When Ukraine announced earlier this month that it had destroyed four Russian S-300 air defense systems and a radar station, military analysts were stunned.
These surface-to-air missile systems (SAMs) are very sophisticated and deadly pieces of equipment. Their loss will be greatly felt in Moscow, and experts will have to struggle to explain how forces in the south of the country caused such destruction.
That mystery may have been solved earlier this week when US officials said they had been supplying Ukrainians with High-Speed Anti-Radiation Missile (HARM) systems.
Little has been heard of this weapon class so far in the war. That could change soon as they are likely to play a central role in a Ukrainian counterattack in the south.
Anti-radiation missiles sound like something straight out of science fiction; perhaps responding to a nuclear explosion to protect civilians from nuclear catastrophe.
Unfortunately, missiles like the AGM-88 – presumably the US-supplied weapon – are not effective against this type of radiation. Instead, they are designed to pick up the radiated signals from ground-based SAMs and scan the sky for approaching fighters.
Left intact, SAMs deny a force “air superiority” and make it difficult to engage other ground targets such as command centers, airfields, and ammunition depots. Destroying such sites is a critical task in a military campaign and is known as Suppression of Enemy Air Defenses (SEAD).
Ukraine wants to turn recent small-scale counterattacks around Kherson into a broader counteroffensive to retake tracts of land and perhaps threaten Russia’s hold in Crimea.
To be successful, Kyiv’s forces must at least temporarily command the skies to assist their ground counterparts in advancing.
In order for jets to operate unmolested, the SAM threat must first be eliminated or at least reduced, which is where HARM missiles come in, which fly at around 2,200 km/h and are therefore difficult to shoot down.
There are three versions of the AGM-88. Two require the jet to exchange information with the missile, select a target, or respond to a previously unknown threat.
Ukraine does not operate Western aircraft and therefore cannot use these versions. The third variant must be programmed before the jet takes off.
This is not ideal and is based on very good information about where Russia has deployed its SAMs.
Western electronic surveillance aircraft such as the RAF’s RC-135W Rivet Joint are helping in this regard, patrolling the Black Sea and sucking up radar emissions from southern Ukraine to map Russian networks. (© Telegraph Media Group Ltd 2022)
Telegraph Media Group Limited 
https://www.independent.ie/world-news/europe/us-supplied-weapons-helped-ukraine-destroy-sophisticated-russian-air-defence-systems-41909231.html US-supplied weapons helped Ukraine destroy sophisticated Russian air defense systems