Kusha: DRDO's indigenous rival to S-400

Highlighting the system’s success, Group Captain D K Pandey (retired), senior fellow at the Centre for Aerospace Power and Strategic Studies, observed that the operation underscored defence in depth, which is achieved by overlapping layers of detection, engagement, and interception ensuring that if an adversary penetrates one layer, others remain to counter it.

This underpins Project Kusha, the Defence Research and Development Organisation’s extended-range air defence programme under development and intended to rival the S-400. A defence source said Kusha’s three missiles — with interception ranges of 150 kilometres (km) for the M1, 250 km for the M2, and 350 km for the M3 — will occupy the tier between the MRSAM (70 km) and the S-400 (120, 200, 250, and 380 km using four interceptors). “It is designed for seamless integration with the IACCS,” the source added.

India procured the S-400 from Russia in a 2018 deal worth about ~40,300 crore. Although all five squadrons were scheduled for delivery by end-2023, two remain and will reportedly arrive in 2026 and 2027. With five Kusha squadrons slated for the IAF at a reported cost of ~21,700 crore, the outlay is about half that of the Russian system.

Pandey also noted the technological complexity: not only designing interceptors for fighter jets, cruise missiles, drones, and precision-guided munitions, but also tracking this wide threat spectrum within one system. “Detecting such a variety of objects across different ranges using a single type of sensor is difficult due to limitations rooted in physics,” he said. The Army, for example, used radars calibrated for small drones to counter Pakistani attacks in May.

Pandey highlighted that Kusha’s sensors — active electronically scanned array radars using thousands of transmit–receive modules to steer beams electronically at near-instant speeds, making them faster, more precise, and harder to jam than mechanical radars — will ensure 24/7, all-weather capability.

Operation Sindoor marked the advent of large-scale kinetic, non-contact warfare in the subcontinent: campaigns fought without direct troop engagement, relying instead on long-range aerial strikes. Although the S-400 proved its worth, Pandey argued that Pakistan’s inevitable standoff capability upgrades make it vital to assess whether more units can be procured at acceptable cost, and whether Russia — still engaged in Ukraine — can deliver them on time. “Beyond cost efficiency and sovereign control, Kusha is also being designed to suit India’s diverse geography and weather conditions.” This aligns with Mission Sudarshan Chakra, which aims to safeguard every critical site, strategic and civilian, by 2035. Kusha is widely regarded as a potential component.

The first test of Kusha’s M1 missile is reportedly slated for 2026, with the other two to follow within two years. Development is targeted for completion by 2028, with induction expected from 2030 onwards.

According to Pandey, Kusha’s operational role is likely to sit a tier below the two-phase ballistic missile defence programme, though with some overlap at the terminal interception stage.