Sonar, torpedoes, guarding coasts: Navy commissions indigenous INS Mangrol

INS Mangrol is an Indian Navy warship designed specifically for anti-submarine operations in shallow coastal waters. It matters because submarines operating near ports, harbours and coastal approaches can threaten important maritime infrastructure. Larger warships may be less suited to these confined areas.

The vessel carries the Abhay hull-mounted sonar, lightweight torpedoes, an indigenous anti-submarine rocket launcher and the Mareech Advanced Torpedo Decoy System. These systems help it detect and track underwater contacts, attack hostile submarines and counter incoming torpedoes. Three diesel engines and waterjet propulsion give it high manoeuvrability.

Built by Cochin Shipyard Limited, INS Mangrol has more than 80 per cent indigenous content. It can also conduct underwater surveillance, low-intensity maritime operations and mine warfare. Commissioned in Mumbai in 2026, it strengthens coastal defence and supports the Navy’s effort to replace older Abhay-class corvettes.

The Navy’s current fleet comprises 151 platforms. Vice Admiral Sanjay Vatsayan said this includes 131 ships and 20 submarines. These figures show the scale of India’s maritime force and the importance of steadily adding newer platforms.

Expansion is already under way. Forty-two ships are under construction at Indian shipyards. Acceptance of Necessity has also been granted for 69 ships, six submarines and 120 Fast Interceptor Craft. The Navy commissioned 10 ships in 2026 and expected another eight to enter service by year-end.

The fleet is projected to grow beyond 170 platforms over the next few years. The Navy expects a new ship to be commissioned every 40 to 50 days. By 2034, about 60 per cent of its platforms are expected to be less than 10 years old on average, improving fleet renewal.

INS Mangrol is designed for shallow and confined waters because coastal areas create special operating challenges. Ports, harbours and approaches may not provide the space or depth needed by larger warships. A craft built for these conditions can patrol nearer to shore and protect important maritime infrastructure.

Its three diesel engines and waterjet propulsion provide high manoeuvrability. That makes the vessel suitable for navigating restricted areas while searching for underwater threats. Its sonar and anti-submarine weapons allow it to detect, track and counter submarines operating in those waters.

The design fills a specific coastal security role rather than replacing every type of naval ship. INS Mangrol can also work with maritime patrol aircraft, helicopters and other vessels. Alongside anti-submarine warfare, it supports underwater surveillance, low-intensity maritime operations and mine warfare in coastal areas.

INS Mangrol’s anti-submarine systems perform different jobs in sequence. The Abhay hull-mounted sonar helps detect underwater contacts and track them. This gives the crew information needed to assess and respond to a possible hostile submarine.

Lightweight torpedoes provide a weapon for attacking submarines. The indigenous anti-submarine rocket launcher adds another way to engage underwater threats. Together, these systems allow the craft to counter submarines in the shallow and confined waters for which it was designed.

The Mareech Advanced Torpedo Decoy System provides defence against incoming torpedoes. It deploys countermeasures intended to draw or divert such weapons away from the ship. The vessel can therefore search, attack and protect itself during one operation. Its systems also support cooperation with aircraft, helicopters and other naval vessels during surveillance missions.

Hostile submarines operating undetected near India’s coast could create a serious security problem. They might approach ports, harbours or other strategically important maritime infrastructure without timely warning. This would make it harder for the Navy to protect coastal approaches and respond to underwater threats.

The article links coastal anti-submarine warfare directly to detection, tracking and counteraction. INS Mangrol uses hull-mounted sonar to search underwater, then carries lightweight torpedoes and an anti-submarine rocket launcher to engage hostile submarines. It can also deploy Mareech decoys against incoming torpedoes.

The Navy is strengthening this capability through Mahe-class vessels and coordination with maritime patrol aircraft, helicopters and other ships. These measures improve surveillance around the coast. They also support protection of ports and infrastructure while replacing ageing Abhay-class corvettes with newer, highly manoeuvrable shallow-water craft.

The Navy is replacing the Abhay-class corvettes because they are ageing. Those vessels entered service between 1989 and 1991. Their replacement is part of a broader effort to renew the fleet and strengthen anti-submarine warfare close to India’s coast.

The Mahe-class is designed specifically for shallow and confined waters. INS Mangrol carries the Abhay hull-mounted sonar, lightweight torpedoes, an indigenous anti-submarine rocket launcher and the Mareech torpedo decoy system. Three diesel engines and waterjet propulsion improve manoeuvrability in restricted areas.

This gives the Navy a newer platform for detecting, tracking and countering submarines around ports, harbours and coastal approaches. The craft also supports surveillance, mine warfare and low-intensity maritime operations. INS Mangrol’s more than 80 per cent indigenous content supports domestic shipbuilding while expanding the Navy’s coastal capability.

A navy uses sonar by sending or listening for underwater sound. Active sonar sends a sound signal and studies its return from an object. Passive sonar listens for sounds produced by vessels. These methods can help a ship detect, locate and track a submarine. The article identifies INS Mangrol’s Abhay hull-mounted sonar as its main detection system.

Detection becomes harder in shallow coastal water because the environment is confined and underwater sound can interact with the seabed and surface. Reflections and other sounds can complicate the contact picture. This is established sonar knowledge beyond the article’s detailed explanation. The article describes shallow waters as presenting specific challenges.

INS Mangrol addresses this role through a specialised design and high manoeuvrability. Its sonar works alongside lightweight torpedoes, an anti-submarine rocket launcher and Mareech decoys. It can also coordinate with aircraft, helicopters and other naval vessels to strengthen surveillance and anti-submarine operations.