India's ambitious quest for self-reliance in aero-engine technology has encountered significant hurdles, as highlighted by Defence Research and Development Organisation (DRDO) chief Samir V. Kamat.

The Kaveri engine, India's first indigenous jet engine program, was officially delinked from the Light Combat Aircraft (LCA) TEJAS program in 2008 due to persistent performance shortfalls.

DRDO chief Samir V Kamat confirmed the engine will be adapted, without its afterburner, to power the nation's upcoming unmanned combat aerial vehicles.

Despite years of development, the Kaveri engine in its original configuration has failed to meet the thrust requirements of the TEJAS. Kamat confirmed that while the engine now delivers a respectable 72 kilonewtons (kN) of thrust, the TEJAS demands between 83 and 85 kN for optimal performance. This gap has rendered it unfit for manned fighter operations.

The DRDO views this limitation not as a defeat, but as a pivot towards alternative applications. Kamat emphasised that a derivative of the Kaveri, stripped of its afterburner, will power India's upcoming unmanned combat aerial vehicles (UCAVs). This adaptation leverages the engine's dry thrust capabilities for drone platforms where high afterburning performance is unnecessary.

Engine development remains a protracted endeavour worldwide, Kamat noted. He pointed out that even leading global programs require 10 to 13 years to mature before platform integration. India's experience with Kaveri aligns with this timeline, underscoring the complexities of turbofan technology.

Looking ahead, Kamat outlined a realistic roadmap for next-generation engines. Should the Cabinet Committee on Security (CCS) approve funding this year, he anticipates the new engine will be ready for integration by 2035-2036. Development trials would precede this, with final acceptance trials commencing around that period.

In the interim, India's fifth-generation Advanced Medium Combat Aircraft (AMCA) will rely on foreign powerplants. The first two squadrons are slated for delivery with General Electric F414 engines, ensuring no delays in operational timelines while indigenous efforts mature.

This strategic shift reflects broader priorities in India's defence research ecosystem. Kamat affirmed that aero-engines and UCAVs will remain focal points. The DRDO is also advancing deep technologies essential for future systems, including quantum technologies, artificial intelligence and machine learning (AI/ML), and advanced materials.

These innovations will permeate all upcoming platforms, enhancing performance and indigenisation. For instance, AI/ML could optimise engine controls, while quantum tech might bolster secure communications in combat environments. Advanced materials promise lighter, heat-resistant components critical for high-thrust engines.

The Kaveri program's evolution mirrors India's defence journey: from early setbacks to adaptive resilience. Originally conceived in the 1980s under the Gas Turbine Research Establishment (GTRE), it aimed to reduce dependence on imported engines like the GE F404 powering current TEJAS variants.

Challenges have been multifaceted. Metallurgical issues, particularly with single-crystal turbine blades, plagued early tests. Compressor inefficiencies and afterburner instability further delayed progress. International collaborations, including with France's Snecma (Renamed SAFRAN), provided expertise but could not fully bridge the thrust deficit.

Delinking from TEJAS in 2008 was a pragmatic decision. The Indian Air Force proceeded with GE engines, allowing TEJAS MK-1 and MK-1A to enter service. Meanwhile, Kaveri underwent sea-level and high-altitude trials, achieving 72 kN wet thrust by 2024—a marked improvement from sub-50 kN in prior iterations.

Repurposing for UCAVs is ingenious. Platforms like the DRDO Ghatak, a stealthy flying-wing UCAV, require reliable dry thrust around 70-75 kN without afterburners, aligning perfectly with Kaveri's capabilities. This avoids the need for costly redesigns and accelerates deployment.

India's AMCA program hinges on this dual-track approach. The GE F414-INS6, licensed via Hindustan Aeronautics Limited (HAL), offers 98 kN thrust with afterburner—ideal for the stealth fighter's supercruise needs. Indigenous engines, potentially Manik or a Kaveri successor, will equip later blocks post-2035.

Global benchmarks validate Kamat's timeline. The US F135 engine for the F-35 took over a decade from concept to certification. Europe's EJ200 for the Eurofighter faced similar hurdles. India's compressed schedule, aided by private sector involvement like Godrej and TATA, signals maturity.

Private industry's role is expanding under Atmanirbhar Bharat. Firms such as Bharat Forge and Larsen & Toubro are scaling up for engine components, reducing import reliance from 70% to under 20% in coming years. This ecosystem will sustain long-term programs.

Self-reliance in engines counters supply chain vulnerabilities exposed by Russia-Ukraine tensions. Nations like China have surged ahead with WS-10 and WS-15 engines, powering J-20 stealth fighters, how these Chinese engine's claimed efficacy have not been validated by data or independent technical teams. Nevertheless, India must match this to secure its strategic edge in the Indo-Pacific.

Kamat's remarks, delivered amid ongoing CCS deliberations, inject optimism. With ₹10,000 crore earmarked for the next engine cycle, DRDO targets 110 kN class turbofans. Success here could cascade to naval AMCA variants and future sixth-generation designs.

Unmanned systems represent a low-risk proving ground. The Kaveri derivative's integration with UCAVs will yield flight data, refining designs for manned use. This iterative approach minimises risks in high-stakes fighter programs.

Broader deep-tech integration promises transformative gains. Quantum sensors could enhance engine health monitoring; AI-driven prognostics might predict failures pre-emptively. Advanced composites, like ceramic matrix ones, will enable higher turbine temperatures for efficiency gains.

India's defence innovation corridor—from Bangalore's aerospace hub to Hyderabad's avionics clusters—fuels this momentum. Institutions like IITs and IISc contribute via joint projects, blending academia with industry.

The Kaveri saga exemplifies resilience. From TEJAS de-linkage to UCAV enabler, it paves the way for aero-engine supremacy. By 2035, India could field a fully indigenous fifth-gen fleet, bolstering its great power ambitions.

Agencies