March 10, 2024: Russia has introduced a new S-500 air defense system that is designed to do things the current S-400 cannot do. That means the S-500 can defend itself from attack, something which the S-400 has been increasingly unable to do in Ukraine. The S-500 is purportedly able to deal with threats that have not been invented yet, citing new types of hypersonic missiles in development. Given the problems the S-300 and S-400 systems have had in Ukraine, Russia mentioned sending S-500 to deal with aerial threats in Ukraine as well as the Ukrainian ability to deceive and destroy S-400 systems deployed near the Ukrainian border and Crimea. The loss of several S-400 batteries led Russia to withdraw S-400 batteries to defend vulnerable targets deep inside Russia that were being attacked by long range Ukrainian UAVs.

Russia’s most modern air defense system was the S-400 until the S-500 was introduced. The current version of the S-400 has a radar that can detect targets up to 400 kilometers away and launch S-400 missiles to hit targets up to 75 kilometers distant. Unfortunately, most modern jet combat aircraft carry an array of countermeasures to defeat missiles fired at them from the ground or other aircraft. In addition to surface-to-air missiles (SAMS) fired from the ground, warplanes also have to worry about missiles fired from jet fighters which are often more effective than SAMs. At the same time, Russia has found that their S-400 missiles are effective against ground targets, which can be hit at distances of up to 350 kilometers. Russia developed the 48/6DM missile for the S-400 system and described the missile as effective against air targets but able to accurately hit ground targets up to 230 kilometers away. The warhead weighs 180 kg and contains enough explosives to be effective against ground targets that are usually major Ukrainian cities. These places are often defended by American Patriot, which often succeed in intercepting Russian air defense missiles used against ground targets. The S-500 can use the 40N6 missiles the S-400 batteries are armed with as well as the new 77N6 missiles developed for the S-500 system. It is unclear if Russia is going to try and use S-500 batteries in areas where the S-400 system failed. Ukraine is an actual wartime test of how effective combat systems are and the S-400 was found deficient when it came to effectiveness and reliability against a determined enemy.

The U.S. Navy has also modified its SM series of air defense missiles to hit surface, as in ships, targets. These missiles can also be used against ground targets not too far from the shoreline. The 1.3 ton SM-6 warhead weighs less than a hundred kg. That’s not a lot of explosives, but that warhead is accompanied by a large portion of the missile body which adds to the destructive effect. What makes that possible is that the missile hits the targets at speeds similar to rifle bullets. When using a high speed missile against a warship, the damage is extensive. The Navy verified this during a SINKEX, or sinking exercise where a retired warship is used as the target. In this case the target ship was a recently retired 4,000-ton frigate. The warhead traveling at high speed did enough damage to render the target ship unable to move or fight. This is what would happen to an enemy ship hit with an SM-6 missile in wartime.

This was consistent with results from earlier SINKEX tests using the older SM-2 missile, which entered service in 1980 and was also designed for use against surface targets as well as aircraft. The max range of an SM-6 against a surface ship is 240 kilometers. The longer range and higher speed of the SM-6 make it particularly effective against other ships.

The SM-6 is basically the existing SM-2 anti-aircraft missile with the more capable guidance system of the AMRAAM air-to-air missile, as well as general improvements in the electronics and other components. The SM-6 is a 1.5 ton, 6.55 meter long, 533mm diameter missile. It has a maximum range of 240 kilometers and an altitude effectiveness of 33 kilometers, or 110,000 feet.

The older SM-2 is a 1.35 ton, 8 meter long missile with a max range of 190 kilometers and max altitude of 24.4 kilometers, or 80,200 feet. The main change for the SM-6 is the guidance system which is self-contained and will seek out any target it comes within range of. The SM-2 uses a semi-active guidance system, which requires that a special targeting radar light up the target with a radar beam, which the SM-2 guidance system detects and homes in on. The active guidance system of the SM-6 is harder to jam and can home in on targets beyond the range of targeting radars. The SM-6 can attack anti-ship missiles as well.

The SM-6 took nine years to develop and has been in production since 2011, with plans to obtain up to 1,800 missiles at a cost of $4.3 million each. SM-6 will replace many of the SM-2 missiles carried by American and Australian warships. Navy anti-aircraft missiles, including the SM series, have long been used as anti-ship weapons.

Meanwhile, the navy has been continuing years of improvements in the Aegis radar and fire control system that controls SM-2, SM-6, and the smaller SM-3 anti-missile version. The SM-3 can destroy ballistic missiles and low orbit satellites. Aegis equipped ships began getting version 4.0 of the Aegis anti-missile software in 2013 and the 5.0 upgrade made the anti-missile capabilities a standard feature of Aegis software. New destroyers are having anti-missile Aegis software installed as standard equipment. Much of the anti-missile capability of the original Aegis anti-aircraft system came from upgrades to the Aegis software.

The Aegis anti-missile system has had a success rate of over 80 percent in knocking down incoming ballistic missile warheads during test firings. To achieve this, two similar models of the U.S. Navy Standard anti-aircraft missile are in service, in addition to the Aegis radar system modified to track incoming ballistic missiles.

The RIM-161A, also known as the SM-3 or Standard Missile 3, has a range of over 500 kilometers and max altitude of over 160 kilometers. Standard 3 is based on the anti-missile version of Standard 2 Block IV. This SM-3 missile has a shorter range than the SM-2, which can destroy a warhead that is more than 200 kilometers up. The SM-3 is optimized for anti-missile work, while the SM-2 Block IV was designed to be used against both ballistic missiles and aircraft. The SM-2 Block IV also costs less than half of what an SM-3 costs, so going after aircraft with SM-3s is discouraged unless absolutely necessary.