Kaveri Dry Engine Reported to Clear Russian Trials at 48.5 kN, With Certification Ahead
September reporting says DRDO's GTRE Kaveri dry engine completed Russian trials with 48.5 kN peak dry thrust. CEMILAC certification and integration with the planned Ghatak UCAV remain ahead; the report does not establish operational deployment.
India's long-troubled Kaveri jet engine is back in the headlines. Reports this week say the dry, non-afterburning version of the engine, built by DRDO's Gas Turbine Research Establishment (GTRE), has finished high-altitude and flying-testbed trials in Russia. It reportedly delivered a peak dry thrust of 48.5 kilonewtons, beating its target of about 46 kN.
If the reported completion is confirmed, the next demanding phase is: airworthiness certification and integration with Ghatak, India's planned stealth unmanned combat aerial vehicle (UCAV).
What the trials involved
According to the reports, the engine was tested at two Russian facilities:
- The Central Institute of Aviation Motors (CIAM), whose altitude test cells can simulate the thin, cold air an engine meets at cruise altitude. Earlier campaigns there simulated conditions up to about 13,000 metres.
- The Gromov Flight Research Institute, where a modified Ilyushin Il-76 served as a flying testbed. One of the aircraft's four standard engines was replaced with the Kaveri, so the engine could be tested in real flight while the other three engines provided a safety margin.
Flying-testbed trials matter because ground rigs cannot fully reproduce real flight: changing intake airflow, manoeuvre loads, and repeated throttle changes at altitude. Those trials inform the separate certification and aircraft-integration work that follows.
The 48.5 kN figure itself is not new. Earlier high-altitude tests in Russia, reported in October 2022 and February 2023, also recorded 48.5 kN of dry thrust. This week's reports present the Russian campaign as complete and the engine as ready for the next step.
The numbers in context
How much is 48.5 kN? It is well below the roughly 84 kN that the Tejas's GE F404 produces with its afterburner lit, and that gap in fighter-class thrust is why Kaveri was pulled off Tejas. For a dry engine driving a subsonic stealth drone, though, the figure is in the right range. The reported peak is about 5% above 46 kN, but usable installed thrust depends on the intake, operating conditions and certification envelope.
A programme with a long history
The Kaveri (formally the GTX-35VS) began in the late 1980s as an afterburning turbofan to power the HAL Tejas light combat aircraft. The programme struggled to meet thrust and weight targets on time. In September 2008 it was officially delinked from Tejas, which went on to fly with General Electric's F404 engine.
GTRE did not shelve the engine. Instead, it redirected the core towards a dry variant without the afterburner, sized for a subsonic unmanned aircraft. That is the variant discussed in the current reports. It suits a stealth UCAV well. Ghatak is designed to fly at high subsonic speeds with a low radar signature. Its mission profile does not need a supersonic dash, and dropping the afterburner also reduces the engine's infrared signature.
What comes next: CEMILAC and Ghatak
The next steps are:
- Certification by CEMILAC, the Bengaluru-based Centre for Military Airworthiness and Certification. CEMILAC must approve the engine's safety and endurance before it can power an Indian military aircraft.
- Installed-condition trials, in which the engine is tested as it would be mounted in Ghatak, with its curving, radar-shielding air intake and buried exhaust.
- Flight trials with the Indian Air Force as part of the Ghatak programme.
Reports suggest the engine could be fully ready in about two to three years if certification and integration go well. Ghatak is a tailless flying-wing design. Its engine has to breathe through a serpentine intake that hides the fan face from radar. At Aero India 2019, GTRE showed a Kaveri model adapted for exactly that kind of intake.
Why it matters for India
Aero-engines are among the hardest technologies to build, and India’s fighter fleet relies substantially on foreign-designed engines. That leaves India exposed to export licences, supply delays and upgrade cycles it does not control.
A certified dry Kaveri would not close that gap for fighter jets. India is pursuing a separate, more powerful engine for its next-generation fighters through cooperation with foreign engine makers. But it would give India:
- A sovereign engine for unmanned combat aircraft, a class that recent conflicts have made central to air power.
- Real certification experience. CEMILAC and GTRE would take an Indian-designed engine through a full military airworthiness process, which India's future engine programmes also need.
- A base for derivatives. A proven dry core can be adapted for other drones, trainers or even industrial and marine gas-turbine uses.
There is also an industrial angle. GTRE's engines are only as good as the castings, forgings, single-crystal blades and coatings behind them. A Kaveri moving towards production would create steady demand for Indian suppliers in metallurgy and precision manufacturing, areas India has identified as strategic gaps.
A note of caution
The Kaveri has had false dawns before, and thrust is only one measure of a usable engine. Weight, fuel consumption, reliability over thousands of hours, and how the engine behaves with Ghatak's stealth intake will decide whether it enters service. Certification is where many engine programmes slip.
Still, after nearly four decades, the Kaveri now has a clear path to an aircraft it was effectively redesigned for. For India's defence-technology base, that counts as real progress.
Sources
Reporting note: the current completion and thrust claims are attributed to September reporting, including NewsBytes on 30 September. This article does not establish a new official GTRE test release, certification or operational deployment.
Image: DRDO official emblem, used to identify the organisation. It does not depict the Kaveri engine or a Russian trial. Original source.