INS Sindhudhvaj (S56)

History
Name	INS Sindhudhvaj
Commissioned	12 June 1987
Decommissioned	16 July 2022
General characteristics
Class and type	Sindhughosh-class submarine
Displacement	2325 tons surfaced; 3076 tons submerged;
Length	72.6 m (238 ft)
Beam	9.9 m (32 ft)
Draught	6.6 m (22 ft)
Propulsion	2 × 3,650 hp (2,720 kW) diesel-electric motors; 1 × 5,900 hp (4,400 kW) motor; 2 × 204 hp (152 kW) auxiliary motors; 1 × 130 hp (97 kW) economic speed motor;
Speed	Surfaced;11 knots (20 km/h); Snorkel Mode; 9 knots (17 km/h); Submerged;19 knots (35 km/h);
Range	Snorting: 6,000 mi (9,700 km) at 7 kn (13 km/h); Submerged: 400 miles (640 km) at 3 knots (5.6 km/h);
Endurance	Up to 45 days with a crew of 52
Test depth	Operational depth; 240 m (790 ft); Maximum depth; 300 m (980 ft);
Complement	52 (incl. 13 Officers)
Armament	9M36 Strela-3 (SA-N-8) SAM launcher; Klub-S (3M-54E) ASCM; Type 53-65 passive wake homing torpedo; TEST 71/76 anti-submarine, active-passive homing torpedo; 24 DM-1 mines in lieu of torpedo tube;

INS Sindhudhvaj (S56) was a Sindhughosh-class submarine of the Indian Navy^[2] in service from 1987 until 16 July 2022, when she was decommissioned.^[3]

The name Sindhudhvaj means "flag bearer at sea". The submarine's crest depicts a grey nurse shark. Sindhudhvaj was the submarine to operationalise several indigenously built systems including the USHUS sonar, the Rukmani and MSS satellite communication systems, the inertial navigation system and the torpedo fire control system.^[4]

The submarine also completed a successful mating and personnel transfer with a deep-submergence rescue vehicle. It was the only submarine to be awarded the Chief of the Naval Staff's Rolling Trophy for Innovation by Prime Minister Narendra Modi.^[4]