Scorpene-class submarines, designed by France’s Naval Group, is considered to be one of the quietest conventional boats in service around the world currently

The fifth of Indian Navy’s six Scorpene-class submarines has been launched at the Mazagaon Dock by Minister of State for Defence Shripad Naik. The diesel-electric submarine, designed by France’s Naval Group, has been built by Mazagon Dock Limited in Mumbai under Project 75.

Considered to be one of the quietest conventional submarines in service around the world currently, the Indian Navy’s Scorpene-class submarines displace around 1,700 tonnes when submerged. The 67.5 metres long boats are armed with heavyweight torpedoes, anti-ship missiles and mines.

The submarines are not equipped with Air-Independent Propulsion (AIP), which gives diesel-electric/conventional submarines the ability to remain under water for relatively longer periods. Reports say the submarines will be equipped with AIP, indigenously developed by the Defence Research and Development Organisation (DRDO). The boats will be fitted with the system when undergoing their first 'mid-life refit' starting 2024-25.

Two submarines of this class — INS Kalvari (the lead ship) and INS Khanderi — are already in service with the Indian Navy. The third and fourth of the class — INS Karanj and INS Vela — are currently undergoing trials at sea.

INS Vagir will soon join these two boats for trials at sea. The two submarines are expected to be inducted into the Indian Navy over the next few months. The sixth boat of the class, INS Vagsheer, is currently under construction at the Mazagon Dock.

In 2016, the navy cancelled the option of buying three more Scorpene-class submarines under its contract with the Naval Group.

Indian Navy’s Submarine Leg

The induction of these submarines into the navy will significantly upgrade the capabilities of its under-sea leg. The navy currently has Soviet and German-origin submarines inducted in the 1980s in its under-sea leg.

The Indian Navy is also working on its next submarine project, called Project 75(I). Under this project, six submarines will be built by an Indian company along with a foreign original equipment manufacturer. The project, however, has been delayed by years and work on it is unlikely to begin anytime soon. Submarines built under this programme are likely to be inducted after 2027.

The Indian Navy is also working on nuclear-powered ballistic missile submarine (SSBNs) and nuclear-powered fast-attack submarines (SSNs). While the former are already under construction, the latter are still in the design phase.

INS Arighat, India’s second SSBN, is currently undergoing sea-trials. It is an improvement over INS Arihant, India’s first SSBN that was inducted in 2016 and completed its first deterrence patrol in 2018.