INS Kalvari (S21)
| INS Kalvari (S21) at sea | |
| History | |
|---|---|
| India | |
| Name | Kalvari | 
| Namesake | Kalvari (S23) | 
| Ordered | 2005 | 
| Builder | Mazagon Dock Limited, Mumbai | 
| Launched | 27 October 2015 | 
| Acquired | 2 December 2017 | 
| Commissioned | 14 December 2017 | 
| Identification | S21 | 
| Motto | Ever Onward | 
| Status | in active service | 
| Badge | |
| General characteristics | |
| Class & type | Kalvari-class submarine | 
| Displacement | 
 | 
| Length | 67.5 m (221 ft) | 
| Beam | 6.2 m (20 ft) | 
| Height | 12.3 m (40 ft) | 
| Draught | 5.8 m (19 ft) | 
| Propulsion | 
 | 
| Speed | 
 | 
| Range | 
 | 
| Endurance | 50 days | 
| Test depth | 350 metres (1,150 ft) | 
| Complement | 
 | 
| Electronic warfare & decoys | C303/S anti-torpedo countermeasure system | 
| Armament | 
 | 
INS Kalvari (S21) (lit. 'Tiger shark') is the first of the six indigenous Kalvari-class submarines currently in service with the Indian Navy. It is a diesel-electric attack submarine which is designed by DCNS (French naval defence and energy company) and was manufactured at Mazagon Dock Limited in Mumbai.