India's Dry Kaveri Engine with New Afterburner Moves Closer to Flight Testing on LCA-Tejas

India’s quest for indigenous fighter jet engine technology has taken a significant leap forward. The Gas Turbine Research Establishment (GTRE), a key wing of the Defence Research and Development Organisation (DRDO), has received approval to integrate the Dry Kaveri engine—enhanced with a newly developed afterburner—into an older variant of the Light Combat Aircraft (LCA)-Tejas for flight validation. This breakthrough reflects decades of perseverance in developing a homegrown engine that can eventually reduce India’s dependence on foreign suppliers for military aviation needs.

Originally conceived for unmanned systems like DRDO's Ghatak stealth UCAV, the Dry Kaveri is a non-afterburning version of the Kaveri engine. It has recently shown encouraging results in ground testing, generating 49-50 kilonewtons (kN) of thrust—exceeding its earlier target of 46 kN. With the development of a new afterburner module, GTRE aims to further boost thrust to nearly 80 kN. This is a significant step forward when compared to the 73-75 kN thrust generated in earlier Kaveri engine demonstrations. With this added capability, the engine could potentially power manned fighter jets like the LCA-Tejas Mk1A, which currently relies on the imported GE F404-IN20 engine that produces 78.7 kN of thrust with afterburner.

The development of the afterburner is still ongoing. GTRE is in the process of procuring specialized materials required to withstand high temperatures and stress. The successful integration of this module would not only improve overall thrust but also bring performance closer to modern fighter jet engines currently in use.

For flight testing, GTRE is preparing to install the upgraded Dry Kaveri engine into an older Limited Series Production (LSP) Tejas aircraft. Two prototypes—PV-5 (KH-T2009) and PV-6 (KH-T2010), originally developed for the twin-seater Tejas variant—are being considered for this milestone task. However, the Indian Air Force has raised caution over using a single-engine fighter for early-stage trials of an unproven engine. It has suggested safer alternatives, such as using a twin-engine platform or an unmanned flying testbed. Despite these concerns, GTRE seems committed to leveraging the existing LCA-Tejas platform for in-air validation, potentially using its earlier flight data as a safety benchmark.

The bigger picture here is strategic. If the Dry Kaveri engine with the new afterburner performs well during flight testing, it could pave the way for future integration into Tejas Mk1A aircraft. This would make the Tejas fleet even more indigenous and reduce reliance on foreign powerplants like those from the United States. The next iteration of the engine, often referred to as Kaveri 2.0, is expected to deliver even more thrust—up to 83-85 kN—putting it firmly in competition with the F404 family.

While flight testing in India is progressing, GTRE has also partnered with Russia for high-altitude testing and integration trials. Final testing will take place aboard a modified Ilyushin Il-76 aircraft at Russia’s Gromov Flight Research Institute. This Flying Test Bed (FTB) will replace one of its four engines with the Dry Kaveri to assess how the engine performs under real-world flight conditions. These trials are scheduled to begin in September 2025, building on previous successful tests conducted in 2022 and 2023, where the engine exceeded its target dry thrust benchmarks.

If all goes well, GTRE aims to complete these trials by 2025 and begin limited production by 2025-26, initially for unmanned systems like the Ghatak UCAV. The Indian defense establishment is optimistic that the improved engine, once proven, can also power manned platforms and open new avenues for India's indigenous fighter development programs.

Still, challenges remain. The current weight of the Dry Kaveri engine—about 1,180 kilograms—is higher than that of its competitors like the GE F404 (1,036 kg) or even the more powerful F414 (1,110 kg). This weight difference could impact the LCA-Tejas’s agility and fuel efficiency. To address this, GTRE is collaborating with Indian manufacturers like MIDHANI to develop lighter and stronger materials. Metallurgical and thermal challenges related to the afterburner are also being addressed through advanced manufacturing methods and design optimizations.

The integration of the Kaveri engine into the LCA-Tejas is more than just a technological upgrade—it is a symbolic stride towards self-reliance in high-end aerospace propulsion. If successful, it will not only bolster the capabilities of India’s fighter aircraft but also enhance the country’s strategic autonomy in defense manufacturing.