Several alternative engines are considered or proposed to replace General Electric's F404-IN20 engine for the Indian TEJAS jets, primarily aiming at enhanced performance, strategic self-reliance, and long-term supply security.

The primary alternative engines considered to replace GE's F404-IN20 for the TEJAS MK-1A fighter jet are:

Snecma M88-4E

Derived from the M88-2 engine that powers the Rafale fighter. Produces thrust around 75 kN, with development tests reporting up to 90 kN. Advantages include a better thrust-to-weight ratio, smaller size, lower infrared signature, and superior fuel efficiency.

Commonality with the IAF's Rafale fleet is a key operational benefit. Would require some airframe redesign and certification, achievable within about three years.

Eurojet EJ200

Engine for the Eurofighter Typhoon with a wet thrust of approximately 90 kN. Known for advanced technology, light weight (~990 kg), modular design, and excellent thrust-to-weight ratio (9.17:1). Provides enhanced maneuverability and easier maintenance. Considered a strong contender due to its performance and ease of integration.

Also demands fuselage and intake redesign and flight testing for certification.

Russian Klimov RD-33MK (Contentious Option)

Afterburning thrust near 89 kN, higher than F404-IN20's 84 kN. Has a longer service life but heavier weight and lower bypass ratio. Designed for high-performance aircraft like MiG-29K and MiG-35. Integration challenges due to size, weight, and system differences. Less fuel efficient compared to F404-IN20, though FADEC inclusion in latest versions improves performance.

Strategic considerations around sourcing and geopolitical constraints lessen its attractiveness.

Indigenous Kaveri Engine Derivatives

The Gas Turbine Research Establishment (GTRE) developed the indigenous Kaveri turbofan engine since the 1980s as a power-plant for TEJAS.

Although initial Kaveri versions faced developmental issues, recent efforts focus on reviving and upgrading it with a target wet thrust of around 90 kN, surpassing the F404's 84-85 kN thrust.

This would push it closer to the GE F414 engine class, potentially powering the TEJAS MK-1A and future variants while reducing reliance on costly foreign engines. However, the Kaveri engine is still under development and not yet certified for operational use.

GTRE's Kaveri Engine Derivative (KDE) aims for around 73-74 kN thrust with afterburner. Built on Kaveri's matured core technologies supported by experience from Safran consultancy. Targeted for demonstration and potential deployment in TEJAS MK-1A eventually.

Offers the promise of complete strategic autonomy if matured successfully but requires further development and testing.

Among these, Snecma M88-4E and Eurojet EJ200 are the most practical near-term alternatives to replace or supplement the F404-IN20 engines because of their maturity, performance, and compatibility potential with TEJAS’s requirements. The Kaveri derivative represents a long-term sovereign solution. The RD-33MK, while powerful, is less favoured due to integration complexity and strategic considerations.

IDN (With Agency Inputs)