According to an interview on CBS published on September 24, 2021, Turkish President Recep Tayyip Erdoğan has announced that Turkey plans to purchase more Russian-made S-400 air defense missile systems.
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Transporter Erector Launcher unit of Russian-made S-400 air defense missile system. Picture source Army Recognition)

The S-400, NATO reporting name SA-21 Growler, is one of the most popular air defense systems in the world, which is in service with Algeria, China, Russia, and Turkey. Other countries have also shown interest to acquire the S-400, including Belarus, India, and Saudi Arabia.

The S-400 Air Defense system is able to autonomously detect, track, engage and destroy targets that may be manned or unmanned and it is also able to effectively target ballistic targets as well. The S-400 has been deployed in Syria to protect Russian military bases.

The S-400 Triumph is designed to engage, ECM, radar-picket, director area, reconnaissance, strategic and tactical aircraft, tactical and theatre ballistic missiles, medium-range ballistic missiles and other current and future air attack assets at a maximum range of 400 km, and an altitude of up to 30 km. The S-400 Triumph can also destroy Tomahawk cruise missiles and other types of missiles, including precision-guided ones, as well as AWACS aircraft, at ranges of up to 400 km.

Russia and Turkey officially confirmed the signing of a contract for delivery of S-400 Triumph SAM (surface-to-air missile) systems in 2017. Unlike the first foreign customer — China, the Turkish side is to receive two S-400 regiment sets instead of one. In May 2019, 100 Turkish soldiers started to study learning of S-400 Triumph SAM systems in Russia.

Deliveries of Russia’s S-400 missile systems to Turkey began on July 12, 2019. According to the Turkish Ministry of National Defense, three military transport aircraft delivered several prime movers and launcher units for S-400 to Murted Air Base.