India's KAVERI afterburning turbofan developed by GTRE a lab of DRDO

The Indian aerospace industry lacks an indigenous aero-engine to power its aircraft

by Group Captain A K Sachdeva (Retd)

The F-100 Super Sabre, the world’s first supersonic fighter jet, flew first in 1953, instigating the fledgling Indian Air Force (IAF) to formulate an Air Staff Requirement (ASR) for a supersonic combat aircraft of its own. The HF-24 Marut was designed in the 1950s as a supersonic (Mach 2.0) combat fighter capable of interception role. However, the final production aircraft barely achieved the speed of sound (Mach 1.0) and was limited to the ground attack role as it lacked the speed and agility to be an interceptor. The reason was that in the absence of a suitable indigenous engine, it was powered by a British Orpheus engine that was available as it was being licence-produced by HAL for the Gnat aircraft but did not have the power to meet the design requirements. The IAF was reluctant to accept the aircraft and only two-thirds of the planned numbers were built; indeed, as per one account, the HF-24 was technically obsolete by the time it was first delivered in 1964. As a significant collateral injury, the lack of an indigenous engine also rang the death knell of any future designs following up on the HF-24.

Six decades later, the Indian aerospace industry, which the Prime Minister and the Defence Minister visualise as a global hub in the future, still continues to suffer from the lack of an indigenous aero-engine to power its aircraft. Gas Turbine Research Establishment (GTRE), the public sector enterprise tasked to design and develop gas turbine engines for military applications, was formed in 1959 and has huge, sprawling real estate in a prime area of Bengaluru and employs nearly 1,000 personnel. However, its output has been depressing; in the 1960s, it failed to improve the Orpheus engine to up-power the HF-24 Marut, and since then, has shelved the original program to produce Kaveri, an engine for the TEJAS Light Combat Aircraft (LCA), which is consequently powered by a GE engine.

The indigenous Advanced Multi-role Combat Aircraft (AMCA), when it is ready to fly, also appears destined to fly with foreign engines. It is disappointing to note that while the TEJAS is a 4+ generation combat aircraft design and the AMCA a fifth generation one, both currently await an indigenous engine.

Engine technology has been a closely guarded intellectual property that foreign nations (for strategic reasons) and international Original Equipment Manufacturers (OEMs) (for business motives) guard zealously and are loath to part with. Since the 1960s, the IAF has operated leading-edge combat aircraft licence-manufactured by Hindustan Aeronautics Limited (HAL), but India has failed to acquire leading-edge engine technology.

So, in the absence of a shortcut to foreign technology, India was left to its own devices to design and develop engines for its needs. Unfortunately, the reliance laid by the government on the public sector since Independence patronised an incapable horde of industries (including HAL and GTRE), frayed by internal inefficiencies, and so the indigenous aero-engine industry remained stunted. The more capable private sector was left out of the reckoning. In recent years, the private sector has ventured into this niche segment but is looking at small engines, more suitable for Unmanned Aerial Vehicles (UAVs), and not for combat aircraft.

GTRE, despite all the money and resources, poured into it since 1959, is yet to overcome fundamental issues of metallurgy for turbine blades, integrated single-blade and disk technology, single-crystal blades, and thermal barrier coatings; it also lacks a high-altitude engine test facility, a flying test-bed and a wind tunnel to validate engines above 90 Kilo Newton (KN) thrust for the TEJAS and 110 KN engine for the AMCA.

Is foreign collaboration the way ahead? An interactive wargame conducted by Insighteon Consulting, a Delhi-based aerospace and defence consulting firm, in August 2022, reached the conclusion that co-development models will not result in a new design or enhanced capability as foreign OEMs are unlikely to give away their technology to entities in India, which represents a huge aero-engine market in the coming years.

Currently, India’s quest for 114 Multi-Role Fighter Aircraft (MRFA) to fill the combat squadron shortfall of the IAF, is a lucrative prospect, with eight OEMs in the fray. If India leverages its Atmanirbhar commitment and bargains hard for the deal in such a way that engine technology transfer is stipulated as part of the contract, our floundering aero-engine industry may yet take off.

Should that not work out, it is time for India to examine strategies to achieve a leading-edge aero-engine industrial base on its own -- critical not only to the Indian combat aircraft programs but also to India’s vision of acquiring global aerospace power status. Perhaps it is time for the Prime Minister’s Office (PMO) to take the aero-engine industry under its direct oversight, as was the case with India’s spectacularly successful space program.

Bureaucratic bungling has to be removed from the scene, GTRE’s internal incompetence has to be substituted by accountability, and the organic productivities of the private sector integrated into the campaign for a leading-edge aero-engine. The academia can be roped in for Research & Development (R&D), while public sector laboratories and test facilities can be made available to the private sector. India just cannot afford to let a feeble aero-engine segment become the Achilles’ Heel in its otherwise inexorable march towards self-reliance.

The writer is a former Senior Research Fellow of the Institute for Defence Studies and Analyses, New Delhi