India is close to finalising one of its largest naval acquisitions in decades. The long-delayed Project-75I submarine deal with Germany, estimated to cost around Rs 90,000 crore, is expected to be signed in the coming weeks, according to German Ambassador to India Philipp Ackermann. However, in July 2021, the Ministry of Defence had said that the project was initially estimated to be over Rs 40,000 crore.
The programme will see six next-generation conventional submarines built at Mazagon Dock Shipbuilders Ltd in partnership with ThyssenKrupp Marine Systems. Beyond the numbers, the deal carries significance for the Indian Navy’s underwater combat readiness in the Indian Ocean Region and for the government’s push to build advanced defence platforms at home.
Recently, Ackermann expressed confidence that the agreement could be signed in the coming weeks. This signals that years of negotiations may finally be nearing completion.
Why Project-75I is strategically important
The Indian Navy has repeatedly highlighted the need to modernise its conventional submarine fleet as maritime competition intensifies across the Indian Ocean Region (IOR).
Conventional diesel-electric submarines remain crucial for missions such as sea-denial operations, intelligence gathering, surveillance, anti-submarine warfare and protecting critical sea lanes.
Project-75I is expected to address capability gaps by introducing submarines with Air Independent Propulsion (AIP) technology, allowing them to remain submerged for significantly longer periods than conventional diesel-electric submarines.
The project also supports India’s broader objective of reducing dependence on imported military platforms by manufacturing advanced defence equipment within the country.
Indigenous manufacturing at the core
Unlike previous submarine acquisitions, Project-75I places considerable emphasis on domestic production and technology transfer.
Under the proposed arrangement, Germany’s TKMS will partner with Mazagon Dock Shipbuilders to construct the submarines in India, enabling Indian industry to acquire advanced submarine-building expertise while strengthening the domestic defence manufacturing ecosystem.
The programme is expected to create high-skilled employment, deepen India’s naval industrial base and support future indigenous submarine development.
Type 214 expected to form the foundation
According to the data available on TKMS Group website, the project is expected to be based on TKMS’ Type 214 submarine, one of the world’s most advanced conventional diesel-electric attack submarines. Developed by Germany’s Howaldtswerke-Deutsche Werft (HDW), the Type 214 combines the proven hull design of the Type 209 family with modern hydrogen fuel-cell-based Air Independent Propulsion technology derived from the Type 212A.
Its biggest operational advantage lies in its ability to remain underwater for extended periods without surfacing or using a snorkel, significantly reducing the chances of detection.
What makes the Type 214 different?
The submarine measures 65 metres in length, has a beam of 6.3 metres, and displaces between 1,690 tonnes on the surface and 1,860 tonnes when submerged. Its pressure hull is built using HY-100 high-yield steel, designed to minimise magnetic signatures while improving structural strength.
Longer endurance, greater stealth
According to the official website, one of the defining features of the Type 214 is its underwater endurance. Using its AIP system, the submarine can reportedly remain submerged for up to three weeks, eliminating the need to frequently surface for oxygen, a key vulnerability for conventional submarines.
It is reported that it has an operational endurance of approximately 84 days, a surfaced range of around 12,000 nautical miles, and an underwater range exceeding 1,200 nautical miles using fuel-cell propulsion.
The submarine can achieve speeds of up to 20 knots underwater while operating at depths exceeding 250 metres, with estimates placing its maximum diving depth at around 400 metres.
Designed for modern naval warfare
The Type 214 is equipped with eight 533 mm torpedo tubes capable of launching heavyweight torpedoes such as the DM2A4 and Black Shark, along with submarine-launched anti-ship missiles, including the Sub-Harpoon.
Its combat suite includes the ORCCA Combat Management System, the ISUS 90 sonar and weapon control system, and the SPHINX-D Low Probability of Intercept navigation radar.
The submarine also incorporates torpedo countermeasure systems, supports special operations forces, and allows flexible weapon configurations depending on mission requirements.
Built to remain undetected
Stealth remains one of the Type 214’s biggest strengths. The submarine features an X-rudder configuration that improves underwater manoeuvrability, while its permanent magnet synchronous electric motor reduces noise levels during operations.
Its acoustic and magnetic signatures have been minimised to make detection by enemy sensors more difficult, while high shock-resistance standards enhance survivability during combat.
It is reported that the vessel is designed to operate with a crew of as many as 27 personnel, including five officers and 22 sailors.