India’s Ministry of Defence (MoD) signed a contract worth Rs 445 crore ($46 Million) with Russia’s JSC Rosoboronexport for the procurement of Tunguska air defence missile system for the Indian Army on March 27. These cutting-edge missiles will enhance India’s multi-layered air defence capabilities against aerial threats including aircraft drones and cruise missiles. The agreement will further strengthen the India-Russia strategic defence partnership.
Meanwhile, the Defence Acquisition Council (DAC) headed by Defence Minister Rajnath Singh on Friday cleared a proposal to procure five additional S-400 long range surface-to-air missile systems for the Indian Air Force (IAF) from Russia, months after the S-400s demonstrated their outstanding capability during “Operation Sindoor”.
Importance of AD Systems in Modern Wars
Ongoing conflicts in Ukraine and West Asia have re-emphasised the importance of potent Air Defence (AD) systems. These are critical, multi-layered, and technology-driven frameworks that play a decisive role in modern warfare by protecting assets, denying enemy air superiority, and facilitating offensive operations. Modern AD Systems have transitioned from purely defensive tools to strategic enablers.
As part of the “layered defence strategy”, modern AD systems (S-400, Patriot, and Iron Dome) combine long-range, medium-range, and short-range radars and missiles to protect high-value targets, cities, command and control centres, military assets, and nuclear sites against varied threats. In addition to combat aircraft and missiles, AD systems are essential for detecting and destroying small, inexpensive drones, which are used to saturate, deceive, and damage defences as part of the counter-drone capabilities.
A good AD system can impose “Air Denial” even by a technically inferior air force, and force enemy aircraft to operate at safer distances, restricting their ability to support ground operations. Advanced systems like the S-400 can force enemy aircraft, such as Airborne Early Warning (AEW&C) and Flight Refueller Aircraft (FRA) to stay further away from the battlefield.
Suppression of Enemy Air Defences (SEAD) has thus become an important mission for air operations. The modern AD systems have to adapt to engage emerging threats such as high-speed ballistic missiles, ultra-low flying cruise missiles and hypersonic threats. Modern AD is also integrated with Electronic Warfare (EW) systems that can jam or blind enemy sensors and guidance, providing a “soft-kill” alternative to physical destruction.
Mobility is important to enable “Shoot and Scoot” capability by allowing them to change positions rapidly to avoid detection. Possessing a robust AD shield acts as a major deterrent and gives nations a stronger hand during diplomatic and military crises. Modern AD operates within an Integrated Air and Missile Defence (IAMD) ecosystem, also called the “system of systems” that connects radars, satellites, weapon platforms, and in-flight weapons, to provide a real-time, comprehensive air picture. Future development focuses on Directed Energy Weapons (DEWs) to counteract the high cost of interceptor missiles, with some systems potentially costing as little as $2,000 per shot.
Countries are investing in domestic AD technologies (India’s Akash and Kusha AD Systems) to reduce dependence on foreign imports and ensure the ability to produce systems at scale. In contemporary combat, AD systems determine the ability of a military to operate and survive. As seen in recent conflicts, the ability to protect key assets and deny the airspace to an adversary is often the deciding factor in war.
2K22 Tunguska
The 2K22 Tunguska (NATO: SA-19 Grison) is a Soviet-era tracked, self-propelled, anti-aircraft system that combines guns and missiles for short-range air defence (SHORAD). It is a unique hybrid platform that combines both surface-to-air missiles (9M311, 10 km range) and high-speed anti-aircraft twin 30 mm auto-cannons for close-in defence, firing up to 5,000 rounds per minute, effective from 200m to 4km against air targets. The single chassis provides comprehensive protection. Its 360-degree radar can detect threats up to 18 km away, along with a digital fire control system for high precision.
The missile component can strike targets at altitudes of up to 3,500 meters, filling the gap between man-portable systems and long-range high-altitude batteries. All-terrain tracked armoured chassis, allows it to keep pace with tanks and infantry fighting vehicles across rugged terrain and in diverse weather conditions. The system includes back-up optical tracking capabilities, allowing engaging targets even if the radar is being jammed by enemy Electronic Warfare.
The system is designed to provide low-altitude air defence for infantry and armoured regiments. Its main objective is to protect ground troops on the move against low-flying targets, including attack helicopters and close-support aircraft, cruise missiles and precision-guided munitions, and tactical drones and Unmanned Aerial Vehicles (UAVs).
As modern warfare shifts toward drone-heavy tactics, for India, Tunguska’s rapid-fire guns provide a cost-effective and highly efficient solution to swarm threats. It will strengthen India’s multi-layered air defence network, acting as a vital shield for mobile army columns that are vulnerable to sudden aerial strikes.
S-400 Missile System “Sudarshan Chakra”
The S-400 is a Russian mobile SAM system developed in the 1990s by Russia’s NPO Almaz as an upgrade to the S-300 family of missiles. The S-400 joined Russian armed forces in 2007. The system is complemented by its successor, the S-500. S-400 system has four radars and four sets of missiles covering different ranges and vertical bubble. The maximum target detection range is 600 kilometres and targets can be engaged as far as 400 kilometres. The five batteries of S-400 contracted by India in 2018 cost $5.43 billion including with reserve missiles.
