The Gas Turbine Research Establishment (GTRE), under the Defence Research and Development Organisation (DRDO), has revealed the first look of the fully integrated Kaveri Derivative Engine (KDE), also known as the Kaveri Dry Engine, paired with the Advanced Full Authority Digital Engine Control Unit (AFADECU).

This milestone marks a pivotal advancement in India's indigenous turbofan engine program, designed specifically to power the First Vehicle of the Remotely Piloted Strike Aircraft (RPSA).

The black-and-white image showcases the engine's intricate assembly, highlighting exposed turbine sections, fuel lines, and control modules, underscoring its readiness for ground and flight testing.

The KDE is a non-afterburning variant of the original GTX-35VS Kaveri turbofan, optimised for unmanned combat aerial vehicles (UCAVs) like the DRDO Ghatak and now the RPSA.

It employs a single-spool configuration with a four-stage axial flow compressor, annular combustor, single-stage uncooled turbine, and fixed exit nozzle, delivering approximately 49-51 kN of dry thrust.

Recent ground tests have validated its performance across full throttle ranges, achieving stable outputs near 50 kN, with enhancements including a redesigned fan for inlet pressure distortion tolerance suited to serpentine intakes on stealth platforms.

The Kaveri Dry Engine (KDE) integrates an advanced, indigenous AFADECU as its digital brain, boosting control, performance, and stealth. Developed by GTRE, this dual-lane digital control system has been qualified, integrated, and inducted into the program as of late 2025/early 2026. It eliminates manual backups with seamless redundancy, real-time health monitoring, fault detection, and care-free throttle handling.

This system monitors vibrations, temperatures, and thermal patterns, preventing issues like engine flame-outs while reducing weight and fuel consumption through automated adjustments. Over 1,300 hours of testing, conducted in collaboration with Safran, have confirmed its reliability across diverse conditions.

The RPSA, developed by DRDO's Aeronautical Development Establishment (ADE), is a stealthy remotely piloted strike aircraft featuring low radar cross-section (RCS) design, internal weapons bays, and AI-driven autonomy for network-centric warfare.

The KDE's subsonic thrust profile suits the platform's emphasis on endurance, stealth, and operational flexibility rather than high-speed dogfighting, with a lower infrared signature enhancing survivability. This integration positions the First Vehicle as a low-cost collaborative combat aircraft (CCA) demonstrator.

Development partners have accelerated production: Godrej delivered the first two KDE prototypes in April 2025, with six more underway, while Azad Engineering serves as the primary industry collaborator for manufacturing critical components like titanium oil tanks and 3D-printed anti-icing assemblies. High-altitude simulations in Russia validated prototypes, including a new fan module and short jet pipe, paving the way for in-flight trials on a modified Ilyushin Il-76 by late 2025 or early 2026.

This achievement revives the Kaveri program after decades of challenges, including thrust shortfalls in the full wet variant, by focusing on proven dry configurations for UAVs ahead of manned applications like TEJAS MK-2 or AMCA.

GTRE's new 130 kN test facility nearing completion will enable domestic refinement, targeting full certification and Ghatak integration by 2026.

The RPSA-KDE pairing promises to bolster India's unmanned strike capabilities, reducing reliance on foreign engines and fostering a self-reliant aerospace ecosystem.

IDN (With Agency Inputs)