Why Is India's Project 75 So Important for Modern Naval Warfare?
Modern naval warfare is no longer defined only by powerful surface warships or advanced fighter aircraft. Today, underwater dominance has become equally important. Stealth submarines can monitor enemy movements, protect maritime borders, gather intelligence, deter hostile naval forces, and launch precision attacks while remaining largely hidden beneath the sea.
As geopolitical competition expands across the Indo-Pacific region, countries are investing heavily in advanced submarine technologies that improve survivability, endurance, and operational flexibility.
India's response to this changing security environment is Project 75, a long-term submarine acquisition and modernization program designed to strengthen the Indian Navy's underwater capabilities with advanced conventional submarines.
Rather than representing a single submarine, Project 75 is a comprehensive naval program aimed at introducing modern stealth submarines equipped with advanced sensors, sophisticated combat management systems, powerful torpedoes, anti-ship missiles, and improved acoustic performance.
An equally important objective of the program has been the development of India's domestic shipbuilding capability through technology transfer, industrial collaboration, and local manufacturing expertise.
This approach not only enhances national security but also supports the long-term growth of India's defense manufacturing ecosystem.
As underwater surveillance technologies continue improving worldwide, submarines must become quieter, smarter, and more difficult to detect.
Project 75 addresses these evolving requirements by introducing platforms specifically designed for modern underwater operations rather than relying on aging submarine fleets.
Why Does India Need Advanced Conventional Submarines?
India's geographical position makes maritime security one of its highest strategic priorities.
The country has a coastline stretching over thousands of kilometers and depends heavily on sea routes for international trade, energy imports, and commercial shipping.
The Indian Ocean carries a substantial share of global maritime commerce, making it one of the world's most strategically significant regions.
Protecting these sea lanes requires continuous maritime surveillance and a credible underwater defense capability.
Unlike surface warships, submarines can operate covertly for extended periods, making them valuable assets for intelligence gathering, surveillance, sea denial operations, and strategic deterrence.
They also provide naval commanders with greater operational flexibility during both peacetime and periods of heightened tension.
Conventional diesel-electric submarines remain particularly effective in regional waters because of their relatively quiet operation and suitability for coastal and littoral missions.
Modern upgrades, including improved sonar systems, advanced combat electronics, enhanced weapon integration, and technologies such as Air-Independent Propulsion (AIP), have significantly increased their operational effectiveness.
For India, maintaining a modern conventional submarine fleet complements other naval assets while strengthening overall maritime security across the Indian Ocean region.
What Is Project 75?
Project 75 is a major Indian Navy submarine acquisition program under which a new generation of Kalvari-class conventional diesel-electric attack submarines has been built in India using technology transferred through an international industrial partnership.
The program represents far more than the procurement of new submarines.
It has helped establish advanced shipbuilding infrastructure, improve domestic manufacturing capabilities, develop specialized engineering expertise, and strengthen India's long-term ability to construct complex naval platforms.
Each submarine is designed with a strong emphasis on stealth, survivability, underwater endurance, and advanced combat capability.
Compared with earlier generations, these submarines feature improved acoustic performance, modern sonar suites, integrated combat management systems, precision-guided weapons, and enhanced operational flexibility.
Their primary missions include anti-submarine warfare, anti-surface warfare, intelligence collection, maritime surveillance, special operations support, and strategic deterrence.
As underwater warfare continues evolving through advances in sensors, autonomous systems, artificial intelligence, and network-centric operations, Project 75 provides India with a more capable platform for meeting future maritime security challenges.
The Kalvari-Class: The Core of Project 75
At the heart of Project 75 is the Kalvari-class, a fleet of modern diesel-electric attack submarines designed to strengthen the Indian Navy's underwater warfare capabilities.
These submarines are based on the internationally proven Scorpène-class design and have been constructed in India through a technology-transfer program. Beyond adding new submarines to the fleet, the project has significantly expanded India's expertise in designing, building, integrating, and maintaining complex naval platforms.
The Kalvari-class was developed for a wide range of missions, including intelligence gathering, maritime surveillance, anti-submarine warfare, anti-surface warfare, mine-laying, and special operations.
Unlike large nuclear-powered submarines that are intended for long-duration strategic patrols, these conventional submarines are optimized for stealth, flexibility, and effectiveness in regional waters.
Their compact design allows them to operate efficiently in coastal and littoral environments where remaining undetected is often more important than sheer size or speed.
This makes them well suited for the operational requirements of the Indian Ocean Region.
What Makes These Submarines So Difficult to Detect?
Stealth is one of the most valuable qualities of any modern submarine.
A submarine that can remain undetected has a significant operational advantage because it can observe, gather intelligence, and respond to threats without revealing its own position.
Project 75 places considerable emphasis on reducing the submarine's acoustic signature, which is the amount of sound it produces underwater.
Every rotating component inside a submarine—from propulsion systems to pumps and machinery—can generate noise that may be detected by sophisticated sonar systems.
To minimize this risk, engineers employ advanced vibration isolation techniques, precision engineering, sound-dampening materials, and streamlined hull designs.
The hull is carefully shaped to reduce hydrodynamic resistance while improving underwater efficiency.
Internal equipment is mounted in ways that limit the transmission of vibrations through the submarine's structure.
Together, these engineering improvements make the submarine quieter and significantly more difficult to locate during underwater operations.
Modern sonar systems, electronic support measures, and integrated combat management software further enhance situational awareness while allowing the crew to detect potential threats without unnecessarily exposing their own position.
Advanced Combat Systems and Weapon Capabilities
Modern submarines are no longer simply underwater vessels carrying torpedoes.
