India Launches Fourth Nuclear-Powered Ballistic Missile Submarine (S4)

At Visakhapatnam's Ship Building Centre, India launched the S4, its fourth nuclear-powered ballistic missile submarine (SSBN). Compared to its predecessor, INS Arihant (S2), this submarine is more sophisticated. An key milestone in India's naval capability has been reached with the launch.

India's SSBN Program Overview

• The initial boat is SSBN, INS Arihant which was commissioned in August 2016 and remains a technology demonstrator only under the ADV programme.
• At present, two SSBNs are in commission – INS Arihant and INS Arighaat S3.
• INS Arihant has a displacement of 6,000 tonnes with 83 MW pressurised Light Water Reactor, using enriched uranium.
• The new S4 is even more powerful than the previous version, which is largely due to the enhanced form of the nuclear reactor used.
• The S4 can transport multiple K-4 SLBMs ensuring India indigenous undersea strike range.
• India’s nuclear capability of the triad was successfully launched in November 2018 to make India capable of launching nuclear attack from land, air, and sea.
• The K-4 missile tested last year has significance to the second leg of India’s sea based nuclear deterrence.
• India has declared the nuclear strategy, under command and control system (CMD) along with no first use (NFU).
• Two more indigenous nuclear attack submarines (SSNs) to oversee and safeguard the Indo-Pacific region has been sanctioned by the government.