Digital avionics architecture and computing

Between 90 and 95 per cent of the semiconductors inside Indian defence avionics systems are imported. The digital brain of every modern Indian aircraft runs, at its lowest level, on silicon made elsewhere.

Digital avionics is the nervous system of an aircraft: the mission computers that fuse radar, electronic warfare and navigation data; the flight control computers that hold an unstable fighter in the air through deterministic, redundant computing. Modern architectures build this as integrated modular avionics — shared computing partitioned by standards such as ARINC 653, DO-178C and DO-254. Only five nations field this capability at full stack: the United States, France, Israel, Sweden and China. It is hard because it demands ruggedised, radiation-tolerant hardware, deterministic real-time software, and certification chains that must prove an aircraft will not fail.

India has crossed from paper to fielded systems. The Aeronautical Development Agency designed the quadruplex fly-by-wire Digital Flight Control Computer and open-architecture mission computer for Tejas; the Mk2 adds an auxiliary computer for triple-layer redundancy. HAL and DRDO jointly developed the Mk2 mission computer to integrate sensor fusion, weapon control and navigation without foreign dependencies. Bharat Electronics holds a ₹2,400 crore contract (2023–2028) to supply twenty types of critical avionics for Tejas Mk1A. DRDO's Centre for Airborne Systems built the complete indigenous mission suite for the NETRA AEW&C, which reached Final Operational Clearance with three aircraft delivered on the EMB-145 platform. Data Patterns is developing the unified display system for Tejas Mk2; Research Centre Imarat has achieved laboratory-scale quantum accelerometers and magnetometers more sensitive than the ring-laser gyroscopes used in Tejas and Rafale.

Yet the status remains emerging. The integration works at subsystem level; no indigenous full-stack modular avionics architecture has been fielded, and the core computing hardware is imported.

The gap persists at the foundation. India possesses no indigenous aerospace-grade semiconductor manufacturing and no domestic high-reliability computing hardware — the ruggedised, radiation-hardened processors avionics require come from the US and Europe. More than 90 per cent of chip-making equipment and 85 to 90 per cent of specialty chemicals and electronic-grade gases are sourced abroad. The IMA standards themselves, and the licensed software tools for model-based design and formal verification, remain outside independent Indian capability. DGCA and CEMILAC certify domestically but reference FAA and EASA standards.

Closing this would mean building beneath the working layer: defence-spec silicon, an indigenous real-time operating system, and qualified development tools. The quantum sensors show the laboratory can lead; ruggedisation for combat is the unsolved step. The ecosystem is present but fragmented — R&D, test infrastructure and certified suppliers not yet joined into an end-to-end chain.