India has bolstered its air defence capabilities with the arrival of the fourth squadron of the S-400 Sudarshan air defence system from Russia. This shipment is part of a larger contract signed in 2018, which includes the acquisition of five squadrons, three of which were delivered two years ago. The arrival of the fourth squadron comes after delays attributed to the ongoing Russia-Ukraine conflict. The S-400 system has proven effective in past operations, notably during Operation Sindoor, where it successfully engaged a high-value Pakistan Air Force surveillance aircraft at a distance exceeding 300 km. Looking ahead, the fifth squadron is anticipated to reach India within the next few months. Additionally, the Defence Acquisition Council has approved plans for five more S-400 squadrons, indicating India's commitment to enhancing its air defence capabilities. Alongside these acquisitions, India is also pursuing indigenous development of air defence systems under Project Kusha, aiming to create systems capable of neutralizing enemy drones at comparable ranges to the S-400.