INS Kalvari (S50) is the first of the Indian Navy's 6 Kalvari-class submarines built in
India under Project 75.
It is designed by DCNS (French naval defense and energy company), and under technology
transfer agreement all the submarines are being manufactured at Mazagon Dock Limited in Mumbai.
The Kalvari-class is customized version of Scorpene class, and it costs US$500 million per vessel.
Unknown to many, the name Kalvari is taken from a deep sea tiger shark, and is a revival
of the name of India's first ever submarine, the INS Kalvari S23 which was built by the
Soviet Union in Leningrad (now St. Petersburg) in 1967.
This is inline with tradition of bringing back the name of previously decommissioned vessels.
Indian Defense Minister Manohar Parrikar had launched the submarine in March last year
for sea trials, and the vessel has sailed for over 1000 hours till now.
The vessel is expected to be commissioned soon, when all the technical parameters are validated.
Let us now go into the details.
These submarines have a length of 61.7 m, and have a displacement of around 2,060 tons.
This Scorpene class submarines are constructed from special steel, and it can withstand high
yield stress because it possesses excellent tensile strength, it can withstand hydrostatic
force of high magnitude and dive deeper.
The Scorpene Submarine is designed to operate in all theatres including the Tropics.
These are purposefully designed to be compact vessels, so that these are
hard to detect by enemy.
To give viewers an idea, Scorpene class submarines have one-third the displacement of India’s
nuclear powered Ballistic Missile Submarine INS Arihant, which displaces around 6000 tons.
The Kalvari uses a diesel engine, which acts as a generator to drive an electric motor
that in turn, drives the propellers.
It has a speed of 20 knots (37 km/h) when submerged, or 12 knots (22 km/h) when on surface.
It has an endurance of 40 days to 50 days.
Thanks to the use of Air-independent propulsion system, it can stay underwater for up to 21 days at a stretch.
These can dive to depths of 350 meters.
Scorpene class is 'Attack' submarine and is meant to take out enemy submarines and ships.
These can be used to lay undersea mines as well.
It is designed to be extremely silent and is considered to be one of the stealthiest
submarines in the world.
Armament consists of 6 x 533 mm (21 in) torpedo tubes.
These tubes can be loaded with up to 18 torpedoes or anti ship missiles or 30 mines.
India may choose Black Shark torpedoes or indigenously developed Varunastra.
Both of these have speed of around 40 knots (74 km/h; 46 mph), and have range of approximately 50 km.
To know more about Varunastra check the video on above card.
For anti ship role India has selected SM 39 Exocet anti-ship missile.
Exocet missile is subsonic missile having a speed of 0.92 Mach,
and has a maximum range of 180 km.
India operates 13 conventional submarines, and an Akula-II class INS Chakra nuclear-powered
attack submarine leased from Russia.
India’s conventional submarines are aging, and consist of Russian Kilo-class and German HDW class.
Limited serviceability is a problem with these, and not all these vessels are battle ready
at any given point of time.
Given the ever growing fleet of Chinese submarines, the Indian navy is betting on the Scorpene
project to sharpen its underwater attack capabilities.
India joined the exclusive group of submarine constructing nations on February 7, 1992,
with the commissioning of the first Indian built submarine INS Shalki.
Since then, India has come a long way in submarine manufacturing.
Indian Government is targeting 30 submarines before 2022.