India’s purported intention to test the domestic Kaveri engine on the Sukhoi Su-30MKI shows both aspiration and a desperate attempt to bridge the long-standing gap in the development of a domestic fighter jet engine that is sustainable, dependable, and adaptable.
Originally intended to power the Light Combat Aircraft (LCA) TEJAS, the Kaveri program was started in the 1980s. However, due to ongoing thrust and reliability issues, it was repurposed mostly for the Ghatak UAV.
Republic World claims that the current project is modeled by the US F-22 development effort, whose experimental engines underwent lengthy validation prior to combat integration, albeit under extremely different logistical and technological circumstances.
The Su-30MKI’s twin-engine powerplant, the Saturn AL-31FP, generates 88–90 kN of dry thrust, but the Kaveri GTX-35VS only produces 49–51 kN. Performance and structural limitations are a result of this mismatch.
As opposed to heavyweight platforms like the Su-30MKI, the Kaveri’s thrust class is more akin to the General Electric F404 engine found in early TEJAS fighters. If integration is attempted on the latter, flight safety and maneuvering envelope could be seriously jeopardized.
It may seem counterintuitive to test an underpowered engine on such a huge and heavy airframe, but the Su-30MKI offers a reliable and accessible test bed. Asymmetric power testing is made possible by the airframe’s surplus thrust from a single operational AL-31FP, which serves as a safety net in case the developing Kaveri malfunctions in midair.
The Su-30’s twin-engine design lowers the operational risk of catastrophic failure during airborne tests, in contrast to TEJAS, which only has one engine. This makes it a more useful platform, even though it is technically mismatched.
Pratt & Whitney’s F119 engine was not first put to the test on the F-22 Raptor during its development. Prior to high-performance testing, engineers were able to assess the engine in a controlled setting using a specially modified Boeing 747SP as a flying test bed.
India depends on its current military fighters for integration trials because it lacks such sizable dedicated test aircraft. This key distinction draws attention to the technological limitations that India’s program faces.
This decision comes with a number of challenges. The Su-30’s mounts, ducting, and control systems will need to be modified for integration in order to accommodate a totally new engine shape and performance profile.
Digital-analogue interfaces and electronic engine controls need to be completely redesigned. Additionally, stress testing will be required to verify that the Kaveri’s temperature, vibration, and airflow parameters are compatible with those of the Su-30. The engine cannot operationally replace the AL-31FP due to the thrust deficit, even if safe integration is accomplished.
India’s intention to carry out this test has political significance as well. Due to ongoing problems with maintenance and replacement parts brought on by Russian sanctions, New Delhi is speeding up the search for a domestic substitute. Despite its lack of power, the Kaveri is a valuable learning tool for GTRE and HAL to comprehend flying performance outside of lab simulations. Even failure would provide useful information about high-altitude handling, material tolerances, and combustion stability.
Experts contend that adapting the TEJAS or a smaller domestic test bed more closely resembles the Kaveri’s planned thrust class, even if GTRE’s reasoning for employing the Su-30MKI focuses on safety through dual engines.
Because of its increased aerodynamic loads and design requirements, the Su-30 may speed up learning, but it also introduces needless complication. It would be more sustainable in the long run to build or lease a specialized flying test bed, much like the French or American methods.
The Kaveri will not be fit for operational fighter deployment based on the projected flying testing, especially not on heavier platforms like the Su-30MKI.
Nonetheless, they represent a significant experimental phase in India’s gradual transition to jet engine independence. Even a little amount of success, with proper management, will directly support derivative projects like the Ghatak engine for unmanned systems and the Kaveri-Snecma co-development for AMCA. Although there are still significant hazards, India may be able to break through a decades-long technological barrier with the help of the insights gathered from actual aerial testing.