All the sub-units are data-linked and controlled by a central command and control system with sufficient redundancy. The system is capable of layered defence and integrates with other Indian air defences. One system can control 72 launchers, with a maximum of 384 missiles. All missiles are equipped with directed explosion warheads, which increases the probability of complete destruction of aerial targets. The system is designed to destroy aircraft, cruise missiles, and ballistic missiles, can also be used against ground targets. It can engage targets up to 17,000 km/h or Mach 14. It can intercept low flying cruise missiles at a range of about 40 km due line-of-sight requirement. The anti-ballistic missile (ABM) capabilities of the S-400 system are near the maximum allowed under the (now void) Anti-Ballistic Missile Treaty. The number of simultaneously engaged targets by the full system is 36.
The system ground mobility speed is close to 60 km/h on roads and 25 km/h cross-country. It takes 5 minutes to be operational and fire when ordered while driving. Otherwise system response time is just 10 seconds. Time between major overhauls 10,000 hours. The Service life is at least 20 years.
In Russia the system was made operational around Moscow in 2007. Russia reportedly deployed S-400 in Syria. The system has been widely used in the on-going conflict in Ukraine, and claimed to have shot-down many aircraft. Meanwhile Ukraine has reportedly used Western weapons, mainly U.S.-made ATACMS missile, to hit S-400 units on the ground.
Belarus has unspecified numbers of S-400 units. Deliveries to China, of the six batteries ordered began in in January 2018. 4 batteries consisting of 36 fire units and 192 or more missiles were delivered to Turkey. Algeria is another operator. Some other countries like Iran, Egypt, Iraq, and Serbia, have also shown interest. South Korea is developing the KM-SAM, a medium-range SAM system based on technology from S-400 missiles, with assistance from NPO Almaz.
As of March 2026, Russia had delivered three out of five ordered S-400 systems. The fourth unit was undergoing final testing, with delivery expected in May 2026, and the final (fifth) system is expected to be delivered by November 2026, adhering to an accelerated schedule. India took deliveries despite American threat of CAATSA (Countering America’s Adversaries Through Sanctions Act). The recent conflict revealed the rough location of two systems, one each being in Punjab and Gujarat. As per open sources, the third is somewhere in the east. The systems were tested in various Indian military exercises.
Why India Needs More S-400s
India is a continental sized country. India has a total geographical area of approximately 3.287 million square kilometres. India has a total land border of approximately 15,200 km, bordering seven nations. The total coastline measures 7,516 km. India is among the most threatened nations with serious boundary disputes with nuclear armed neighbours, with both of whom India has had military conflicts. A much smaller country, Israel (land area 20,770 square kilometres) has around 10 mobile Iron Dome defence batteries.
Thus India’s decision to go for 5 additional S-400 systems make imminent sense. In the long run India will require close to 20 such systems. These will be achieved by inducting the indigenous Kusha AD system which will be of S-400 and later S-500 class.
To Summarise
At the 16th L.M. Katre Memorial Lecture in Bengaluru, in August 2025, IAF Chief, Air Chief Marshal AP Singh lauded the S-400 air defence system as a potent deterrent. The S-400s lethality, and the accuracy of BrahMos supersonic cruise missiles had a game changer role in Operation Sindoor. He highlighted the system’s operational success, strategic value in protecting Indian airspace, and contributed to maintaining an edge in regional air security. Despite geo-political challenges, the IAF had maintained interest in acquiring additional S-400 systems to further strengthen air defence. Clearly the side with better air defence systems could inflict significant damage and deter the adversary from carrying out strikes.
For long, IAF strategy, tactics and therefore inventories have been designed for offensive-defence. During Operation Sindoor, nearly five Pakistani fighter aircraft were shot down in the air by Indian S-400. Interestingly, the S-400 achieved its farthest kill ever by destroying a High Value Air asset (HVAA) at reportedly 314 kilometres. These were over and above the aircraft destroyed during airfield strikes, Air Chief had said.
During its retaliatory strikes on Indian military targets, Pakistan claimed that two S-400 systems at Adampur and Bhuj were neutralised. International media acknowledged that all such claims were false. It was later revealed that after firing their missiles the S-400 elements were moved as part of standard tactics. Immediately after the ceasefire, Indian Prime Minister Modi visited Adampur and addressed the personnel with the S-400 launcher forming the background. A similar visit was made by Defence Minister Rajnath Singh to Bhuj.
Few systems got universal praise during Operation Sindoor. These included the S-400 AD System, India’s indigenous Akash AD system, the DRDO 4D (Drone, Detect, Deter, Destroy) counter-drone system, and the BrahMos anti-surface missiles. French Scalp missile also proved extremely accurate and destructive.
Aerospace has become the primary means of prosecuting war. India-Russia relations are time-tested. Nearly 60 percent of IAF aircraft are of Russian origin. Russian platforms and weapons with Indian armed forces have performed exceedingly well for many decades, since the MiG-21s of 1960s. The S-400 and Su-30MKI–BrahMos combination have excelled in Operation Sindoor. Could S-500 (600 km) be the next acquisition? Will India select the Su-57 fifth-generation aircraft and Make-in-India? Can Russia help accelerate Indian nuclear submarine program? Should India acquire the “AWACS Killer” Russian R-37M AAM and the two work on futuristic long-range aerial missiles? Should there be more work together on Su-30MKI upgrade. Can the two enter into a joint-venture for Kamikaze drones required by both sides in large numbers, and India can help scale up production. Clearly Sky is no more the limit.
Note: The article was originally written by the Author for Russia Today 1st April 2026; it has since been updated.
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