Nuclear-powered Submarine

Nuclear-powered Submarine

Subject – Security

Context – The United States, United Kingdom, and Australia announced a new defence deal, under which America and Britain will help Australia deploy nuclear-powered submarines in the Pacific region.

Concept –

• The nuclear-powered submarines will give Australia naval heft in the Pacific, where China has been particularly aggressive. While the US and Britain have had the capability for decades, Australia has never had an n-sub.
• China has nuclear-powered submarines, as well as submarines that can launch nuclear missiles.
• A nuclear-powered submarine gives a navy the capability to reach far out into the ocean and launch attacks.
• Unlike conventional submarines, which are generally considered helpful for defensive purposes, the ability of a nuclear-powered submarine to go long distances, at a higher speed, without being detected gives a nation the ability to protect its interests far from its shores.
• In the context of the AUKUS agreement, nuclear-powered submarines will give the Royal Australian Navy the capability to go into the South China Sea, where China is increasingly getting aggressive, to protect its assets and conduct patrols — even though this has not been spelt out by the three countries.
• The US has in the past shared its nuclear propulsion technology only with the UK, in accordance with the nuclear power sharing arrangement that the two countries have had since 1958.
• A nuclear-powered submarine is classified as an “SSN” under the US Navy hull classification system, wherein ‘SS’ is the symbol for submarine, and ‘N’ stands for nuclear. A nuclear-powered submarine that can launch ballistic missiles is called “SSBN”.
• Conventional diesel-engine submarines have batteries that keep and propel — though not very fast — the vessel underwater. The life of these batteries can vary from a few hours to a few days.
• The newer Air-Independent Propulsion (AIP) submarines have additional fuel cells that allow them to stay underwater for longer and move faster than the conventional vessels. However, the fuel cells are used only at strategic times, when the endurance to remain submerged is required.
• Both conventional and AIP subs need to come to the surface to recharge their batteries using the diesel engine. The diesel engine also propels the vessel on the surface. However, the fuel cells of AIP can only be charged at on-land stations, not while at sea.
• The great advantage of an SSN is that its nuclear-powered propulsion gives the submarine a near infinite capacity to stay dived. Since it is propelled by a nuclear-powered engine rather than by batteries, it does not have to emerge on the surface at all, except to replenish supplies for the crew.
• SSNs are also able to move faster underwater than the conventional submarines. Added together, these advantages allow a navy to deploy these submarines quicker and at farther distances.

Do you know?

At present only 6 countries have nuclear powered submarine

Does India have nuclear-powered submarines?

• Yes, India is among the six nations that have SSNs. The other five are the US, the UK, Russia, France and China.
• India has had the capacity since it got the Soviet-built K-43 Charlie-class SSN in 1987. Commissioned with the Red Fleet of the USSR in 1967, it was leased to the Indian Navy, and was rechristened INS Chakra. The submarine was decommissioned in 1991.
• In 2012 India got another Russian SSN on a 10-year lease, called INS Chakra 2.
• In the mean time, India was working on building its own SSN, and the first Indian nuclear submarine, the INS Arihant, was commissioned in 2016. A second Arihant-class submarine, INS Arighat, was secretly launched in 2017, and is likely to be commissioned soon.
• After it demonstrated the capability to launch nuclear weapons in 2018, the INS Arihant is now classified as a Strategic Strike Nuclear Submarine or SSBN, which means it is a nuclear-powered ballistic submarine.
• INS Arihant is important because it completes India’s nuclear triad, which means that the country has the capacity to launch nuclear missiles from land, aircraft, and submarine.

To know more about AUKUS, please click here.