The S-400 Triumf (Russian: C-400 ?????? – Triumf; translation: Triumph; NATO reporting name: SA-21 Growler), previously known as the S-300 PMU-3,is a mobile surface-to-air missile (SAM) system developed in the 1990s by Russia's NPO Almaz as an upgrade to the S-300 family of missiles. The S-400 was approved for service on 28 April 2007 and the first battalion of the systems assumed combat duty on 6 August 2007. The system is complemented by its successor, the S-500.

Development

The 48N6E3 missile used by the S-400

The development of the S-400 began in the early 1980s to replace the S-200 missile system, but was rejected by a state commission due to high cost and inability to address the threat of cruise missiles. In the late 1980s, the programme was revived in under the codename Triumf as a system capable of engaging aircraft at long range plus cruise missiles and stealth aircraft. The Soviet government approved the Truimf programme on 22 August 1991, but the collapse of the Soviet Union put development into limbo. It was announced by the Russian Air Force in January 1993. On 12 February 1999 successful tests were reported at Kapustin Yar in Astrakhan, and the S-400 was scheduled for deployment by the Russian army in 2001. The S-400 was officially revived on 7 July 1999, albeit as a modernization of the S-300PM rather than an S-200 replacement. Alexander Lemanskiy of Almaz-Antey was the Chief Engineer on the S-400 project.

In 2003, it became apparent that the system was not ready for deployment. In August, two high-ranking military officials expressed concern that the S-400 was being tested with older interceptors from the S-300P system and concluded that it was not ready for deployment. The completion of the project was announced in February 2004. In April, a ballistic missile was successfully intercepted in a test of the upgraded 48N6DM missile. The system was approved for service by the government on 28 April 2007. Russia had accepted for service the 40N6 long-range missile for the S-400 air-defence system, a source in the domestic defense industry told TASS news agency in October 2018.

The S-400 Triumf and Pantsir missile system can be integrated into a two-layer defense system.