India has spent almost four decades trying to develop a fighter aircraft engine of its own. Yet every fighter jet currently operated by the Indian Air Force still depends on a powerplant developed abroad. The situation exposes one of the most difficult gaps in India’s defence-industrial ambitions, wrote Palak Gupta in an exhaustive analysis piece on CNBCTV18.
The country has made significant progress in aircraft design, missiles, radars, air-defence systems and unmanned platforms. However, it has not yet produced an indigenous fighter engine powerful and reliable enough to propel a frontline combat aircraft. The TEJAS, India’s home-grown light combat aircraft, flies with the GE F404 engine developed by General Electric in the United States.
The initial versions of India’s fifth-generation stealth fighter, now being designed under the Advanced Medium Combat Aircraft, or AMCA, project, are also expected to use a foreign engine. Both the TEJAS and AMCA are described as indigenous aircraft programs. Neither, however, currently has an indigenous fighter engine.
This dependence has remained one of the most persistent weaknesses in India’s pursuit of strategic autonomy.
The Kaveri Story
India’s effort to develop a domestic fighter engine began in 1986. The Defence Research and Development Organisation’s Gas Turbine Research Establishment, or GTRE, in Bangalore proposed the development of what later became known as the Kaveri engine. The Government of India formally sanctioned the project in March 1989. The initial sanctioned cost was approximately ₹383 crore. The engine was designed to generate roughly 85 kilonewtons of thrust.
That level of thrust was considered necessary to power a fighter aircraft such as the proposed Light Combat Aircraft, which eventually became the TEJAS. The Kaveri represented a major technological challenge for India. It involved the development of a complete military turbofan, including the fan, compressor, combustor, turbine, afterburner, control systems and high-temperature materials required for sustained operation. The engine’s core, along with its predecessor known as the Kabini, was sent to Russia for high-altitude testing. The testing was conducted in three spells beginning in August 1998.
The details were later disclosed in a written reply given in the Lok Sabha in 2005 by then Defence Minister Pranab Mukherjee. The tests revealed that the engine had not achieved the performance required by the TEJAS. Its thrust fell short of the aircraft’s requirements. The engine also faced problems linked to weight, reliability, materials and high-temperature performance. India subsequently selected the American-made GE F404 engine for the TEJAS.
By the late 2000s, after years of ground and high-altitude testing, the Kaveri had been separated from the TEJAS program as the aircraft’s indigenous engine option. The decision allowed the TEJAS project to move forward, but it also confirmed the seriousness of India’s fighter-engine challenge.
Where Kaveri Stands Today
The Kaveri engine has not been abandoned. Instead, the experience gained from the original project is being used for more specialised applications and redesigned derivatives. A non-afterburning version, known as the Kaveri Dry Engine, has reportedly demonstrated approximately 49 to 52 kilonewtons of thrust. That output is substantially below what is required for a conventional manned fighter. It could nevertheless be suitable for an unmanned combat aircraft.
One possible application is the Ghatak, India’s stealth unmanned combat air vehicle being developed by the DRDO. The dry engine does not require an afterburner. This reduces complexity and makes it more practical for an unmanned platform whose design requirements differ from those of a high-performance manned fighter. The engine could give the Kaveri project a meaningful operational role. It would also allow Indian engineers to gain additional experience in engine integration, flight testing, production and long-term maintenance.
The Kaveri derivative is reported to be aimed at producing approximately 50 kilonewtons of thrust. For fighter aircraft, the DRDO is also pursuing a redesigned higher-thrust version commonly referred to as Kaveri 2.0. This version is associated with a reported thrust target of around 90 kilonewtons.
Kaveri 2.0 is not simply an attempt to restart the original engine. The objective is to build on the knowledge obtained from the earlier Kaveri effort while incorporating new design approaches, improved materials and better manufacturing methods. The redesigned engine is intended to reflect the lessons learned from decades of testing and development. Even so, the more powerful engine required for the AMCA remains a separate and more demanding challenge.
