other duties. With an indigenous SSN program only now entering the “detailed design phase”, it will be a good decade before we see the first vessel of the programme in service. Acquiring diesel-electrics is currently the only feasible option for closing the gap.

Not counting the sole SSN, India presently has only 14 conventional submarines: eight active vessels of the Kilo class, four of the Shishumar(Type 209) class  and two newly inducted Kalvari(Scorpene) class vessels. This relatively modest fleet is charged with protecting a huge area of responsibility and living up to India’s ambition to be a ‘net security provider’ in the Indian Ocean region and beyond.

The State of India’s Diesel Electrics

Although the induction of Exocet missiles onboard Kalvari(Scorpene) class provide a capability boost, the real teeth of the subsurface fleet remains the Klub-S tube launched cruise missiles(often described as roughly equivalent to US’s Tomahawk), that act as the force multipliers for Sindhughosh class and will play a crucial role in protecting India’s and threaten an adversary’s vital Sea Lines of Communication (SLOCs).

In light of a data breach scandal in 2016 The Government of India chose to not exercise the clause for three more vessels in the Scorpene contract with Naval Group under which The Kalvari class is being built.

Making Stop-Gap Acquisitions?

The task of bolstering India’s submarine fleet is made more difficult by the capital-crunch the Indian Navy faces in a post-COVID19 world. Consolidating and reusing existing equipment and infrastructure seems a rational course of action.

With the level of familiarity that more than three and a half decades of operating Kilo class submarines has brought the Indian Navy, can hardly be discounted when talking about stop-gap measures especially when older vessels are inevitably put through repeated life extension refits.

As things stand three or more of India’s oldest Kilo class boats will soon need to go for said life extension refits. It was earlier reported that Russia’s United Shipbuilding Corporation is offering a $1.8 Billion 3+3 deal, in which three refitted former Russian Navy hulls (that are as old as the oldest Kilo in Indian service but can be refitted to the same standards as the newest in the Indian fleet from the year 2000), can be had along with the refit work being carried out for the aforementioned. It is imperative with this background that India pursues a similar stop-gap acquisition strategy to maintain force levels.

 “These are the author’s personal views and do not necessarily reflect those of the Takshashila Institution.”