India Launches Fourth SSBN Nuclear Submarine with 75% Indigenous Content and 3,500km Range K-4 Nuclear Ballistic Missiles

In a significant move to strengthen its nuclear deterrence capabilities, India quietly launched its fourth nuclear-powered ballistic missile submarine (SSBN) this week at the Ship Building Center in Visakhapatnam. This launch comes amidst heightened geopolitical tensions and underscores India's commitment to maintaining a credible second-strike capability.

The new submarine, codenamed S4*, boasts 75% indigenous content, a testament to India's growing prowess in naval technology. It is equipped with K-4 nuclear ballistic missiles, which have a range of 3,500 km and are capable of being fired from vertical launching systems. This enhanced range significantly expands India's nuclear strike capabilities compared to the 750 km range of the K-15 missiles carried by the first SSBN, INS Arihant.

This launch follows a series of strategic moves by the Indian Navy. Just last month, Defence Minister Rajnath Singh commissioned the second SSBN, INS Arighat, and the third, INS Aridhaman, is slated for commissioning next year. Furthermore, the Cabinet Committee on Security recently approved the construction of two more nuclear-powered attack submarines, highlighting the government's focus on enhancing underwater capabilities.

The launch of S4* occurred just a day after Defence Minister Singh inaugurated a Very Low Frequency Naval Station in Vikarabad, Telangana. This station is crucial for communication with India's strategic assets, including SSBNs, which often operate in deep-sea patrols for extended periods.

Experts believe that India's emphasis on SSBNs stems from the increasing vulnerability of aircraft carriers to long-range missiles, such as those possessed by China. SSBNs, with their virtually unlimited range and endurance, provide a reliable and survivable platform for nuclear deterrence.

The launch of S4* marks a significant step in India's pursuit of a credible nuclear triad. With INS Arihant and INS Arighat already conducting deep-sea patrols, and a Russian Akula-class nuclear-powered attack submarine expected to join the fleet on lease by 2028, India is steadily enhancing its underwater capabilities.

This is further complemented by the ongoing construction of advanced diesel-electric submarines like the Kalvari-class INS Vagsheer, and plans for three more in collaboration with the French Naval Group.

As India navigates a complex geopolitical landscape, the development and deployment of these advanced submarines are crucial for maintaining strategic autonomy and safeguarding its interests in the Indo-Pacific region.

 

[Abhishek Kumar]

if this is 4th then where is 3rd one ?

 

[Anant]

Um, incorrect specifications. Both Aridhaman (S4) and S4* (which will actually carry the pennant number S5), as well as the fifth Arihant-class boat (S6) will carry 8 K4 SLBMs or 8 K5 SLBMs (the latter under development). They may also potentially carry something like 24 K-15 SL-IRBMs apiece (three to a tube) in a manner similar to Arihant.

 

[Anant]

if this is 4th then where is 3rd one ?

Aridhaman (S4) is the third boat, and is undergoing sea trials. She is supposed to be commissioned next year, though I have a feeling it might extend to 2026.

 

[Neal.B]

Do anybody know if S4, S4*, S4** or S5 gonna carry Brahmos cruise missile?

 

[Superpower Bharat]

Do anybody know if S4, S4*, S4** or S5 gonna carry Brahmos cruise missile?

SSN will carry

 

[Dredd]

This project backed by PMO is example of success when private entity (L&T) and DRDO collaborates. We have another example of 8 year delay by MDL in scorpene case.

 

[GMR]

Excellent news.. The SSBNs' have been a success story for IN & GOI.. It demonstrate what "accountability" can achieve, unlike with DPSUs'.
Now it must be given beautiful name, rhyming with names of its sister ships..

 

[ASHOK CARROL]

Besides ship building center at Vizag , the navy and govt need to plan another submarine building base preferably on the west coast where waters are deep and hills near by .By 2050 the country needs to plan for 24-36 SSNS and 10-12 SSBns .The pace of programmes of building nuclear Subs needs to increase as budgets increase .

 

[abhinav srivastava]

Time to launch proj 76, ~10 year conventional sub development program. Do it in parallel to proj 75(I).

 

[Rational Guy]

Aridhaman (S4) is the third boat, and is undergoing sea trials. She is supposed to be commissioned next year, though I have a feeling it might extend to 2026.

Why would it extend to 2026?

 

[Akshat]

Do anybody know if S4, S4*, S4** or S5 gonna carry Brahmos cruise missile?

These are ssbn. They are supposed to carry nuclear ballistic missiles, not cruise missiles.

 

[shekhar]

Very good news, Navy is getting war machines faster than IAF, IAF's procurement decision making team should learn something here.

 

[Sudha]

Excellent news.. The SSBNs' have been a success story for IN & GOI.. It demonstrate what "accountability" can achieve, unlike with DPSUs'.
Now it must be given beautiful name, rhyming with names of its sister ships..

Private sector need not even be accountable for the profit motive as well as patroitism drives them unlike DPSUs. There are internal accountability to meet the timeline. While DPSU personnels know very well their jobs are secure even if they spend more time in canteen. Well done & Kudos for L&T engineers.

 

[abhinav srivastava]

I was not expecting 4th nuclear sub so soon. Hope similarly they surprise with Kaveri engine 🙂.

 

[Gaurav Sharma]

Do anybody know if S4, S4*, S4** or S5 gonna carry Brahmos cruise missile?

Only SSN can carry cruise missiles; they are slightly shorter in size but are relatively faster in speed than SSBN. Also, SSN can be used for tactical offensive operations like attack on aircraft carrier or larger ships/submarines.

 

[Sandeep]

This is very good news but they shouldn’t manufacture anymore than the 4 submarines as India needs to develop and make the much larger 12000t S5 class submarine which is a priority to use against China. So we need at least 6-10 SSBN if we want to protect the country and Indian Ocean.

 

[NSR]

Great for a ROBUST Indian Nuclear Triad for India.

But the next and last two SSBNs should have the launch capabilities to launch 7000+ kms SLBMs bring all of china into their range from the deep waters of Bay of Bengal.

Way to go!!!

 

[Varaaah]

Good. But one must work to create a nuclear reactor which should be refuelled after at least 15 years and not after just 5 years, like this one.

 

[Tailless Baboon]

That's how it should be- silent, No bravado

 

[Anant]

Why would it extend to 2026?

I am looking at it from the perspective of when it was launched, and taking into account the longer testing period due to the revised design. S4's increased length means the hydrodynamic performance will have changed. That will require more testing and the like.

Regardless, even if it is 2026, my rough calculations put it around the second quarter of that year. It could well enter service earlier than that.

 

[desigandu]

I am looking at it from the perspective of when it was launched, and taking into account the longer testing period due to the revised design. S4's increased length means the hydrodynamic performance will have changed. That will require more testing and the like.

Regardless, even if it is 2026, my rough calculations put it around the second quarter of that year. It could well enter service earlier than that.

Just saw on X that our project alpha SSNs may be more like the Russian SSGNs, with long range cruise/hypersonic missile capability - thoughts?