NEW DELHI: State-run Cochin Shipyard Limited (CSL) on Friday delivered Mangrol, the third of eight anti-submarine warfare shallow water craft (ASW-SWC) being built for the Indian Navy at Kochi, bringing the number of coastal submarine hunters handed over under a 16-vessel programme to seven, marking a most productive phase.
The vessel will now undergo pre-commissioning procedures before joining the fleet.
Six such shallow water sub-hunters have already been commissioned. Mangrol will be the seventh and is part of a wider surge in inductions this year.
As reported earlier, the Navy expects to commission 18 warships in 2026, its largest single-year force accretion, against 14 vessels commissioned last year.
Mangrol, named after the coastal town in Gujarat, was launched in 2023 along with sister ships Mahe and Malvan. Mahe, the lead ship, was delivered and commissioned last year, while Malvan was delivered in March and commissioned at Karwar in July.
Five more vessels are under construction at Kochi, with deliveries expected through 2028.
The inductions come amid growing Chinese underwater activity in the Indian Ocean Region, where People's Liberation Army Navy submarines and survey vessels have been deploying with increasing regularity and as Pakistan begins fielding eight Chinese-origin Hangor-class boats fitted with air-independent propulsion, which allows a conventional submarine to stay submerged far longer than a standard diesel-electric design.
The lead boat, PNS Hangor, was commissioned at Sanya in China and reached Karachi in June.
"With a limited surface fleet and few dedicated anti-submarine platforms of its own, Pakistan is expected to lean heavily on its submarine arm in any future conflict," sources said. That places a premium on India's ability to police the approaches to its ports, anchorages and coastal shipping lanes.
The ASW-SWCs are intended to hold precisely that space. By taking on the hunt in the littorals, they free frontline destroyers and frigates for blue-water tasking, while screening harbours and offshore assets in waters where larger warships cannot easily operate.
The 78-metre craft are designed to detect and engage diesel-electric submarines operating in shallow, acoustically cluttered coastal waters, where larger warships face greater operational constraints.
They can also undertake mine-laying, subsurface surveillance, low-intensity maritime operations and search-and-rescue missions. The craft can operate up to about 200 nautical miles from the coast. They displace between 900 and 1,100 tonnes, can make 25 knots and have an endurance of about two weeks.
Powered by a diesel engine and waterjets, the vessels have a shallow draught of about 2.7 metres, allowing them to manoeuvre in confined waters while reducing underwater radiated noise. They are the largest group of waterjet-propelled warships in the Navy.
For submarine hunting, the craft carry the DRDO-developed Abhay hull-mounted sonar and a towed low-frequency variable-depth sonar.
Their weapons fit includes an RBU-6000 anti-submarine rocket launcher, triple torpedo tubes firing the Advanced Lightweight Torpedo, a 30 mm naval gun and mine-laying rails.
The class has more than 80 per cent indigenous content, with systems and components supplied by Bharat Electronics, L&T Defence, Mahindra Defence Systems, the Naval Physical and Oceanographic Laboratory and over 20 Indian MSMEs.
The Defence Acquisition Council (DAC) cleared 16 ASW-SWCs in December 2013 at an estimated Rs 13,440 crore. Contracts worth about Rs 6,311 crore each were signed with CSL and state-run Garden Reach Shipbuilders and Engineers (GRSE) in April 2019.
The vessels replace the four Soviet-origin Abhay-class corvettes, commissioned between 1989 and 1991. The last, INS Abhay, was decommissioned on October 6 last year, weeks before the first of the new craft from Kochi entered service.
The CSL programme has faced delays, with engine and sonar supply issues pushing the first delivery back from the original November 2024 target by nearly a year.
GRSE's parallel Arnala-class line is four ships ahead, having delivered Arnala, Androth, Anjadip and Agray, all of which have since been commissioned. All eight of its hulls have been launched, and the shipyard has said it expects to complete the project in the current financial year.
The Navy continues to face gaps in its wider anti-submarine warfare capability, particularly in dedicated ASW helicopters, even as it expands towards a planned fleet of roughly 175-200 warships.