The Indian Navy's two Project 877EKM (Nato Kilo-class) diesel-electric submarines are expected to undergo a modernisation programme in the Zvyozdochka shipyard, aimed to extend the submarines' operation life for another ten years.
RIA Novosti cited Zvyozdochka's general director, Vladimir Nikitin, as saying that the company is expected to receive at least two submarines by mid-2015 for repairs and upgrades for service life extension.
The refit programme, worth about $80m, includes overhaul of hull submarines' structures, as well as installation of improved control systems, sonar, electronic warfare systems and an integrated weapon control system.
The modernised submarines will also feature 3M-54 Club-S (SS-N-27) anti-ship cruise missiles, the Indian-developed USHUS sonar, the CCS-MK radio communications system and the Porpoise radar.
Russia has built ten Kilo-class submarines for the Indian Navy and has already overhauled five of them in INS Sindhuvir (S58), INS Sindhuratna (S59), INS Sindhughosh (S55), INS Sindhuvijay (S56) and INS Sindhurakshak (S63).
The submarines have a surfaced displacement capability of 2,300t, a maximum diving depth of 300m and can cruise at a surfaced speed of 10k with a range of 6,000nm.
Powered by diesel-electric propulsion with two diesel generators and one propulsion motor, the 877EKM-type submarine features MGK-400 sonar, active radar with a target separation system, as well as a radar warning receiver and a direction finder.
Known for being quiet boats, the Kilo-class diesel-electric submarines have also been purchased by China, Iran, Poland, Romania and Algeria.