India has received the fourth batch of the famous Russian-made S-400 air defence system. With this new arrival, India’s long-range air defence network has become much stronger and more capable of protecting its skies. The system reached India on schedule in May, and according to defence sources, it will soon be deployed in an active operational area where it is needed most.
This delivery is part of a big $5.43 billion deal (around ₹52,128 crore) that India and Russia signed back in 2018. Under this deal, India agreed to buy five S-400 regimental systems. What is interesting is that India went ahead with this purchase even though America repeatedly warned of possible sanctions under a law called CAATSA. This showed the world that New Delhi chose its own strategic freedom and national security over outside pressure.
Three S-400 squadrons are already guarding our borders, and now the fourth one has arrived after some delay caused by the ongoing Russia-Ukraine war. Officials have said the fifth and last squadron is expected to reach India by 2027, and the deliveries are now back on track.
A big upgrade is coming too. Senior officials revealed that the S-400 will soon get AI-based support systems. In simple words, artificial intelligence will help operators identify dangers faster and pick targets more smartly. When many threats appear on the screen at once, the AI will quickly suggest which enemy aircraft, missile, or drone is the most dangerous and should be tackled first. But remember, the final decision to fire will always rest with a human operator. The AI only advises; the human commands. This system can recognise different threats like ballistic missiles, fighter jets, drones, and cruise missiles, helping the S-400 use its interceptor missiles more wisely.
Three S-400 squadrons are already guarding our borders, and now the fourth one has arrived after some delay caused by the ongoing Russia-Ukraine war. Officials have said the fifth and last squadron is expected to reach India by 2027, and the deliveries are now back on track
The S-400 Triumf is counted among the most advanced long-range air defence systems in the world. It can detect and destroy aircraft, drones, cruise missiles, and ballistic missiles from very long distances. It forms an important layer of India’s multi-layered air defence, protecting both our western and northern borders. Officials also confirmed that the S-400 played an important role during Operation Sindoor, where it effectively handled aerial threats and proved its skill at spotting and engaging targets from far away.
Along with these Russian systems, India is also building its own air defence network under the larger ‘Sudarshan Chakra’ initiative. The S-400 works together with Indian-made systems like Project Kusha, Akash, and ballistic missile interceptors to create a strong protective shield over the country.
Now, let us understand how this powerful machine actually works. A complete S-400 system has six main parts. First, a launch vehicle that carries the missiles. Second, a command-and-control post mounted on a vehicle. Third, a long-range surveillance radar called the Big Bird. Fourth, the Grave Stone fire control radar. Fifth, an all-altitude radar. And sixth, a mobile mast system. The missiles are carried on sturdy trucks like the BAZ or MAZ series, and each launcher truck can hold up to four launch tubes. These tubes contain missiles of different ranges: the 9M96 covers 40 km, the 9M96 E2 covers 120 km, the 48N6 covers 250 km, and the powerful 40N6E reaches up to 400 km.
The S-400 Triumf is counted among the most advanced long-range air defence systems in the world. It can detect and destroy aircraft, drones, cruise missiles, and ballistic missiles from very long distances. It forms an important layer of India’s multi-layered air defence, protecting both our western and northern borders
The radars are the eyes of the system. The Big Bird (NATO name Tomb Stone) can detect aircraft, helicopters, missiles, and drones up to 600 km away, and can track 300 targets at the same time. The Grave Stone radar guides the missiles with a range of 400 km, while the 40V6MR helps catch low-flying targets trying to hide behind hills and terrain.
The working is simple to follow. The Big Bird radar first spots a target. It passes this information to the command-and-control post, which decides whether the target is a friend or an enemy. Once permission is given, the launchers fire the right missile. Interestingly, the system fires two missiles at one target, so that if one misses, the backup finishes the job. The radars keep talking to each other to track the moving target until it is destroyed. In total, the system can track 300 targets and engage 60 to 80 of them at once.
However, no weapon is perfect. The S-400’s biggest limitation is the curve of the Earth itself, which blocks radar beyond the horizon. Because of this, very low-flying cruise missiles or aircraft may not be spotted until they are quite close, sometimes only 40 km away. Still, the S-400 remains a fearsome guardian of India’s skies, growing stronger with every new addition.
-The writer is an award-winning science communicator and a Defence, Aerospace & Geopolitical Analyst. He is the Managing Director of ADD Engineering Components India Pvt. Ltd., a subsidiary of ADD Engineering GmbH, Germany. You can reach him at: girishlinganna@gmail.com. The views expressed are personal and do not necessarily carry the views of Raksha Anirveda
