These are my comments following March 31, 2021's "India's future 6 SSNs over 3rd Carrier: Internal Leverage."
India has been discussing the development of 6 x SSNs, now dubbed "Project 75 Alpha" since the 1990s. There has been endless talk and breathless Indian media reporting that these Indian SSNs (lets call them Alphas) will be built "very soon" for the last 15 years.
India, like most nuclear submarine-nuclear weapon powers, has had to juggle needs to fill out all 3 "legs" of the nuclear triad. That means India has simultaneously developed nuclear weapons dropped by aircraft and mounted on long range land based missiles. SSBNs with their SLBMs, are the last, hardest and longest to develop, leg of the Triad. Meanwhile India has been talking about developing Alpha concepts before it can get around to "cutting steel" - noting the highest priority of Alpha SSNs is to protect SSBNs.
INS Chakra II and eventually III
India already has been transferring technology from its 30 year old design Russian built Akula SSN known as INS Chakra II (ex Nerpa) (see artwork below). Chakra II has been under 10 year lease since 2012 from Russia - so lease expiration may be in 2022. The lease may be extended if Russia is unable to supply a later model Akula (unofficially named “Chakra III”) by about 2025. Chakra II and then III hulls were designed in the early 1980s may not be carrying torpedoes or
anti-ship missiles permitting them to be truly operational in defending Arihant-class SSBNs. I'm aware of no reports of Chakra II regularly pulling out of its base at India's Eastern Naval Command HQ - Visakhapatnam or returning to "Visak". So Chakra II's main value may be limited Indian crew training and/or Russian transfer of technology (ToT) to India.
Training and ToT would include Chakra II's 190MW OK-650 reactor which may be running in place while not actually moving the sub. An Indian variant of the full 190MW power of the OK-650 reactor will be more than adequate to power India's future 13,500 tonne (surfaced) S5-class full size SSBNs (see artwork below). Significant updated variants of the OK-650 already power Russia's latest Borei/Borey class SSBNs (see right sidebar).
Meanwhile Indian nuclear crew training continues on INS Arihant and soon Arihant's sister-sub INS Arighat.
French Barracuda SSN and K15 Reactor Value
India’s 6 x Alphas may have some features of India’s 8,140 tonne Chakra “II”. But India talks more of a 6,000 tonne Alpha that would, of course, have many design differences to a 8,140 tonne Chakra II. India understandably has an interest in French Naval Goup ToT from its 5,300 tonne (submerged) French Barracuda class very modern SSN which is likely to be much quieter than 38 year old hull technology Chakra-Akulas. Naval Group may be enticed to release more Barracuda details if this is packaged with India purchasing 6 x Scorpene (AIP) SSKs under the endlessly discussed and delayed Project-75I.
While a Russian OK-650 reactor would be too large for a 6,000 tonne Alpha Russia and India may want to investigate the Barracuda’s K15 reactor. Obtaining K15 details from France via India would constitute an intelligence coup for Russia. For India an enlarged, more powerful, variant of the K15 may be sought. The K15’s main
limitation being its need to refuel every 7-10 years. India would value a fuel core more at 15
years or even better, 35 years (whole of submarine life).
Alternatively India may rely on a highly modified variant capable of 100MW derived from the 83MW reactor used for INS Arihant (more see) .
Alpha SSN Protection of SSBNs
The Indian government
support for building 6 Alphas in India is not only a navy matter. A (or the)
major task of the Alphas will be to protect India’s growing force of SSBNs. See this generalised and very useful description of India's future nuclear subs. These
SSBNs (so far only the 2 small Arihant class) will form the most secure and potent second
strike arm of India’s nuclear triad. Two more slightly larger
Arihants are planned - making 4 Arihant small SSBNs (aka "Baby Boomers"). The Arihants however cannot accommodate
SLBMs large enough to hit the capital, Beijing, of India’s (likely) enemy China.
A more effective second
strike SSBN arm will come with the full size “S5” SSBNs (see artwork below). These S5s, which may be
launched from the late 2020s/early 2030s, will be able to accommodate 12 to 16
larger, longer range, desirably "K6" SLBMs capable of hitting Beijing.
The Arihant class and INS Chakra are current. Third one down is a possible shape and comparative size of a future Indian Alpha SSN below that is the possible shape of a future, larger Indian SSBN class (known as S5). (Artwork and captions courtesy
H I Sutton's, Forbes article of Feb 23, 2020).
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Bastion Protection of India's SSBNs
India's Arihant SSBNs are believed to be noisier than Russian or Western ideal SSBN noise levels and there are no new Alphas to protect them. So India's Arihants may need to be Bastion Protected in the Bay of Bengal by India's P8 MPAs, other jet aircraft, helicopters, surface naval ships, undersea sensors and many other sensor and weapons platforms.
It remains unknown whether India's leased Chakra II is armed, and therefore able to provide credible protection to just one Arihant. Even if a "newer" Chakra III is leased these Akulas are early 1980s hull designs, so liable to be comparatively noisy. They would need to be able to detect far quieter Pakistani AIP-Agosta-90Bs and late model Pak-AIP-Yuan SSKs as well as Chinese AIP-Yuans and Chinese SSNs.
India's first Alpha may be delivered to the Navy in the late 2020s and will need around 3 years of testing/training/working up to be fully commissioned in the 2030s. India will then probably require 2 more Alphas to form a credible protection force of 3 Alphas (noting rule of thirds). This may need to coincide with full commissioning of the first S5 full size, and quiet, SSBN.
So India may only have a fully operational force of 3 Alphas and 3 S5s in the late 2030s.
Pete
