Why Project-75I Submarine Upgrade India Is Suddenly in Focus?
Silent, unseen, and decisive. That is how modern submarine warfare works—and right now, Project-75I submarine upgrade India is back at the centre of India’s strategic thinking.
More than five decades after Indian naval strikes crippled Karachi during the 1971 war, undersea power is once again shaping New Delhi’s defence priorities. With rising friction with Pakistan, a growing Chinese naval presence in the Indian Ocean, and an ageing submarine fleet, the Indian Navy’s push for Project-75I has gained fresh urgency.
This is not just a military acquisition. It is a long-term strategic decision that blends deterrence, industrial capability, and geopolitical signalling. So what exactly is Project-75I, and why does it matter so much now?
What Is Project-75I Submarine Upgrade India and Why It Matters?
Project-75I submarine upgrade India is the Indian Navy’s flagship programme to induct six next-generation conventional submarines equipped with advanced air-independent propulsion, modern sensors, torpedoes, and missile systems.
The Ministry of Defence issued the Request for Proposal in July 2021 under the Strategic Partnership Model, positioning the project as a key pillar of the government’s Make in India initiative. The estimated cost has steadily climbed, with current assessments placing the final value near $8 billion, or roughly ₹72,000 crore.
For the Indian Navy, this programme addresses a serious operational gap. India’s conventional submarine fleet is ageing at a time when both Pakistan and China are increasing undersea activity in the Indian Ocean region. Project-75I submarine upgrade India is designed to restore balance and credibility below the surface.
Why the German Type-214NG Was Chosen?
One of the most asked questions around Project-75I submarine upgrade India is why the Indian Navy selected the German Type-214 Next Generation submarine over competing options.
The answer comes down to maturity, reliability, and survivability. The German fuel-cell-based air-independent propulsion system is already operational and widely regarded as proven. In contrast, rival systems are still undergoing validation.
Air-independent propulsion allows submarines to remain submerged for weeks without surfacing, drastically reducing detection risk. In modern naval warfare, endurance and silence often outweigh cutting-edge but untested technology. This practical logic guided the Navy’s decision.
Make in India at the Heart of Project-75I Submarine Upgrade India
Project-75I submarine upgrade India is not an off-the-shelf foreign purchase. All six submarines will be built in India at Mazagon Dock Shipbuilders Limited in Mumbai, with Germany’s ThyssenKrupp Marine Systems providing design authority and technical support.
Indigenous content is expected to begin at around 45 percent and rise to nearly 60 percent by the final submarine. This aligns with Atmanirbhar Bharat goals and aims to create a long-term domestic submarine-building ecosystem.
MDL’s prior experience building six Kalvari-class Scorpene submarines under the earlier Project-75 significantly strengthened its credentials. According to the defence ministry, Project-75I is about absorbing complex design knowledge, not just acquiring platforms.
Pakistan, Karachi, and the Logic of Sea Denial
India’s renewed focus on undersea warfare is deeply rooted in history. During the 1971 war, Indian naval strikes on Karachi port severely disrupted Pakistan’s logistics and fuel supply, accelerating its defeat.
That lesson resurfaced during recent periods of heightened tension with Pakistan. Karachi remains Pakistan’s most critical maritime hub, handling the majority of its trade and energy imports. Even the credible threat of disruption serves as a powerful deterrent.
With Project-75I submarine upgrade India, enhanced underwater endurance and stealth significantly strengthen India’s sea-denial capability. The ability to threaten vital maritime infrastructure without being seen changes the strategic equation—without a single shot being fired.
China’s Expanding Undersea Footprint
Beyond Pakistan, China represents a far larger long-term challenge. The People’s Liberation Army Navy operates a rapidly growing submarine fleet, including nuclear-powered boats that regularly deploy into the Indian Ocean.
Chinese submarines have docked at regional ports and conducted patrols close to Indian waters. At the same time, China is supplying Pakistan with Yuan-class air-independent propulsion submarines, giving Islamabad a substantial capability boost.
For Indian planners, this twin challenge has made Project-75I submarine upgrade India an urgent priority. The new submarines will enable persistent surveillance, choke-point monitoring, and effective tracking of adversary undersea movements.
Why the Scorpene Follow-On Plan Was Put on Hold?
In late 2025, India paused plans to build three additional French-origin Scorpene submarines, even as it moved decisively toward Project-75I. The Scorpene extension, estimated at around ₹36,000 crore, did not receive final political clearance.
Officials assessed that the submarines planned under Project-75I submarine upgrade India were a generation ahead in terms of technology and capability. There were also concerns about MDL’s ability to simultaneously execute two complex submarine construction programmes.
Unlike the Scorpenes—where air-independent propulsion is being retrofitted later—the Project-75I submarines are designed with AIP integrated from the outset, along with land-attack cruise missiles and next-generation systems.
Long-Term Impact of Project-75I Submarine Upgrade India
Once inducted, the six Type-214NG submarines will significantly enhance the Indian Navy’s ability to conduct covert surveillance, sea denial, and precision strike missions.
Equally important is the industrial legacy. By absorbing advanced submarine design and construction technologies, India positions itself for future indigenous programmes, including the planned Project-76.
Project-75I submarine upgrade India is one of the most consequential naval procurement decisions India has taken in years. It reflects lessons from history, responds to present-day threats, and lays the groundwork for a more secure maritime future.
From Karachi’s burning docks in 1971 to the silent depths of the Indian Ocean today, India’s naval strategy is evolving—quietly, deliberately, and with long-term vision.