The AMCA Engine Contest
India is examining foreign partnerships for the high-thrust engine needed by later versions of the AMCA. The aircraft’s initial prototypes are expected to use the GE F414 engine. The F414 is a more powerful engine than the F404 and is intended to support the early flight-testing and development stages of the AMCA. The long-term objective, however, is to equip later versions with a powerplant controlled and manufactured domestically. France’s Safran and India’s GTRE have proposed jointly developing a new fighter engine.
The proposed project has been reported to involve an estimated cost of approximately ₹61,000 crore. The partnership model is intended to go beyond the purchase of completed foreign engines. India wants a role in design, manufacturing, testing, intellectual property and the development of advanced technologies. The hot section is especially important. It includes the combustor, turbine and associated components that operate under extreme temperatures and pressures. UK’s Rolls-Royce has also emerged as a contender.
In August 2026, Rolls-Royce announced a strategic intent to work with Reliance Industries on an indigenous combat engine for the AMCA. The proposal involves cooperation in the design, development, manufacture and delivery of an Indian combat engine. Reports have indicated that the Rolls-Royce proposal includes extensive technology transfer and Indian intellectual property. If a contract were signed by the end of 2026, the proposed schedule could involve engine-core testing by 2030. The first flight of an aircraft powered by the new engine could potentially take place by 2034. Production could begin around 2036. These dates remain projected milestones rather than confirmed commitments.
Neither the Safran-GTRE proposal nor the Rolls-Royce-Reliance proposal has yet resulted in a signed development contract. The competition is significant because India is seeking access to fighter-engine technology that only a small number of countries have mastered. The United States, Russia, France, the United Kingdom and China (though not independently verified) are generally regarded as the only countries with demonstrated capabilities to design and manufacture modern fighter engines at scale.
The AMCA engine decision will therefore have consequences well beyond a single aircraft project. It could determine whether India becomes capable of independently designing, producing, upgrading and exporting advanced combat aircraft.
Why Fighter Engines Are Difficult
Fighter engines are difficult to develop because they must combine high thrust, low weight, compact dimensions, rapid acceleration and long-term reliability. They must operate safely across a wide range of speeds, altitudes and temperatures. The challenge is not limited to aerodynamic design. Materials science and manufacturing precision are equally important. A modern fighter engine can operate at temperatures exceeding the melting point of some of the metals used in its components. This is possible only through the use of advanced cooling systems, specialised alloys, ceramic coatings, precision manufacturing and tightly controlled production processes. The turbine blades are among the most technically demanding components.
They must withstand extreme temperatures, intense centrifugal forces, rapid rotational speeds and repeated thermal cycles. Their performance depends on advanced metallurgy, single-crystal or directionally solidified structures, internal cooling passages and protective coatings. India’s engineers have repeatedly identified the Kaveri’s hot section and related materials technologies as central obstacles. The engine’s ability to produce thrust was affected by difficulties in achieving the necessary turbine temperatures and pressure ratios.
The development of suitable blades, coatings and combustion technologies requires long-term experimentation. It also requires production facilities capable of maintaining extremely narrow tolerances. A design can succeed on paper and still fail during production if the industrial base cannot manufacture components consistently.
Engine development also depends on extensive testing. India historically lacked a domestic high-altitude testing facility capable of fully evaluating engines of this class. As a result, the Kaveri program relied on testing facilities and flying testbeds in Russia.
The proposed Safran-GTRE and Rolls-Royce-Reliance partnerships could provide another route towards a domestically controlled high-thrust engine. The outcome will depend on whether India secures genuine technology access rather than limited manufacturing participation. It will also depend on the ability of the government, public-sector organisations and private industry to maintain funding and technical continuity over several decades.
The propulsion gap is therefore doing more than exposing a weakness. It is changing how India approaches strategic technology development. The country is bringing private industry into major defence projects earlier. It is keeping competing foreign technology options open. It is attempting to establish manufacturing relationships before the engine itself enters service
India’s fighter-engine journey has not yet produced the desired frontline powerplant. But it has helped create an increasingly experienced domestic propulsion ecosystem. The next phase will determine whether that experience can be converted into a reliable, high-thrust engine for India’s future combat aircraft.
The success or failure of that effort could shape the country’s aerospace ambitions for decades.
Agencies
