India’s indigenous Kaveri Derivative Engine has reportedly completed high-altitude and in-flight trials in Russia, a step toward powering the proposed Ghatak stealth UCAV. Reports say the evaluation used an Ilyushin Il-76 flying test-bed with the Kaveri fitted in place of one of its standard engines. One report puts peak thrust at 48.5 kN, and another says this exceeded the 46 kN target set for the UCAV application. These figures come from news citing reports, not from an official DRDO or GTRE release. The engine must still complete certification, platform integration and UCAV flight testing.
The programme has been moving on several fronts. In March 2026, a report said the Defence Procurement Board had recommended acquiring 60 Ghatak UCAVs, though the Defence Acquisition Council still has to approve it. The Ministry of Defence has sanctioned ₹472.42 crore for a flightworthy Kaveri Dry Engine and ₹251.17 crore for technology demonstration, about ₹723 crore in total. On the testing side, the First Engine To Test was integrated in July 2025 and uninstalled-condition trials are complete, and it is now being rebuilt for installed-condition demonstrations. Godrej Aerospace was tasked with building six derivative engines and delivered the first two modules to GTRE in April 2025. The Ghatak itself is expected to cruise near Mach 0.9, operate at altitudes up to 40,000 feet and carry precision-guided munitions over ranges exceeding 1,000 kilometres.
Analysis: what Kaveri was meant to be
GTRE began the Kaveri (GTX-35VS) in the late 1980s to power the Tejas. It was sanctioned with an initial budget of ₹382.21 crore, and the real cost grew many times over. The target was a low-bypass afterburning turbofan of roughly 81 kN wet and about 52 kN dry, which is the class of engine the Tejas Mk1 was designed around.
From memory, and worth verifying, the Kaveri never reliably reached its wet-thrust target. Its best demonstrated figures were roughly 70 to 75 kN with afterburner. That was well short of the goal and of the roughly 84 to 90 kN offered by the GE F404 and F414 family. The Tejas Mk1 and Mk1A fly on the F404, and the Mk2 is designed around the more powerful F414.
The usual explanations for the shortfall are technological and organisational. India lacked mature single-crystal turbine blade capability, which is needed to sustain high turbine inlet temperatures. The engine was also heavier than the airframe design assumed. There was no high-altitude test facility in India, so trials had to be done in Russia, and few engines were built to iterate on. The collaboration with France’s Snecma, now Safran, did not produce a finished engine either. The engine was formally delinked from the Tejas programme in 2008.
The dry variant makes sense because the Ghatak is a subsonic flying wing and does not need an afterburner, which removes the hardest part of the original design. Its reported 46 to 52 kN class is close to what the core was originally meant to deliver dry. In effect, the engine is now being given a job it can actually do. The dry engine also incorporates an indigenously designed fan tolerant of high inlet distortion, a fuel-control system, an autonomous engine-control system and a short jet pipe, all useful for a stealth drone.
There are caveats. The reported 48.5 kN is a test-bed number, not a certified one, and a combat drone engine also needs proven reliability and a low infrared signature. A true fighter-class engine is a much bigger leap. Kaveri 2.0 or an AMCA-class engine of 110 to 120 kN is expected to depend on foreign co-development, with Safran the partner most often discussed. Even so, the Kaveri programme has given India engine integration, endurance testing and materials experience that it did not have before.
