How is the S-400 air defence system technically superior to any other system presently available in the world?

The S-400 Triumf is a mobile, surface-to-air missile system (SAM) designed by Russia. It is the most dangerous operationally deployed modern long-range SAM (MLR SAM) in the world, considered much ahead of the US-developed Terminal High Altitude Area Defence system (THAAD) and Patriot PAC-3. 

Comparative Analysis of S-400 with other advanced defence system: 

S-400 Triumf (Russia)

• Capable of firing any aerial target within a range of 400km.
• It has an ability to simultaneously track upto 160 objects in 600 km.
• It can intercept and shoot the moving targets with a maximum speed of 17km/hr.
• It can be assembled and deployed within five minutes.
• It is economical as it costs approximately only $500 million. 

Patriot PAC-3 (The Phased Array Tracking to Intercept of Target (PATRIOT) Advanced Capability- Three) USA

• Ability to intercept aerial targets at a range of 180 km and of launching ballistic missiles upto a range of 100 km.
• It can track only 36 objects simultaneously.
• Whereas, it can intercept and shoot moving targets with a maximum speed of only 8km/hr.
• It takes around 25 minutes to get assembled.
• The estimated cost of PAC-3 is around $1billion. 

THAAD (Terminal High Altitude Air defence) USA 

• It can fire only one type of missile (ballistic)upto a range of 150-200 km. It cannot engage aerial targets.
• It has a single layer defence. Only one object at a time.
• It cannot intercept even a fighter jet.
• It cannot be deployed as fast as PAC-3 or S-400.
• The estimated cost of THAAD is $3 billion. 

Hence S-400 is technically superior to its counterparts and this is the reason why India opted for S-400 despite US apprehensions. 

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Several other features of S-400 such as:

1. Flexibility to be integrated into existing and future air defense units.
2. Improved electronic countermeasures that prevent the attempt of jamming while detecting low signal targets.
3. Hit to kill technology

Other Russia's Military Equipment Deployed by India:

1. Navy: The Navy's only active aircraft carrier INS Vikramaditya is from Russia. A nuclear attack submarine Chakra II is also in service.
2. Army: Army’s T-90 and T-72 main battle tanks.
3. Air Force: IAF’s Su30 MKI fighter. 

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