Karanj is the third of overall six boats to be built by Indian state-owned shipbuilder, MDL in cooperation with French naval defence major, DCNS (now Naval Group).
In Indian Navy, the class is known as Kalvari-class after the lead ship of the class, INS Kalvari (S50).
INS Kalvari was commissioned into the Navy fleet during a ceremony in Mumbai on Dec. 14, 2017, after a delay of almost four years. The commissioning marked a significant milestone in India’s efforts to rebuild its depleted submarine force as China and Pakistan are building up their underwater warfare capabilities.
Before the commissioning of INS Kalvari, the Indian Navy’s fleet of diesel-electric subs consists of 13 ageing boats in various states of operational readiness while China’s People’s Liberation Army (PLA) Navy operates more than 60 submarines including 5 nuclear powered ballistic missile submarines (SSBN).
However, the INS Kalvari is still without its primary weapon system against enemy subs and surface warships, given the cancellation of a contract for Black Shark heavyweight torpedos, built by Whitehead Alenia Sistemi Subacquei (WASS), a subsidiary of Italian arms manufacturer Finmeccanica. The deal was called off due to corruption allegations.
The second ship of the class, INS Khanderi has begun its sea trials in June last year and is expected to be commissioned this year.
The Navy has recently issued a request-for-information to six foreign manufacturers for a new $8 billion contract to build six diesel-electric attack submarines with AIP technology.
INS Karanj (S52) is the third of the six Kalvari-class (Scorpene-class) diesel-electric hunter-killer submarines designed for the Indian Navy to destroy enemy submarines and warships.
The submarines of the class are designed by French shipbuilder NAVAL Group (earlier DCNS) and being manufactured at Mazagon Dock Limited (MDL) in Mumbai.
They have a displacement of 1,550 tons and a maximum submerged speed of 37 km/h. The vessel can dive to 350 meters and have a surfaced range of 12,000 km.
They are armed with heavyweight torpedoes (Varunastra), SM39 Exocet submarine-launched anti-ship missiles and naval mines.
The Exocet SM39 is a sea-skimming, subsonic, solid-fueled anti-ship missile with an approximate operational range of 50-70 kilometres depending on the variant.