For over three decades, India chased a dream it couldn’t quite catch: building a jet engine of its own. The original Kaveri project, once seen as a national milestone, became a cautionary tale of delays, technical roadblocks, and abandoned ambitions.
But in 2025, everything changed.
GTRE, a DRDO lab long written off, unveiled the Kaveri Derivative Engine with afterburner. This is not a concept or CGI render. It is a working prototype, now cleared for manned flight trials on a Tejas LSP aircraft. For the first time, an Indian fighter is set to fly with an Indian afterburning engine.
What makes this engine different? Why now? And could this be the start of true self-reliance in fighter jet propulsion?
Let us unpack what has changed and why it matters more than ever.
Introduction: From Failure to Flight – The Kaveri Engine Story
India’s dependence on foreign jet engines has long been a strategic vulnerability. While the Tejas Mk1A continues to rely on the GE F404-IN20, the Mk2 will adopt the GE F414. The long-term vision has always been to build a completely indigenous fighter jet engine.
GTRE’s latest reveal changes the equation. The Kaveri Derivative Engine with afterburner is the most advanced indigenous engine India has ever publicly demonstrated. Unlike its predecessor, this one is purpose-built for unmanned platforms and testbed aircraft, not for frontline fighters – yet.
DRDO Kaveri Engine Latest Update: Certified, Tested, Ready to Fly
After years of low visibility, the Kaveri programme has quietly matured into something tangible. GTRE showcased the engine’s hot section, nozzle configuration, and wiring during its public reveal.
Key Performance Parameters:
- Dry thrust: 49 to 52 kilonewtons (kN)
- Afterburner thrust: 73 to 80 kN
- Remaining testing time: Less than 25 hours
- Planned platforms: Ghatak UCAV, Tejas LSP (Limited Series Production) aircraft for test flights
This thrust rating brings the KDE close to the performance of the GE F404, which powers the Tejas Mk1A. That alone is a massive achievement for India’s aero engine development ecosystem.
Why the Kaveri Engine Is Not Going Into Tejas
A frequent question is: Will the Kaveri derivative engine power Tejas? The short answer is no – at least not yet.
Reasons It’s Not Going Into Tejas (Yet):
- The Kaveri Derivative is optimised for testbeds and drones, not frontline squadrons
- The original Kaveri couldn’t meet high-altitude thrust and thermal demands
- Tejas Mk1A and Mk2 are committed to GE F404 and F414 engines
What’s New in 2025:
- In September 2025, GTRE partnered with HAL to integrate the afterburner-equipped KDE into a Tejas LSP aircraft.
- After successful simulation trials, the Indian Air Force approved manned flight testing of this indigenous engine.
- While it won’t replace GE engines yet, this is the first Indian afterburning engine to be flight-tested on a manned fighter platform, a major milestone toward future certification.
Also Read: 97 Additional Tejas Mk1A Jets Ordered: Why GE F404 Still Dominates
Public Confusion: No, This Engine Is Not for Tejas
When GTRE unveiled the Kaveri Derivative Engine with afterburner, it created quite a buzz on social media and defence forums. Many assumed this was the long-awaited replacement for the GE-F404 powering the Tejas Mk1A or the GE-F414 planned for Tejas Mk2.
But the reality is very different.
This engine is not meant for Tejas. It is not yet certified for manned fighters, nor does it meet the thrust and reliability standards required for combat deployment in frontline jets.
Instead, it is purpose-built for:
- Ghatak UCAV (India’s stealth unmanned combat drone)
- Tejas LSP aircraft for flight-testing and data collection only
The public excitement is understandable, but it’s important to fact-check the role and limitations of this engine in 2025. While it’s a breakthrough, it’s not a drop-in replacement for existing Tejas engines.
Flight Test Plan Begins in 2025
In a major leap for India’s engine programme, GTRE has roped in HAL to begin integration of the Kaveri Derivative Engine with afterburner into a Tejas LSP aircraft.
What’s Planned:
- Ground trials to validate safety and thermal performance
- Taxi trials to test throttle and control response
- Manned flight tests, approved by the IAF after simulation data
This will be the first Indian afterburning engine to fly on a manned fighter platform, a major milestone for indigenous propulsion.
Real-World Applications: India’s Jet Engine for UCAV and Future Systems
The Kaveri Derivative Engine is not a dead-end. It is a cornerstone of India’s defence propulsion strategy moving forward.
Confirmed Integration: Ghatak UCAV
- The engine is tailored for the Ghatak Unmanned Combat Aerial Vehicle (UCAV).
- With a dry thrust of approximately 52 kN, it is ideal for stealth drones that prioritise endurance and low infrared signature.
