New Delhi: Indian Navy additional submarines plans are gaining attention as the Ministry of Defence evaluates the acquisition of three more conventional submarines to strengthen India’s underwater combat capability. The move is being considered as a bridge solution until the indigenous Project-76 submarine program becomes operational.
The Navy is reportedly studying two options: adopting the advanced Project-75I design or building an upgraded version of the successful Kalvari-class submarines already in service.
Project-75I: Why Does the Indian Navy Need More Submarines?
India’s submarine fleet faces growing operational pressure due to increasing maritime competition in the Indian Ocean Region.
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Key reasons include:
- Maintaining underwater deterrence capabilities.
- Replacing ageing conventional submarines.
- Countering expanding Chinese naval presence in the Indian Ocean.
- Ensuring uninterrupted operational readiness until Project-76 submarines enter service.
According to defence experts, India’s conventional submarine force requires modernization to address capability gaps and future security challenges.
Option 1: Project-75I Technology-Based Submarines
The first option under consideration is leveraging the upcoming Project-75I submarine design.
Project-75I Highlights
- Six next-generation conventional submarines are planned under the project.
- Partnership involves Germany’s TKMS and India’s Mazagon Dock Shipbuilders Limited (MDL).
- Estimated project value is around ₹70,000 crore.
- Features advanced Air Independent Propulsion (AIP) technology.
- Enables submarines to remain underwater for significantly longer periods.
- Expected to offer improved stealth, endurance and combat performance.
Strategic Benefits
- Access to cutting-edge submarine technology.
- Enhanced underwater endurance due to AIP systems.
- Greater operational flexibility in long-duration missions.
- Strong technology transfer opportunities for India’s submarine industry.
Option 2: Advanced Kalvari-Class Submarines
The second option is building an upgraded version of the Kalvari-class submarines already produced in India under Project-75.
Why Kalvari Is Attractive
- Existing production infrastructure already available.
- Skilled workforce and supply chain already established.
- Lower development risks.
- Faster delivery schedules.
- Potentially lower costs than introducing a completely new design.
Possible Upgrades
The Advanced Kalvari variant could include:
- Improved combat management systems.
- Enhanced sonar and sensor suites.
- Better battery technology.
- Increased indigenous content.
- Future integration of indigenous AIP technology.
Project-75I vs Advanced Kalvari: Quick Comparison
| Feature | Project-75I | Advanced Kalvari |
| Technology Level | New-generation | Proven platform with upgrades |
| Development Risk | Moderate to High | Low |
| Construction Speed | Slower | Faster |
| Cost | Higher | Lower |
| Technology Transfer | Extensive | Limited |
| Production Ecosystem | To be expanded | Already established |
| Operational Maturity | Future platform | Proven operational record |
What Makes This Decision Important?
The Indian Navy is trying to balance:
- Immediate operational requirements.
- Budget efficiency.
- Indigenous defence manufacturing goals.
- Long-term technological superiority.
Choosing Project-75I would provide access to advanced technologies and future-ready capabilities. Choosing Advanced Kalvari would ensure quicker fleet expansion with lower risk and better utilization of existing infrastructure.
Link to India’s Project-76 Vision
India’s long-term submarine roadmap revolves around Project-76, an indigenous submarine program expected to incorporate advanced stealth features and homegrown technologies.
Recent developments indicate that Project-76 is becoming a major pillar of India’s self-reliance strategy in naval warfare. The additional three submarines being considered now could serve as a critical stop-gap capability until Project-76 enters production.
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