Tech Stack Behind India’s S-400 Air Defence Missile System: 5 Things to Know

The S-400 air defence missile system emerged as a critical asset for India on Wednesday, as the Indian Air Force reportedly used the Russian artillery system to intercept and take down targets moving towards the country. As per a report by NDTV, it was used to negate 15 missiles fired by Pakistan at Indian cities late at night and in the early hours of May 8. Also known as the S-400 Sudarshan Chakra system (Indianised name), the aerial threat-countering weapon features an advanced tech stack that has played an important role in many wars and general defence strategies.

S-400 Missile System: A Brief Overview

Originally named S-400 Triumf, its development was green-lit by the Soviet government in August 1991. However, it was put in limbo after the Soviet government collapsed soon after. In 1993, the Russian Air Force ordered a restart of its development, and in 1999, successful tests were conducted. After several deployment setbacks, it was finally approved in 2007 to service the 40N6 long-range missile.

According to The Defence Post, India signed a $5.43 billion (roughly Rs. 46,419 crore) deal to purchase five S-400 Triumf air defence systems from Russia. The first system was delivered in 2021, and two more arrived in the next two consecutive years. Two more systems are expected to be delivered soon. At present, all three S-400 missile systems are in operation.

Five Things to Know About the S-400 Sudarshan Chakra System

What is the S-400 missile system: The S-400 Triumf is a long-range surface-to-air missile (SAM) system. Regarded as one of the most sophisticated air defence systems in the world, it can detect, track, and intercept a wide range of aerial threats, including aircrafts, drones, cruise missiles, ballistic missiles, and even some stealth aircraft.

Specifications of the S-400: The aerial defence system can detect and neutralise aerodynamic targets at a maximum distance of 400kms, travelling at a maximum speed of 17,000 kmph or 4.8kmps. When fully deployed, it can engage 36 targets simultaneously by launching 72 guided missiles (two per target). The highly mobile system can move on roads at 60kmph and off-road at 25kmph.

Components of the S-400: The missile system comprises three components — missile launchers, a radar system, and a command centre. The launcher is a mobile, vertically-launching platform that can carry and fire a variety of missiles, according to Defence Research and Studies report. It works with both towed launchers and self-propelled launchers. The latter can be mounted on an 8x8 wheeled chassis. A full battalion can contain 12 launchers that can fire 48 missiles at once.

Each launcher has four canisterised launch tubes. The tubes are cold-launched vertically and the missiles are ejected by a gas generator before main engine ignition to reduce platform stress and radar signature. A launcher can relocate and redeploy within 5 minutes.

Coming to radars, the system uses a multi-layered radar architecture where each unit specialises in a different function, including surveillance, target detection, tracking, and fire control, as per the Editverse report.

The command centre of the S-400 Triumf system is known as the 55K6E Command Post, and it serves as the brain of the entire battalion. It manages radar data, prioritises threats, issues engagement orders, and coordinates multiple launcher vehicles and radar assets in real-time. It is mounted on a Ural-532301 6x6 high-mobility chassis. Notably, the command centre is fully automated and digital, with built-in redundancy and jam-resistant communications.

S-400 Missile Compatibility: The missile system is built with a multi-missile architecture that can accommodate targets at different ranges and altitudes. Each canister is tailored for specific engagement types, from high-speed ballistics to low-flying cruise missiles and stealth aircraft.

According to a Bulgarian Military report, some of the missiles that can be equipped on the Sudarshan Chakra system are as follows.

• 40N6 or 40N6E ultra-long-range interceptor with a range of up to 400km and a maximum altitude of 185km.
• 48N6DM long-range missile with a range of up to 250km and a maximum altitude of 30km.
• 9M96E2 medium-range precision interceptor with a range of up to 120km and a maximum altitude of 30km.
• 9M96E short-range high-agility missile with a range of up to 40km and a maximum altitude of 20km.

S-400 Guiding and Tracking System: With its comprehensive radar system, the S-400 is capable of tracking different types of aerial threats. The 91N6E Big Bird radar, which works on the L-band, can detect threats up to 600km in distance. Another, 96L6E, on the S-band, is tasked with altitude finding and low-altitude tracking. Plus, an option VHF-band radar can also detect stealth aircraft.

These radars also do the initial guiding of the missiles when locating the target. However, the main guidance system is stored within the command centre. With an inertial navigation system, it uses internal gyroscopes to guide the missile. Then, the radar system sends corrections to the missile mid-flight so it can adjust for any unexpected movements of the target.