New Delhi: More than five decades after Karachi was crippled by Indian naval attacks during the 1971 war, undersea power is once again at the center of New Delhi’s strategic thinking. As German Chancellor Friedrich Merz began his visit to India on Monday amid a more volatile regional and global security environment, the discussion around Project-75I has acquired new urgency.The Indian Navy’s plan to induct six next-generation conventional submarines equipped with air-independent propulsion reflects the convergence of hard lessons of history and renewed conflict. Pakistan Following recent crises and China’s growing undersea presence in the Indian Ocean. Together, these factors are pushing India towards one of its most consequential naval procurement decisions in years, a mix of deterrence, indigenization and long-term strategic signaling.
What is Project-75I and why does it matter?
Project-75I is the Indian Navy’s flagship program to build six modern diesel-electric submarines equipped with fuel-cell-based air-independent propulsion, advanced sensors, torpedoes and missile systems. According to a PIB statement, the Defense Ministry issued a request for proposal for the project under the strategic partnership model in July 2021, calling it a key pillar of the government’s Make in India push.
The project envisages indigenous manufacturing, long-term technology transfer and creation of domestic submarine-building ecosystem. The estimated cost at the RFP stage was over Rs 40,000 crore, with current estimates putting the final contract value closer to $8 billion or about Rs 72,000 crore depending on configuration and lifecycle support.For the Indian Navy, the program addresses a critical gap. Its traditional submarine fleet is aging, while China and Pakistan’s undersea activity in the Indian Ocean and off India’s coasts is increasing.
Why was the German Type-214NG chosen?
Defense sources said that the Indian Navy has selected the German Type-214 Next Generation submarine, beating Spain’s S-80 Plus offered by Navantia. This decision was driven primarily by the maturity, acoustic stealth and low lifecycle risk of the German fuel-cell-based AIP system.
AIP allows submarines to remain underwater for weeks without surfacing or snorkeling, reducing the risk of detection. Patience and silence are decisive in disputed waters. The Type-214’s AIP technology is widely considered operationally proven, while competing systems are still undergoing verification.In undersea warfare, reliability and survivability often outweigh novelty. That calculation appears to have guided the Navy’s choice.
Make in India is at the core
Under the proposed framework, all six submarines will be constructed at MDL in India, with TKMS providing design authority, engineering expertise and technical consultancy. The indigenous content is expected to start at around 45 per cent and increase to around 60 per cent by the final boat. self-reliant india Target.TKMS and MDL signed an MoU in June last year to jointly pursue the project, laying the groundwork for the partnership. MDL’s prior experience in building the Scorpene class submarines under Project 75 earlier strengthened its case as an Indian strategic partner.
The Defense Ministry has repeatedly emphasized that Project-75I is not just about acquiring platforms but also about absorbing complex submarine design and construction technologies, as stated in the 2021 PIB release.
Pakistan, Karachi and the logic of maritime denial
India’s emphasis on undersea capability is rooted in history. During the 1971 war, Indian Naval attacks on Karachi port disrupted Pakistan’s maritime logistics and fuel supplies, hastening Islamabad’s defeat. That episode emphasized how control of the ocean can shape outcomes on land.The relevance of that lesson reemerged during Operation Sindoor in May 2025, when tensions escalated with Pakistan following a major terrorist provocation. Between 8 May and 11 May, India placed its naval forces on high alert, with Karachi again emerging as Pakistan’s most serious weakness.Karachi handles the bulk of Pakistan’s maritime trade and energy imports. India’s ability to credibly threaten that center, even without firing a shot, highlights the deterrent value of naval and undersea power. New submarines with extended underwater endurance will accelerate that leverage.
China’s undersea expansion
Beyond Pakistan, China looms large in India’s maritime threat assessment. The People’s Liberation Army Navy operates a rapidly expanding submarine fleet, including nuclear-powered platforms that are increasingly being deployed in the Indian Ocean.Chinese submarines have anchored at regional ports and patrolled close to Indian waters, while Pakistan, with Chinese assistance, is also upgrading its submarine arm. For Indian planners, this dual challenge has made restoring conventional submarine strength an urgent priority.
Project-75I is designed to bridge that gap by providing India with a survivable, persistent undersea capability suitable for monitoring choke points, tracking adversary submarines and conducting sea-denial operations.