They have evolved into sophisticated combat platforms equipped with advanced sensors, digital processing systems, and highly integrated mission management technologies.
The Kalvari-class incorporates an advanced combat management system that combines information from sonar arrays, navigation equipment, communication systems, and other onboard sensors into a unified operational picture.
This integration enables commanders to evaluate tactical situations more quickly and make informed decisions during complex naval operations.
The submarines are designed to deploy heavyweight torpedoes against hostile submarines and surface warships.
They are also capable of launching anti-ship missiles, giving them the ability to engage enemy vessels from significant distances while remaining concealed beneath the sea.
In addition, these submarines can support intelligence missions, surveillance patrols, and special operations, making them valuable assets during both peacetime and conflict.
Rather than serving only as offensive platforms, they also contribute to maritime deterrence by increasing uncertainty for potential adversaries about their location and operational readiness.
Why Is Air-Independent Propulsion (AIP) So Important?
One of the most significant technological upgrades associated with the future evolution of Project 75 is Air-Independent Propulsion (AIP).
Traditional diesel-electric submarines must periodically surface or use a snorkel to operate diesel engines and recharge their batteries.
Although effective, this process increases the possibility of detection.
AIP technology addresses this limitation by allowing submarines to remain submerged for much longer periods without requiring atmospheric oxygen for propulsion-related power generation.
Longer underwater endurance provides greater operational flexibility during surveillance missions, intelligence gathering, and strategic patrols.
It also improves survivability because the submarine spends less time near the surface, where it is more vulnerable to modern surveillance systems.
As underwater detection technologies continue advancing, extended submerged endurance has become one of the defining characteristics of next-generation conventional submarines.
For this reason, AIP is widely regarded as one of the most important technologies shaping the future of non-nuclear submarine operations.
What Is Project 75(I) and Why Does It Matter?
While Project 75 has significantly strengthened the Indian Navy's conventional submarine fleet, it is only one phase of India's long-term underwater modernization strategy.
The next major step is Project 75(I), a planned program to acquire a new generation of advanced conventional submarines equipped with technologies designed for the evolving challenges of modern naval warfare.
Although procurement plans continue to evolve, the objective remains clear: enhance underwater endurance, improve stealth, integrate advanced sensors and combat systems, and expand indigenous manufacturing capabilities.
One of the most anticipated features associated with Project 75(I) is the incorporation of Air-Independent Propulsion (AIP) technology. By enabling submarines to remain submerged for extended periods, AIP reduces the need to surface frequently, improving survivability during surveillance and combat missions.
The program also places strong emphasis on technology transfer and domestic industrial participation. Rather than simply purchasing military platforms, India aims to strengthen its long-term capability to design, manufacture, maintain, and upgrade complex naval systems within the country.
This approach aligns with the broader objective of building a more self-reliant and technologically advanced defense manufacturing ecosystem.
Why Is Project 75 Important for the Indo-Pacific?
The Indo-Pacific has become one of the world's most strategically significant maritime regions.
It contains some of the busiest international shipping lanes, major energy transportation routes, and critical economic corridors connecting Asia, Europe, Africa, and the Middle East.
Maintaining maritime security in this region requires continuous surveillance, credible deterrence, and the ability to respond quickly to emerging challenges.
Modern submarines contribute to these objectives because they can operate discreetly for long periods while monitoring maritime activity without revealing their location.
For India, Project 75 strengthens underwater situational awareness, enhances sea-denial capability, supports intelligence collection, and improves operational flexibility across the Indian Ocean Region.
Rather than serving only during conflict, submarines also play an important role in maintaining stability during peacetime through surveillance, presence, and deterrence.
As naval technologies continue evolving, underwater platforms are becoming increasingly integrated with satellite communications, network-centric operations, advanced sonar systems, unmanned underwater vehicles, and artificial intelligence–assisted decision support.
Project 75 therefore represents not only a fleet modernization program but also a foundation for India's future underwater warfare capabilities.
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Future Technologies Shaping Next-Generation Submarines
The future of conventional submarines extends well beyond propulsion systems.
Artificial intelligence is expected to assist crews in processing large volumes of sonar data, identifying underwater contacts, and improving situational awareness.
Advanced battery technologies may provide greater underwater endurance while supporting quieter operations.
New composite materials and improved hull designs could further reduce acoustic signatures, making submarines even more difficult to detect.
Autonomous underwater vehicles may eventually operate alongside crewed submarines, extending surveillance range and supporting mine countermeasures, reconnaissance, and environmental monitoring.
Cybersecurity is also becoming increasingly important as modern submarines rely on highly integrated digital combat systems and secure communications.
Future submarine operations are therefore expected to combine stealth, automation, intelligent sensors, and advanced networking to create highly capable underwater platforms for decades to come.
Final Thoughts
Project 75 represents one of the most important milestones in the modernization of the Indian Navy's conventional submarine fleet.
Beyond introducing the Kalvari-class submarines, the program has strengthened India's shipbuilding expertise, encouraged technology transfer, and supported the growth of indigenous defense manufacturing.
Its importance extends beyond national defense. Project 75 reflects how modern naval warfare increasingly depends on stealth, advanced engineering, digital combat systems, and underwater situational awareness rather than numerical fleet size alone.
As India continues developing future capabilities through initiatives such as Project 75(I), Air-Independent Propulsion, advanced sensors, and next-generation underwater technologies, its submarine force is expected to play an increasingly significant role in ensuring maritime security across the Indo-Pacific.
Understanding Project 75 provides valuable insight into how technological innovation, strategic planning, and industrial capability are shaping the future of modern naval warfare.Technology.
