(http://www.bharat-rakshak.com/NAVY/Sindhugosh.html)

Vessel Type: Submarine, Type 877EKM.

Names & Pennant Numbers with commission dates:
INS Sindhugosh S55 (30 April 1986) - Refit Complete
INS Sindhuvaj S56 (12 June 1987) - Refit to begin in May 2005
INS Sindhuraj S57 (20 October 1987) - Refit Complete
INS Sindhuvir S58 (26 August 1988) - Refit Complete
INS Sindhuratna S59 (22 December 1988) - Refit Complete
INS Sindhukesari S60 (16 February 1989) - Refit Complete
INS Sindhukirti S61 (04 January 1990)
INS Sindhuvijay S62 (08 March 1991)
INS Sindhurakshak S63 (24 December 1997)
INS Sindhushastra S65 (19 July 2000)

Structure: The Kilo Class submarine has a single shaft with a double hull. Six compartments separated by bulkheads to enable it to remain afloat even when one is flooded. To reduce the submarine's acoustic signature, the flooding ports have been removed from the fore-body. Anechoic tiles are fitted on casings and fins. The submarine also has a new gas-freeing system to reduce risk of detection. The hull of the submarine is covered with rubber anti-sonar protection tiles which have a special ozonising layer to combat the sun's effects in tropical waters. The bow planes are positioned close to the mid-ship to improve sonar performance.

An engine change is probable during major refits in Russia which started in 1997, with INS Sindhuvir. A German-designed, Indian-built main battery, with a five year life has replaced the Russian batteries in all the vessels. Battery cooling has been improved as a result of the change.

Displacement: Surfaced; 2325 tons.
....................Dived; 3076 tons.

Dimensions: Length; 72.6 meters.
.................Beam; 9.9 meters.
.................Draught; 6.6 meters.

Diving Depth: Operational Depth; 240 meters.
...................Maximum Depth; 300 meters.

Main Machinery: Two diesel-electric motors with 3650 hp, one 5900 hp motor, two auxiliary motors with 204 hp and one economic speed motor with 130 hp.

Maximum Speed: Surfaced; 10 knots.
.......................Snorting; 9 knots.
.......................Dived; 17 knots.

Maximum Range: 6000 miles at 7 knots snorting.
.......................400 miles at 3 knots dived.

Complement: 52 (incl. 13 Officers).

Endurance at Sea: 45 days.

Radar: Navigation; MRP-25 (NATO: Snoop Tray) I-band. Has a target separation system.