INS Kalvari, India's first Scorpene-class submarine, to be commissioned today: Key facts

The new 1,565-tonne submarine is to be followed by five of her Scorpene sisters under the Rs 23,652 crore “Project-75”.

PTI photo

MUMBAI: The first of the indigenous Scorpene-class submarines, INS Kalvari, will be commissioned for the Indian Navy by Prime Minister Narendra Modi on Thursday.

The Prime Minister will unveil a plaque at the commissioning ceremony here.

Defence Minister Nirmala Sitharaman, Navy chief Admiral Sunil Lanba and Vice Admiral Girish Luthra, Flag Officer Commanding of the Western Naval Command, will also be present.

Here are some of the key facts to know about INS Kalvari: 

Named after the first Foxtort-class submarine, INS Kalvari was inducted into the Navy on December 8, 1967. The commissioning of its indigenous version comes days after the force observed the golden jubilee of its submarine wing.

The Scorpenes are being built by the Mazagaon Dockyard Ltd here under Project 75 with the transfer of technology from a foreign collaborator -- DCNS of France.

The state-of-the-art features of the Scorpenes include superior stealth and ability to launch crippling attacks with precision-guided weapons.

The attacks can be carried out with torpedoes both while submerged or on the surface -- in all war theatres including the tropics, giving it an unmatched invulnerability.

The new submarine has superior stealth features such as advanced acoustic silencing techniques, low radiated noise levels, hydro-dynamically optimised shape and the ability to launch a crippling attack on the enemy using precision guided weapons. 

Scorpene submarines can undertake multifarious types of missions like anti-surface warfare, anti-submarine warfare, intelligence gathering, mine laying and area surveillance.

The second of the Scorpenes under construction at MDL, INS Khanderi, was launched in January 2017, and is currently undergoing the rigorous phase of sea trials. The third Scorpene, Karanj, is being readied for launch later this year. 

The "boot together" of the submarine, wherein the five separate sections were welded into one, was completed on July 30, 2014. Kalvari is the first Indian naval vessel to be built using this modular approach of construction.

First put to sea on May 1, 2016, Kalvari has since undergone a comprehensive trial schedule to validate her capability to float, move and fight.

The submarine has an overall length of 67.5 metre and a height of about 12.3 metres. The hull form, fin and hydroplanes are specifically designed to produce minimum underwater resistance.

The boat has 360 battery cells, each weighing 750 kg, to power the extremely silent Permanently Magnetised Propulsion Motor. The stealth of the boat is further enhanced through the mounting of equipment inside the pressure hull on shock absorbing cradles.

Kalvari is named after the dreaded tiger shark, a deadly deep sea predator of the Indian Ocean.

The first Kalvari, commissioned on December 8, 1967, was also the first submarine of the Indian Navy. It was decommissioned on May 31, 1996 after nearly three decades of service.