INS Sindhuvijay (Photo: Wikipedia/Creative Commons)
New Delhi: The Indian Navy is preparing to dispatch INS Sindhuvijay, a 34-year-old Sindhughosh-class submarine, for a comprehensive mid-life refit at Hindustan Shipyard Limited in Visakhapatnam within the coming months. This comes as the service grapples with maintaining its underwater capabilities.
The move comes as part of ongoing efforts to sustain India’s limited submarine fleet, which currently comprises seventeen diesel-powered attack submarines and one nuclear-powered ballistic missile submarine, significantly below the Navy’s operational requirements.
The Ministry of Defence has already granted acceptance of necessity for the project, with defence sources indicating that contract finalization is underway. The submarine is expected to enter HSL’s dry dock by the end of 2025 if current timelines are maintained.
INS Sindhuvijay, commissioned in April 1991, represents one of the Indian variants of the Russian Kilo-class submarines. The vessel last underwent major maintenance at Russia’s Zvezdochka Shipyard in 2005, making this refit critical for extending its operational life.
The comprehensive overhaul will include hull repairs, machinery modernization, sensor and weapons systems upgrades, and integration of contemporary technologies to ensure the submarine remains combat-effective against evolving maritime threats.
Recent success at HSL
The Visakhapatnam-based shipyard recently demonstrated its submarine refit capabilities by completing INS Sindhukirti’s refit on July 21, which included significant upgrades such as modifications for DSRV (deep-submergence rescue vehicle) integration – a first for an Indian shipyard.
HSL completed the INS Sindhukirti project four months ahead of schedule, having entered dry dock in January 2023 for what was planned as a 22-month refit. The project, valued at Rs 934 crore, involved extensive hull maintenance, propulsion system modernization, and advanced systems integration.
Fleet constraints persist
The Indian Navy’s submarine strength remains a persistent concern for maritime security planners. India’s 18 submarines are divided between two key naval bases – Mumbai and Visakhapatnam – with operations covering the Arabian Sea and Bay of Bengal.
The refit programme assumes particular significance as India faces increasing maritime security challenges in the Indo-Pacific region. Submarine capabilities remain crucial for sea denial operations, reconnaissance missions, and protecting sea lanes vital to India’s trade.
Defence analysts note that maintaining existing platforms through life-extension programmes has become essential while India awaits delivery of new submarines under various acquisition programmes. The Navy’s Maritime Capability Perspective Plan envisions a substantial expansion of the fleet, though current procurement timelines suggest continued reliance on upgraded legacy platforms.
The INS Sindhuvijay refit represents part of broader efforts to maintain submarine operational availability while indigenous shipbuilding programmes mature. HSL’s growing expertise in submarine maintenance could potentially position India as a regional hub for such specialized work, with the shipyard reportedly in discussions with Vietnam’s navy for similar projects.
Sindhughosh-class submarines
The Sindhughosh-class submarines, among which INS Sindhuvijay is one, is based on the Soviet-era Kilo design, form the backbone of India’s conventional submarine fleet. These diesel-electric vessels have a displacement of 2,325 tonnes when surfaced and 3,076 tonnes when submerged. With a length of 72–74 metres and maximum diving depth of 300 metres, they can achieve speeds of up to 19 knots underwater.
The submarines carry a crew of 53 and can operate independently for up to 45 days. Their armament includes six torpedo tubes capable of launching both conventional torpedoes and anti-ship missiles.
INS Sindhuvijay has a beam of approximately 10 metres, draught of 6.6 metres, surface speed of 10-11 knots, and submerged range of 400 nautical miles at 3 knots.
