INS Kalvari (S23): general characteristics and historic legacy unveiled

The lead ship of the Indian Navy’s Kalvari-class submarines, INS Kalvari (S23), was put into service on December 8, 1967. Given its name, which comes from the Malayalam word for “tiger shark,” it demonstrated strength during its operational tenure till 1992.

The lead ship of the Indian Navy’s Kalvari class, a prominent class of diesel-electric submarines, is INS Kalvari (S23). Construction of the Soviet Navy’s Foxtrot-class submarine B-51 began on December 27, 1966, at Novo-Admiralty on Galerniy Island in Leningrad.

After being launched on April 15, 1967, the submarine was built until September 26, 1967, and on December 8, 1967, at Riga, Soviet Union, it was formally put into service by the Indian Navy. Every year on December 8, we observe Submarine Day to honour the historic commissioning of INS Kalvari.

The term ‘Kalvari’ has cultural importance because it comes from the Malayalam language and means ‘tiger shark.’ The tiger shark, a dangerous deep-sea predator located in the Indian Ocean, is comparable to the submarine in terms of strength, agility, and predatory force, which is why this name was chosen.

INS Kalvari distinguished itself in service to the Indian Navy during its active life till it was decommissioned in 1992. INS Kalvari holds significant historical value in the maritime domain due to its distinction as the first submarine ever to be commissioned by the Indian Navy.

General Characteristics:

The Kalvari-class submarine INS Kalvari (S23) has a displacement of 1,950 tonnes when it is surfaced and 2,475 tonnes when it is submerged. The submarine is built for efficiency and versatility, measuring 91.3 metres in length, 7.5 metres in beam, and 6 metres in draught.

When underwater, it can attain 15 knots, which is equivalent to 28 km/h (17 mph), and 16 knots when it is surfaced, indicating a speed capability of 30 km/h (18 mph). With a surface operating range of 20,000 miles at 8 knots and a submerged operating range of 380 miles at 10 knots, it has an impressive operational range.

Testing depth for the submarine is up to 250 metres, demonstrating its sturdy build and aptitude for navigating difficult underwater settings. Eight officers are among the seventy-five people on board the INS Kalvari (S23), indicating the level of coordination needed to keep the aircraft in operation.

It has ten torpedo tubes of 533 mm (21 inches) in length, which can hold twenty-two SET-65E/SAET-60 torpedoes. It can also be equipped with 44 mines instead of torpedoes, giving it more tactical versatility. This extensive feature set emphasises the INS Kalvari’s standing as a powerful and versatile Kalvari-class submarine.