Akula 2 Indian Navy

I have come to collect info related to Akula 2 Indian Navy, so would you plz let me know about the same as my one of the friend asking me about the same??

[Arvind Kumar]

Akula 2 is 3 metres (9.8 ft) longer and displaces about 700 tons (submerged displacement) more than the Akula I. The added space was used for additional quieting measures. The MGK-501 Skat sonar system on Akula-I is replaced to a new MGK-540 Skat-3 sonar system

Indian Navy operates an Akula 2 class nuclear submarine, INS Chakra, which was leased from Russia and commissioned on April 4, 2012 after India paid for its completion and sea-trials.

Class overview
Name: Akula
Builders: Sevmash
Operators: Soviet Navy
Russian Navy
Indian Navy
Preceded by: Victor class, Sierra class
Succeeded by: Yasen class
Cost: est. $1.55 billion (1995 dollars)
Built: 1983–1994
In service: 1984–present
In commission: 1984–2009
Planned: 20
Completed: 15
Cancelled: 5
Active: 5 (4 active +5 on modernization in Russia, 1 active in India)
Retired: 3
General characteristics
Type: Nuclear-powered attack submarine
Displacement: surfaced:
8,140 tons Akula I and Akula I Improved
8,450–8,470 tons Akula II and III
submerged:
12,770 tons Akula I and Akula I Improved
13,400–13,800 tons Akula II and III
Length: 110.3 m (362 ft) for Akula I and Akula I Improved
113.3 m (372 ft) for Akula II and Akula III
Beam: 13.6 m (45 ft)
Draught: 9.7 m (32 ft)
Propulsion: one 190 MW OK-650B/OK-650M pressurized water nuclear reactor
1 OK-7 steam turbine 43,000 hp (32 MW)
2 OK-2 Turbogenerators producing 2 MW
1 seven-bladed propeller
2 OK-300 retractable electric propulsors for low-speed and quiet maneuvering at 5 knots (9.3 km/h; 5.8 mph)
Speed: 10 knots (19 km/h; 12 mph) surfaced
28–35 knots (52–65 km/h; 32–40 mph) submerged[1]
Endurance: 100 days[2]
Test depth: 480 m (1,570 ft) test depth for Akula I and Akula I Improved
520 m (1,710 ft) for Akula II and III
600 m (2,000 ft) maximum operating depth
Complement: 73 for Akula I & Improved, 62 (31 officers) for Akula II & III
Sensors and
processing systems: MGK-500 or 540 active/passive suite
Flank arrays
Pelamida towed array sonar
MG-70 mine detection sonar
Electronic warfare
& decoys: Bukhta ESM/ECM
MG-74 Korund noise simulation decoys (fired from external tubes)
MT-70 Sonar intercept receiver
Nikhrom-M IFF
Armament: 4 × 533 mm torpedo tubes (28 torpedoes) and 4 × 650 mm torpedo tubes (12 torpedoes). (K-152 Nerpa has 8 × 533 mm torpedo tubes) 40 torpedoes total
1–3 × Igla-M surface-to-air missile launcher fired from sail (surface use only)
Granat cruise missiles, now Kalibr