48.5 kN Kaveri Engine Completes Another Major Flight Test

India’s non-afterburning Kaveri-derivative engine, developed by the Gas Turbine Research Establishment (GTRE) under the DRDO, has completed a major phase of flight evaluation in Russia.

The engine is derived from the original GTX-35VS Kaveri turbofan, which was initially developed to power the LCA Tejas but was later redirected to other applications after it fell short of the thrust and performance requirements for a fighter aircraft.

The non-afterburning derivative is primarily intended to power India’s Ghatak stealth unmanned combat aerial vehicle (UCAV), which is associated with the country’s Remotely Piloted Strike Aircraft programme. Officially cited dry-thrust targets for the engine are in the 49–51 kN range.

Russian Flight Testing

The engine underwent testing at Russian facilities, including the Central Institute of Aviation Motors (CIAM) and the Gromov Flight Research Institute. Engineers evaluated its performance across different atmospheric pressures, Mach numbers and high-altitude conditions, including simulated environments equivalent to around 13,000 metres.

For real-flight testing, the engine was installed on a modified Ilyushin Il-76 flying testbed, replacing one of the aircraft’s standard engines.

Reports indicate that the Russian flight-evaluation phase has now been completed, with the collected data expected to undergo further analysis in India.

However, the programme is not yet at the final qualification stage. Certification involving agencies such as CEMILAC, along with further integration work for the Ghatak UCAV, remains to be completed.

It is also worth noting that an earlier high-altitude and flight-test campaign involving the Il-76, conducted around 2022 and early 2023, had already reported a peak dry thrust of approximately 48.5 kN. Recent reports therefore appear to relate to the completion or continuation of subsequent evaluation phases rather than an entirely new test campaign.

The latest development represents another step forward for India’s indigenous aero-engine programme and the Ghatak UCAV. However, peak thrust alone does not determine an engine’s operational readiness. Further qualification will need to establish parameters such as reliability, endurance, fuel efficiency and overall performance under operational conditions.