The S-400 Triumph is an air defence missile system developed by Almaz Central Design Bureau of Russia. The S-400 was developed as an upgrade of the S-300 series of surface-to-air missile systems and entered service in April 2007.
The S-400 Triumph air defence system integrates a multifunction radar, autonomous detection and targeting systems and anti-aircraft missile systems. The system also includes launchers, and a command and control centre and can simultaneously engage 36 targets.
The S-400 is capable of firing five types of missiles of varying ranges and altitudes to create a layered defence. The system can engage all types of aerial targets, including aircraft, unmanned aerial vehicles, and ballistic and cruise missiles. The system can track all types of enemy aircrafts from a range of 40 kilometers to 400 kilometers at an altitude of up to 30 kilometers.
The system can be deployed within five minutes and can also be integrated into the existing and future air defence units of the air force, army and navy.
The command and control system is equipped to process the air space surveillance data of the individual batteries and can control, monitor and prioritise airborne threats.
One S-400 system comprising up to eight divisions can control up to 72 launchers, with a maximum of 384 missiles. The S-400 system can move on roads at 60 km/h and off-road at speeds up to 25 km/h.
In 2016, India and Russia signed an Inter-governmental Agreement for the supply of five S-400 regiments, which are set to be deployed in early 2022. Apart from India, Russia has provided the S-400 Air Defence Missile System to Belarus, Turkey, Saudi Arabia and China.
Piyush Anand 
Aayush Pal