India-Pakistan War: What is S-400 Air Defence System?

Why in News?

As India-Pakistan tensions flared after the May 7 precision strikes under Operation Sindoor, the spotlight once again turned to India’s air defence capabilities. Among the most formidable assets in India’s arsenal is the S-400 Triumf, known in Indian service as ‘Sudarshan Chakra’, a strategic deterrent and aerial shield against hostile incursions.

What is the S-400 Sudarshan Chakra?

The S-400 is a long-range surface-to-air missile (SAM) system developed by Russia’s Almaz Central Design Bureau. Considered one of the most advanced air defence systems in the world, it is designed to counter a wide spectrum of aerial threats including:

• Stealth aircraft
• Cruise missiles
• Ballistic missiles
• Drones and UAVs

Each S-400 squadron typically includes:

• 2 batteries, each with 6 launchers
• Command-and-control units
• Surveillance and engagement radars
• The ability to carry and launch up to 128 missiles

India’s S-400 Acquisition: Deal and Deployment

India signed a landmark ₹35,000 crore (approx. $5.4 billion) deal with Russia in 2018 to procure five squadrons of the S-400 system.

• As of 2025, three squadrons are fully operational
• The remaining two squadrons are expected by 2026
• These systems have already been deployed along strategic borders, including the western front with Pakistan and the northern sector facing China

What is the Price of  S-400 System?

India signed a ₹35,000 crore (approximately $5.4 billion) deal with Russia in 2018 to procure five squadrons of the S-400 system.

Capabilities of the S-400 System

The S-400 Triumf system is a multi-tiered air defence platform with four different types of missiles, each designed to intercept threats at various distances:

Tracking & Engagement

• Can track up to 160 aerial targets simultaneously
• Capable of engaging 72 targets at once
• Operates at altitudes of up to 30 km
• Uses phased array radars and advanced electronic warfare countermeasures
• Designed to operate even in contested electromagnetic environments

This makes it ideal for intercepting fast-moving, evasive, or stealthy threats, including ballistic missiles and fighter jets.

S-400’s Role in India’s National Defence

The S-400 has become a central part of India’s air defence strategy. In recent IAF exercises, the S-400 demonstrated its effectiveness by:

• Interdicting simulated enemy aircraft and missile targets
• Operating under electronic jamming conditions
• Coordinating with other surveillance and command systems such as AWACS and Netra

Its integration has dramatically enhanced India’s layered air defence network, especially important in times of conflict escalation like after Operation Sindoor.

Global Operators of the S-400

Apart from India and Russia, several other nations operate or have shown interest in the S-400 system:

Current Operators

• Russia: The primary developer and operator
• China: First foreign buyer, deliveries completed in 2018
• Turkey: Acquired in 2017, causing tension with NATO allies
• Belarus: Operates S-400 units, some managed by Russian personnel
• Algeria: Reportedly operating the system (unconfirmed)

Deployed in Conflict Zones

• Syria: Russia deployed S-400 units at Khmeimim Air Base in Latakia in 2015 following the downing of a Russian jet by Turkey.