- Its integration will make Ghatak the first Indian UAV powered by an indigenous turbofan engine.
Potential Future Roles:
- It may be used in indigenous trainer aircraft or light combat platforms.
- Will support the development and validation of future propulsion systems.
- Acts as a tech demonstrator for modular engine architectures.
This is India’s first serious step toward a jet engine for Indian stealth drones, built entirely within the country.
Also Read: Ghatak UCAV: India’s Stealth Drone Powered by Kaveri
Engineering Breakthrough: Afterburner Integration in Indigenous Engine
Until now, India had never publicly demonstrated a fully integrated afterburner-equipped Indian engine.
What This Proves:
- Successful fuel injection and flame stability under variable conditions
- Reliable nozzle actuation and thrust modulation
- Capability to handle high thermal loads using indigenous alloys and coatings
GTRE has shown it can meet complex fighter-class engine thrust levels with an Indian core – and that is the real headline.
Dry Thrust vs Afterburner Thrust: Why Both Matter
Understanding the difference is crucial:
- Dry thrust is used during cruising, loitering, and stealthy missions.
- Afterburner thrust is used during takeoff, supersonic acceleration, or combat manoeuvres.
With thrust scaling from 49 kN to nearly 80 kN, the KDE gives Indian platforms the tactical flexibility previously limited to imported systems.
Performance Comparison: GTRE Kaveri Derivative vs GE F404
| Specification | Kaveri Derivative Engine | GE F404-IN20 (Tejas Mk1A) |
|---|---|---|
| Dry Thrust | 49–52 kN | 53.9 kN |
| Afterburning Thrust | 73–80 kN | 78.7 kN |
| Engine Control | Likely Digital FADEC | Full FADEC |
| Certification | Pending test flights | Fully operational |
| Platforms | Ghatak, Tejas LSP | Tejas Mk1A |
While the GE engine is combat-tested, India’s homegrown option is now within striking distance.
The Road Ahead: GTRE–Safran Engine for AMCA Mk2
The Kaveri Derivative Engine is not the endgame. It is a stepping stone toward GTRE’s next big goal – a 110+ kN class engine for fifth-generation fighters.
India’s Collaboration with Safran Includes:
- Co-development of an engine for the AMCA Mk2
- Full technology transfer (ToT) to enable Indian manufacturing
- Use of advanced single-crystal blades, digital control systems, and high-temperature materials
With this programme, India may finally move toward a truly independent fighter jet engine ecosystem.
Also Read: AMCA MkII Engine: GTRE–Safran Jet Engine Deal Explained
Timeline: India’s Jet Engine Journey at a Glance
| Year | Milestone |
|---|---|
| 1989 | Kaveri engine project launched by DRDO |
| 2006 | First prototype tested in Russia |
| 2014 | Kaveri tested again, but still fell short |
| 2022 | Kaveri Derivative Engine (KDE) programme launched for UAVs |
| 2025 | GTRE unveils afterburner-equipped KDE prototype |
| 2025 | HAL begins KDE integration with Tejas LSP |
| 2026 | Ground, taxi, and manned flight trials to begin |
| 2032 | Safran–GTRE engine planned for AMCA Mk2 |
My Perspective: Why This Development Actually Matters
As someone who has followed India’s aerospace evolution for years, I see this as more than a milestone. It is a moment of course correction.
The original Kaveri programme failed, but GTRE did not give up. Instead, they recalibrated, learned from setbacks, and delivered a system that works, one that is already being prepped for flight testing on the Tejas LSP.
With this engine, India does not just build thrust. It builds credibility, especially as the country prepares to fly a manned fighter jet powered by an Indian afterburning engine for the first time.
Frequently Asked Questions (FAQs)
Q1. Will the Kaveri engine power Tejas?
No. Tejas Mk1A and Mk2 will continue using GE engines. The KDE is not yet certified for manned fighter roles.
Q2. Which aircraft will use the Kaveri derivative engine?
It will first power the Ghatak UCAV and later be used in Tejas LSP testbeds.
Q3. What is the thrust of the Kaveri derivative engine?
Dry thrust: 49–52 kN. With afterburner: 73–80 kN.
Q4. Can this engine be exported?
Once certified, it may be offered to friendly nations for drones or trainers under Make in India.
Q5. How does this support engine self-reliance?
It gives India independent propulsion capability for critical platforms, reducing dependency on imported engines.
Q6. Is the Kaveri Derivative Engine with afterburner being tested on Tejas?
Yes. In 2025, GTRE and HAL began integrating it into a Tejas LSP. The IAF approved manned flight trials after simulation tests.