Uttam is an indigenous multi-mode active electronically scanned array (AESA) fire-control radar developed by the Electronics and Radar Development Establishment (LRDE), a laboratory of India’s Defence Research and Development Organisation (DRDO). Designed primarily to replace the mechanically-scanned and Israeli EL/M-2032/EL/M-2052 radars on Indian fighter aircraft, Uttam is the first indigenously designed and built fighter-grade AESA radar to be cleared for series production in India, and is slated to become the standard-fit radar on later production batches of the HAL Tejas Mk1A from the 41st airframe onward.[1][2]
The Uttam programme originated from a DRDO decision in the mid-2000s to build indigenous AESA radar capability rather than remain dependent on imported fire-control radars for the Tejas Light Combat Aircraft and future IAF fighters. Formal project sanction and design work are dated to around 2008, with detailed development beginning in 2012 under LRDE, Bengaluru, working alongside DRDO’s Defence Avionics Research Establishment (DARE) and industry partners including Bharat Electronics Limited (BEL) and Astra Microwave Products.[3]
A full-scale engineering model of the radar was publicly displayed at Aero India 2017, and a fully functional flying prototype was demonstrated at Aero India 2019. Airborne trials began on modified testbed aircraft — including a Tejas Limited Series Production (LSP) airframe and a specially instrumented HAL HS-748 flying testbed — through the early 2020s, progressively validating air-to-air, air-to-ground, weather and terrain-avoidance/terrain-following modes.[3][4]
On 26 August 2022, DRDO formally handed over Transfer of Technology (ToT) for Uttam’s production to Hindustan Aeronautics Limited (HAL), clearing the path for series manufacture. The radar received a series of CEMILAC (Centre for Military Airworthiness and Certification) clearances through 2023–2025 covering hardware qualification and flight-trial milestones, and in April 2026 completed an extensive round of flight testing on the Tejas LSP-2 and LSP-3 prototypes that validated key performance parameters ahead of full operational clearance.[1][5]
Because Uttam’s certification and production ramp-up trailed the Tejas Mk1A production schedule, the Indian Air Force and HAL took the pragmatic decision to fit the first batches of Mk1A aircraft with the combat-proven Israeli IAI EL/M-2052 AESA radar, avoiding further delivery delays to a squadron force that was already critically short of fighter numbers. This was consistently described by DRDO and HAL officials as a sequencing decision rather than a rejection of Uttam; the programme has always intended for Uttam to become the standard-fit radar once cleared, beginning around the 41st Mk1A airframe.[2][6]
Uttam is a solid-state, liquid-cooled, X-band AESA radar built around distributed transmit/receive modules (TRMs), each an independent solid-state transceiver that allows the radar to electronically steer its beam without any moving parts — improving reliability, enabling multiple simultaneous beams/functions, and giving the radar a very low probability of intercept (LPI) against enemy radar-warning receivers.[3]
The baseline Uttam Mk1, developed for the Tejas Mk1A, uses gallium arsenide (GaAs) semiconductor technology in its TRMs and carries approximately 912 TRMs arranged in a modular, quad-band-stackable array. A second-generation Uttam Mk2, intended for the Tejas Mk2 (Medium Weight Fighter), moves to gallium nitride (GaN) TRM technology — offering higher power output, better thermal efficiency and reportedly upward of 900+ TRMs with a claimed detection-range improvement of roughly 25% over the GaAs-based design, alongside a repositionable “swashplate” antenna mechanism said to extend the radar’s field of regard beyond 100 degrees for improved off-boresight and dogfight-mode tracking.[7][8]
Reported operating modes include air-to-air search and track-while-scan, multi-target engagement support for beyond-visual-range missiles such as Astra, air-to-ground mapping (real and synthetic-aperture modes), ground-moving-target indication, sea-surface search, weather detection, and terrain-avoidance/terrain-following for low-level flight.[3]
DRDO and IAF-linked disclosures from 2025–2026 trial rounds indicate a tracking range of approximately 140 km against a fighter-sized (roughly 3–5 sq. m radar cross-section) aerial target in both air-to-air and air-to-ground modes, with detection ranges cited as exceeding 150 km under favourable conditions. DRDO officials have stated that in comparative trials Uttam matched or outperformed some established foreign competitor radars in detection range and simultaneous multi-target tracking capability, though independent third-party verification of these claims is limited.[1][9]
The Uttam architecture has spawned a family of derivative radars for other IAF platforms rather than remaining a single Tejas-specific product:
Virupaksha — A larger, higher-power GaN-based derivative sized for the Su-30MKI’s bigger nose radome, reportedly featuring around 2,400 TRMs. It is the radar selected to replace the Su-30MKI’s Russian-origin mechanically-scanned N011M Bars radar under a Sukhoi fleet upgrade programme valued at roughly ₹65,000 crore, covering an initial batch of 84 aircraft with flight trials on modified airframes beginning around 2026.[10][11]
Mirage 2000 and Jaguar upgrade proposals — Industry and IAF commentary has floated adapting a scaled Uttam-derivative radar for the ageing Mirage 2000 and SEPECAT Jaguar fleets as part of broader indigenous life-extension upgrades, though as of mid-2026 these remain proposed rather than funded, contracted programmes.[12]
Following the August 2022 ToT transfer, HAL is the primary production agency for Uttam, manufacturing it at its Hyderabad avionics facilities alongside continued LRDE design authority and quality oversight. BEL and private-sector electronics manufacturers are involved in TRM and sub-assembly production, part of the wider push to build a domestic AESA/GaN supply chain that also feeds programmes such as Virupaksha and future AMCA radar requirements.[5]
Uttam’s success is viewed within India’s defence establishment as a bellwether for indigenous high-end sensor design more broadly: AESA radar design demands mastery of high-frequency semiconductor fabrication, complex beamforming software, and thermal engineering that few countries possess indigenously. A mature, exportable Uttam/Virupaksha radar family would reduce India’s reliance on Israeli, French, and Russian radar suppliers across its fighter fleet and open a potential export line for allied air forces flying Russian- or Western-origin airframes.[9]
| Type | Multi-mode X-band active electronically scanned array (AESA) fire-control radar |
| Developer | Electronics and Radar Development Establishment (LRDE), DRDO |
| Production agency | Hindustan Aeronautics Limited (HAL), under ToT from DRDO (since Aug 2022) |
| TRM technology | Gallium Arsenide (GaAs) — Mk1; Gallium Nitride (GaN) — Mk2 |
| Number of T/R modules | ~912 (Mk1) |
| Cooling | Liquid-cooled |
| Tracking range (fighter-sized target) | ~140 km (air-to-air and air-to-ground modes, per 2025–2026 trial data) |
| Detection range | 150+ km (favourable conditions, claimed) |
| Modes | Air-to-air search/track, TWS, multi-target BVR engagement support, air-to-ground mapping (real beam/SAR), ground moving target indication, sea search, weather, terrain avoidance/following |
| Platform(s) | HAL Tejas Mk1A (from ~41st airframe), planned for Tejas Mk2 (Uttam Mk2); derivative Virupaksha for Su-30MKI |
| Predecessor/interim radar | IAI EL/M-2052 (fitted to early Tejas Mk1A production batches) |
| Status (mid-2026) | Flight-test and certification milestones completed; approaching series production fit on Mk1A |