Integrated air defence systems (IADS) are a key feature of modern warfare. IADS – like the one Russia has deployed on NATO’s Eastern Flank and which China is creating within the First Island Chain – are complex, multilayered defence systems incorporating a range of ground-based and aerial sensors, as well as surface-to-air missile (SAM) systems. Modern SAM systems are highly mobile, able to set up and pack away in minutes prior to and after firing. They are also supported by point-defence systems, electronic warfare assets and deception measures such as decoys. This makes them very difficult to reliably track, target and destroy from long ranges. They are also increasingly equipped with digital radars capable of frequency-hopping, offering much better resistance to jamming interference and also making them harder to detect when in operation.
IADS are not in themselves a new phenomenon. However, the SAM systems and radars which make up modern IADS are much more capable than previous generations. The territory which they can cover is also much larger than in previous generations due to several very long-range SAM systems such as the Russian S-400 (SA-21 in NATO terminology), S-300V4 (SA-23) and Chinese HQ-9. These systems mean that Russia and China, as well as other overseas users of such systems, can threaten to restrict freedom of manoeuvre well outside their own land borders. Advertised maximum range for SAM systems is usually for large, non-agile targets like tankers flying at medium-high altitudes. Against agile, lower flying targets practical ranges are significantly shorter. However, the long-range SAM systems are connected to a larger number of medium- and short-range SAM systems, as well as other sensors such as those carried by AWACS aircraft. Drawing on these external sources of target data allows systems like the SA-21 to fire their own long-range active seeker missiles against targets far beyond their own radar-horizon. Therefore, for Western air forces, planning operations against modern IADS is more complex and challenging than against a standalone system – even a very modern one like the SA-21.
The key conclusions are:
• Russia’s IADS threatens to keep NATO airpower at arm’s length and predominately occupied with the task of suppression of enemy air defences (SEAD) during the initial critical phases of any armed clash. The strategic SA-21 and SA-23 long-range SAM elements coordinate and are supported by a range of medium-range systems including the SA-17, and shorter-range and point-defence systems like the SA-15 and SA-22. The medium- and shorter-range systems would doctrinally tend to be attached to ground force units closer to the frontlines, whilst the strategic SAMs are used to protect key facilities. However, they operate functionally as part of the same IADS and present a challenging opponent for NATO air forces. The question is not whether the Russian IADS could eventually be degraded and rolled back, but whether NATO forces could do so quickly enough to avoid defeat on the ground while deprived of regular close air support in the meantime.
• China’s IADS is less well integrated than Russia’s but is more heavily distributed and mobile. It is comprised of land-based HQ-9 and SA-21 long-range and multiple medium-range SAM systems on the mainland as well as on artificial reefs, and an increasingly potent naval component in the shape of People’s Liberation Army Navy major surface combatants with the navalised HHQ-9 series. China is also pursuing multiple aerial and ground-based exotic radar and multi-spectral sensor technologies to support both its IADS and the People’s Liberation Army Air Force. In conjunction with increasing aerial capabilities, the Chinese IADS presents a dynamic and growing challenge to the freedom of action of the US and its allies near the Chinese mainland.
• Chinese and Russian air defence systems continue to proliferate globally, along with the electronic warfare assets and integration assistance required to turn SAM systems into a capable IADS. This means that a modern SEAD capability will soon be required in far more military situations than the peer-clash scenario of a conflict with Russia or China.
• There are multiple potential ways to approach the problem of tackling hostile SAM systems, including stand-off attacks with cruise missiles, stand-off or stand-in jamming, or being able to get close enough without being detected to directly attack or bypass threat systems through stealth capabilities. However, against a modern IADS, a combination of these techniques, along with the ability to detect, classify, track and pass target data to other coalition assets without being shot down in the process, will be required. These capabilities are too expensive for any one country aside from the US to operate alone. If the Alliance wants to improve its ability to conduct effective SEAD operations and reduce the threat from modern IADS, it will need to cooperate and exercise collectively, as well as purchase new equipment.
The report is available at https://rusi.org/sites/default/files/20191118_iads_bronk_web_final.pdf