In mid-2020 Russia introduced a new air defense system that specializes in defending against short range ballistic missiles. Called Abakan, it is an upgrade of the earlier Antey-2500 and Antey-4000 ABM (anti-ballistic missile) systems. These are produced by the same state-owned firm that developed and manufactures the primary Russian air defense systems like the S-300, S-400 and older S-200 systems. In development is the S-500 system, which uses a new missile that turns the Antey-4000 into Abakan. Russia often does this, using a component of a new system to upgrade an existing system. The new 9M82MDE missile has a range of 350 kilometers and is quick and accurate enough to intercept short range ballistic missiles. The 9M82MDE is larger than previous missiles used by Antey-2500/4000 systems and requires a new launcher/transporter; the 51P6E2. This 10×10 vehicle carries two missiles in storage/launch cannisters as well as a guidance radar that is also raised into position behind the crew (of two) cab while the two 9M82MDE missiles are raised into position at the rear of the vehicle.
The Antey-2500/4000 systems use shorter range versions of the older S-300 missile, which carry four of them in a smaller launch vehicle that does not include a radar. All three systems also rely on a larger AESA search radar. There are improved versions of these radars for the Antey-2500/4000 and Abakan systems.
Russia designed these systems to defend against the latest generation of Israeli air-to-ground missiles that go high before coming down on the target like a ballistic missile. These Israeli missiles have proved very difficult to intercept in Syria and it is unclear if the Russians have tried out Antey-2500/4000 in Syria, where the Syrians are quite vocal about the inability of the older Syrian S-200 systems that regularly fail to intercept the Israeli air launched “ballistic missiles.”
The S-300 and S-400 are similar to the U.S. Patriot, and expensive. Russia is now offering to export the S-400, despite all the advanced technology in it. The S-400 missiles weigh 1.8 tons each, are 8.4 meters (26 feet) long and about 50cm (20 inches) in diameter. The missiles have a range of some 400 kilometers, and can hit targets as high as 32 kilometers (100,000 feet). The missile has a 145.5 kg (320 pound) warhead. The target acquisition radar has a range of 700 kilometers.
The S-400 has over five times the range of the U.S. Patriot, weighs twice as much and claims the ability to detect stealthy aircraft. The S-400 also has an anti-missile capability, which is limited to shorter range (3,500 kilometers) ballistic missiles. That would mean a warhead coming in at about 5,000 meters a second. The longer the range of a ballistic missile, the higher its re-entry speed. S-500 can handle faster, and longer range, ballistic missiles but the complete S-500 system is not yet ready for service.
The S-400 system actually has two types of missiles, one of them being smaller, with a shorter range (120 kilometers). These are deployed four to a launcher, like all other S-300 systems. The S-400 has no combat experience, but U.S. intelligence believes that the tests these systems underwent indicate it is a capable air defense weapon. Just how capable won't be known until it actually gets used in combat.
The S-400 is sometimes described as an improved version of the S-300. Basically, it is. That is why customized versions of the S-300 missile were used for Antey-2500 and Antey-4000. Abakan uses the larger S-500 missile. This is how Russia prefers to develop weapons, making incremental improvements on a basic design, and doing so for decades if the system continues to be successful. The S-500 is a break from that pattern.