India had sought bids from General Electric Co. and Eurojet Turbo GMBH to supply two turbofan engines for the TEJAS, the country’s first light combat aircraft, after an almost two-decade effort to develop a local after-burning turbofan failed to deliver a sufficiently powerful engine. General Electric (GE) won the bid and has delivered two qualified GE-F414 engines to be tested on the planned home-grown TEJAS Mk-2 single engine fighter and is looking to collaborate with India to build engines for the proposed advanced medium-combat aircraft. The first two engines are for flight test. The engines are ready to go as and when the fighter is ready. GE has committed to deliver six more engines and the initial deal covered the purchase of 99 GE F414 engines

The tender stipulates transferring at least 60% of the engine technology to HAL to produce the engines locally, it was reported that GE is willing to give more than 50% of the technology.

The Aeronautical Development Agency, or ADA, the jet’s designer, is evaluating the General Electric’s GE-F414 for the Mark II version of TEJAS. The GE-F414 powers the carrier capable Boeing F-18 "Super Hornet" jets. GE, has a manufacturing facility in Pune and the company says it could meet the mandated 50% offset requirement of local production for defense contracts within India.

The delay in the indigenous engine availability is what has driven ADA to go for an alternative engine, TEJAS is a tailless single-engine supersonic fighter with delta wings—shaped like a triangle—which uses fly-by-wire technology that enables pilots to control the plane electronically through on-board computers.

The plane is undergoing development trials with a GE-F404 engine, but this falls short of the thrust it requires in operational conditions. The Indian Air Force (IAF) has so far placed orders with state-owned plane maker Hindustan Aeronautics Ltd (HAL) for 123 TEJAS fighters composing of 40 - Mk-1 plus 83 - Mk-1A aircraft. Four squadrons of LCA Mk-2 aircraft is planned to be acquired after completing production of LCA Mk-1.

India’s Gas Turbine and Research Establishment, or GTRE, a DRDO unit in Bangalore, has been working on the indigenous Kaveri engine for the TEJAS for nearly two decades but the Kaveri program failed to satisfy the necessary technical requirements or keep up with its envisaged timelines and was officially delinked from the TEJAS program in September 2008.

Modern turbofans incorporates clear-cut and exclusive technologies which is difficult to master such as a three-stage fan with a high pressure ratio, full-authority digital engine control (FADEC), multi-stage high-pressure (HP) compressor, combustor using advanced cooling and thermal protection, sophisticated High-Pressure/Low-Pressure turbines using ceramic matrix composites (which is exclusive to the GE-F414 engine) with powder metallurgy discs and single crystal blades (as opposed to dovetailed blades), reheat system (afterburner) and a convergent-divergent nozzle design.

A few companies such as GE, Snecma, Eurojet and Russia’s NPO Saturn make engines for fighter jets, but they seldom share the technology, which typically changes every two years.

The Kaveri engine got a leg up after a $2-million consultancy agreement was finalized with leading French defense manufacturer Safran to help revive the Kaveri project. The best part of the deal is apart from the initial consultancy fees, India may not need to spend on development as the French side has proposed to make the Kaveri flight-worthy within 18 months for integration into the TEJAS by 2020. 

India began building a home-grown engine for TEJAS after HF-Marut, the country’s first indigenously built supersonic jet, flopped in the 1960s because it could not get a suitable engine.

GTRE must continue developing an operable engine for our fighter planes but it has to play catch-up and master the technology on its own in the years to come by overcoming the aforementioned snags.

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