Strategic timing of visit to Merz
Chancellor Merz’s January 12-13 visit comes amid a broader effort by Germany to expand its strategic footprint in the Indo-Pacific. As AFP reported, Berlin and New Delhi are also working toward an EU-India free trade agreement.For India, the potential submarine deal fits into a broader diversification of defense partnerships beyond old suppliers like Russia. For Germany, it represents an opportunity to establish long-term industrial and security ties with the world’s largest democracy.According to informed defense sources cited by Idrw.org, the final contract is not expected to be signed during Merz’s visit but could be concluded within the next three months, with high-level participation expected to provide political momentum.
French-origin Scorpene follow-up plan put on hold as Project-75I gets priority
In October 2025, India halted plans to build three additional French-origin Scorpene submarines at Mazagon Dock Shipbuilders Limited, while it moved decisively to pursue Project-75I, which envisages building six new-generation German-origin diesel-electric submarines at the same shipyard, The Times of India reported.Top government sources told TOI that the proposal for three additional Scorpenes, estimated to cost around Rs 36,000 crore, was “not being taken forward” at that time, although a formal decision to scrap it was not recorded. While cost negotiations for the Scorpene follow-on order were concluded last financial year, final approval from the Prime Minister-led Cabinet Committee on Security was pending.Officials told TOI that the German submarines under Project-75I were considered “a generation ahead” in terms of technology and capability. Concerns also existed about MDL’s ability to execute two complex submarine construction programs simultaneously. Six original Kalvari class submarines, including the first boat, had already been built at MDL under the first Project-75 contract signed in October 2005. INS Kalvari Commissioned in December 2017 and the sixth, INS Wagshir, was commissioned in January 2025.All six Kalvari class submarines were to be re-equipped with air-independent propulsion system developed by DRDO to improve underwater endurance. AIP allows a diesel-electric submarine to remain submerged for about two weeks, whereas boats without the system have to surface or snorkel every few days to recharge the batteries.In contrast, the submarines planned under Project-75I, to be built in partnership with Germany’s ThyssenKrupp Marine Systems, were designed from the beginning to incorporate AIPs with land-attack cruise missiles and other next-generation technologies, TOI reported.Sources told TOI that the decision to proceed with final techno-commercial negotiations for six German submarines, with an option for three more at a later stage, was taken after extensive deliberations involving the Defense Ministry, Navy and the National Security Council Secretariat. Formal contract negotiations began in September 2025.“These new generation boats under P-75I will come with design TOT (transfer of technology) and high indigenization level of around 60%. This project will serve as a bridge to the future P-76, under which conventional submarines will be built based on a completely indigenous design,” a source told TOI.Despite the pause on Scorpene expansion, officials indicated that France’s comprehensive strategic partnership with India remains strong. Talks on additional Rafale fighter aircraft for the Indian Air Force’s proposed 114 multi-role combat aircraft program advanced, with collaboration for co-development of a powerful jet engine with French major Safran for India’s fifth generation advanced medium combat aircraft almost finalized.At the time, the navy’s conventional submarine strength was six Scorpenes, six older Russian Kilo-class boats and four German HDW submarines, along with two nuclear-powered ballistic missile submarines. By comparison, China operates more than 50 diesel-electric and about 10 nuclear submarines and is in the process of supplying eight Yuan-class AIP-equipped submarines to Pakistan, which is being seen as a major capability addition for Islamabad, TOI reported.
Long term impact on India’s naval position
Once inducted, the six Type-214NG submarines will significantly enhance the Indian Navy’s capability for stealth surveillance, maritime denial and precision strike missions. Their sensors, weapons and endurance will form a key layer of India’s maritime deterrence architecture.Industrial heritage is equally important. By assimilating advanced submarine technologies, India prepares itself for future indigenous designs and follow-on projects. The role of MDL will be strengthened, and a specialized domestic supply chain will be deepened.
Project-75I is one of the most important naval procurement decisions taken by India in years. It addresses the hard lessons of 1971, recent operational realities with Pakistan and the growing challenge posed by China’s undersea expansion.As the German Chancellor arrives in India, the submarine talks underline how defense industrial cooperation has become the centerpiece of New Delhi’s foreign policy. From the burning docks of Karachi in 1971 to the tranquil depths of the Indian Ocean today, India’s maritime strategy is being reshaped through capability, indigenization and strategic foresight.
