Why has no Indian-designed jet engine ever won full airworthiness certification?

Every manned fighter in Indian Air Force service — Tejas Mk1 and Mk1A, Su-30MKI, Rafale, Mirage 2000, MiG-29, Jaguar — flies on an imported or foreign-licensed engine. As of 2025, no indigenously designed engine has reached production certification. The powerplant remains the single most import-dependent subsystem in any Indian combat aircraft.

This is not for lack of a certification system. India has a working military airworthiness authority in CEMILAC, the Centre for Military Airworthiness and Certification. Its process is real and operating at scale: it has type-certified full aircraft like Tejas and the ALH, and thousands of indigenous items. CEMILAC follows a "concurrent certification" model, where certification runs alongside design and development, with documentation reviewed at successive stage-gates rather than only at the end. Design certification sits with CEMILAC; quality assurance during manufacture is handled separately by DGAQA. The end product is a Type Certificate granting authority to produce under government supervision.

The certification route works. What has never completed it is a wholly indigenous high-thrust turbofan.

Certifying an engine is genuinely among the hardest things an aerospace industry does. The hot-section blades must survive certification-level thermal and fatigue testing; that demands single-crystal superalloy turbine blades, a capability India is still building. The engine's digital control system — FADEC — must itself be flight-certified before the engine can be. And proving performance across the full flight envelope requires certification-grade altitude and thermal simulation. India lacks a domestic high-altitude engine test facility. The managing director of one private defence engineering firm has stated publicly that Indian industry has the technological and manufacturing capability to attempt a fighter engine, but identified exactly this — the absence of adequate domestic high-altitude testing — as the critical remaining gap.

The material foundations are, notably, further along than the engine. MIDHANI has received CEMILAC clearance for eight grades of superalloys, two of titanium alloys and four of special steels for aero-engine use, with over 200 parts type-certified and supplied for series production. In January 2024 it received provisional clearance for indigenous superalloys used in the AL-31FP components powering the Su-30MKI. Certification is succeeding at the materials level even where full-engine certification has not.

The lead programme is GTRE's Kaveri Derivative Engine. As of 2025-26 it has undergone over 140 cumulative hours of testing — 70 hours of ground runs at GTRE Bengaluru and 75 hours aloft at Russia's Baranov CIAM, followed by Il-76 flying-testbed trials. India relies on that Russian facility precisely because it has no domestic altitude test bed. In September 2025, Godrej Aerospace delivered the first serial-production Dry Kaveri unit, D1, to GTRE. That same month, GTRE partnered with HAL to integrate the afterburner-equipped engine onto a Tejas LSP airframe for manned flight testing. In December 2025 the Ministry of Defence mandated a 2026 certification target for the Dry Kaveri, tied to Cabinet Committee on Security clearance for the Ghatak UCAV.

Even certified, the Kaveri is initially intended for the unmanned Ghatak and derivative applications. For the AMCA fifth-generation fighter, the government is negotiating with the US to produce the GE F-414 in India with more than 80 per cent transfer of technology for the first phase, AMCA Mk-1; a wholly indigenous high-thrust engine is reserved for the later Mk-2.

The gap persists structurally: the certifying institution exists, and the material inputs are maturing, but the engine hardware, hot-section materials, FADEC and — critically — the domestic test infrastructure have not all reached certifiable maturity at once. In February 2026, the Defence Minister set a 5–7 year deadline at GTRE for an indigenous fighter engine, noting that prior decades had not delivered results. Closing the gap means completing the physical foundations beneath the certificate, not the certificate itself.