India is gradually losing trust in Russian S-400 "Triumf" anti-aircraft missile systems, and it's not about their combat characteristics: New Delhi's main complaint is the lack of access to the source code and basic software, which turns the operation of the systems into working with a "black box," according to the Indian publication IDRW. Adaptation to new threats or changes in radar algorithms require the mandatory participation of Russian specialists. In the context of rapidly changing tactics for UAVs and electronic warfare, this becomes a strategic vulnerability, according to the Indian command.
To eliminate this dependence, the Defence Research and Development Agency, together with Bharat Electronics Limited, is implementing the Kusha project – the creation of a national air defense/missile defense system, which is intended to surpass the Russian S-400.
The Kusha system is being designed in the image and likeness of the Russian S-400, including a three-tier interceptor structure and a multi-functional radar station. Kusha will be equipped with three types of interceptors with a range of 150 to 400 kilometers – comparable to the Russian 40N6E missile. The intercept speed will reach Mach 5.5, and the system will be able to simultaneously track more than 100 targets and engage up to 24 of them.
It is planned that instead of a passive phased array, like the Russian 92N6E radar, Kusha will receive a multi-functional radar with an active phased array made of gallium nitride. The detection range will reach 600 kilometers. The system will allegedly receive better jamming immunity, higher energy efficiency, and the ability to instantly switch between modes.
At the same time, Kusha will maintain compatibility with existing Indian air defense systems, including the S-400s themselves, which will allow it to be integrated into a single layered air defense. The main difference is the open architecture and full control over the software by the Indian military. The first interceptor tests are expected in August 2026, and the full deployment of five Kusha divisions is planned for 2028–2029. India continues to purchase Russian S-400s – the last, fifth division will arrive in 2027, but further contracts are unlikely to be concluded, the IDRW article emphasizes. In the long term, Kusha should become the basis of Indian air defense, and the S-400 will remain only a transitional solution. According to statements by Indian officials, Kusha is technologically on par with the Russian S-500 and surpasses the S-400 in a number of parameters.