Why doesn't India yet produce its own AESA fighter radar at scale?

Only eight nations can build the radar that lets a fighter jet see. India joined that list, but its newest fighters are flying with an Israeli set — and closing that gap is the story of the next few years.

The eye of a modern fighter

The active electronically scanned array, or AESA, is the primary sensor of a modern combat aircraft. Instead of one mechanically swept dish, it uses a fixed array of hundreds of tiny transmit/receive modules, each steering the beam electronically at speeds no motor can match. That is what allows a fighter to track many targets at once while jamming, mapping ground, and guiding beyond-visual-range missiles — the core of contemporary air combat.

Building one is hard because it is not one technology but several stacked on top of each other. The array is only as good as its individual modules, and behind them sits the signal processing that must form beams, track targets, and manage modes in real time. Then the whole assembly must survive the vibration, heat, and altitude of a fighter airframe and earn a military airworthiness certificate before it can fly on an operational jet. Few countries hold all these capabilities together.

Where India stands

India's answer is Uttam, a gallium-arsenide AESA fire-control radar developed by DRDO's Electronics and Radar Development Establishment (LRDE) since 2012, intended for the Tejas Mk1A, Mk2, the AMCA and the naval TEDBF.

Its test record is substantial. As of April 2024 the radar had completed 125 test sorties on Tejas Mk1 prototypes, clearing both air-to-air and air-to-ground modes, with performance reported on par with the Israeli EL/M-2052 it is meant to replace. Trials on Tejas prototypes and a Hawker 800 testbed reached a fighter-sized target track; DRDO says Uttam outperforms the EL/M-2052 in detection range and can track over 100 targets against 64. Technology transfer to Hindustan Aeronautics Limited (HAL) was completed in July 2023, and in April 2025 CEMILAC — India's military airworthiness certifier — confirmed that four stages of flight testing were done and the hardware qualified, recommending that subsystem production begin. The radar has also been approved for export.

Yet the first 83 Tejas Mk1A jets fly with the imported EL/M-2052. Uttam is deferred to the second batch of 97 aircraft. First production units are slated for delivery from 2026, with full operational deployment on the Mk1A expected around 2027. Most of the legacy fleet — the Su-30MKI, the Rafale — carries imported systems too.

Why the gap persists

The gap is not one of design; the design is demonstrated. It is one of the distance between a validated prototype and a serial-production line running at fleet scale. Serial integration on the first Mk1A batch was deferred specifically to avoid delaying jets already contracted, so a proven radar waits while an imported one ships.

Beneath that lies the deeper dependency. The active array is built from transmit/receive modules, and India's capacity to manufacture these at volume — in gallium arsenide, and increasingly in the higher-performance gallium nitride now under development — remains an emerging capability. A radar you can build in a lab in ones and twos is not yet a radar you can build in hundreds a year.

The path is already marked. Standing up module production at scale with HAL and a chosen production partner, completing the GaN work for improved range, and integrating from the second Mk1A batch onward would convert a demonstrated capability into a self-sufficient one. The design has been earned; what remains is the industrial climb from prototype to production line.