In March 2023 we published an article about Russia’s 12A6 Sopka-2 ground-based air surveillance radar. Since the article’s publication, new information has come to light regarding this system and its performance.
Armada published its initial analysis of the Sopka-2 as part of our ‘Russian IADS Redux’ series on that country’s strategic Integrated Air Defence System (IADS). By means of background, and to refresh memories, deployment of the Sopka-2 started in 2014. Taking its name from the Russian translation for ‘hill’, the radar was designed to support military and civilian air traffic control. The Sopka-2 combines the tasks of several legacy radars deployed by the Russian Air and Space Force (RASF). It contains Primary and Secondary Surveillance Radars (PSR/SSR). The PSR provides range, azimuth and elevation information and the SSR provides identification friend or foe data.
Manufacturer-provided information states that the Sopka-2 is an S-band (2.7 gigahertz/GHz to 2.85GHz) ground-based air surveillance radar. It has a range of circa 243 nautical miles/nm (450 kilometres/km). Open-source information says the radar can detect a target at circa 328,084-feet/ft (100,000-metres/m) altitude at circa 65nm (120km). Targets at circa 32,808ft (10,000m) altitude can be detected at ranges of 216nm (400km). Importantly, these figures do not specify the Radar Cross Section (RCS) of the target. Target RCS will influence detection ranges and altitudes.
According to EW Analytics LLC the Sopka-2 feeds its data into what the RASF call Aviation Guidance Points (AGPs); the equivalent of ground-controlled interception centres. AGPs are used to control fighters intercepting air threats. The radar is also likely to feed data into mobile RASF VIP-117M3 air command and control systems. Both the AGPs and VIP-117M3s use R997-1M Very/Ultra-High Frequency radios (V/UHF: 30 megahertz/MHz to three gigahertz) for fighter communications.
Sopka-2 radars do not appear to be deployed alone at the AGPs. EW Analytics LLC’s analysis has determined that 1RL131 Terek (North Atlantic Treaty Organisation reporting name P-18 Spoon Rest-D) VHF ground-based air surveillance and PRV-13 (Odd Pair) S-band (2.620GHz to 2.830GHz) height-finding radars are collocated with the former. The Sopka-2 is advertised as having only rudimentary electronic counter-countermeasures. It is possible that the 1RL131s and PRV-13s are used as back-ups should the Sopka-2 experience jamming. These latter radars may also provide additional track data to enrich the AGP’s Recognised Air Picture (RAP).
Belarus and Ukraine
Russian sources stated that the RASF planned to acquire enough Sopka-2s to cover the whole country with an initial 20 being delivered by the end of 2014. Belarus activated a single Sopka-2 radar in January 2021 at Baranovichi airbase. This facility is around 150km (93 miles) north of the country’s border with Ukraine. Taking the radar’s location into account, it could look 162nm (300km) into Ukraine’s airspace. EW Analytics LLC’s information says that an AGP is collocated at the airbase. The Sopka-2 there almost certainly feeds track data into this aviation guidance point.
Russian media reports from March 2022 said that Su-35 (NATO reporting name Flanker-E) combat aircraft fighting in Ukraine had flown from Baranovichi. It would not be surprising if these aircraft were under the control of this AGP. The same facility is reportedly home to a 56N6E Protivnik-GE L-band (1.215GHz to 1.4GHz) ground-based air surveillance radar. The relationship between the Sopka-2 and 56N6E remains unknown. It is possible that the two radars provide redundancy in case one is unserviceable for any reason, for example if the Sopka-2 is jammed. They may also both be used to provide as rich a RAP as possible.
EW Analytics LLC recently shared with Armada that the Belarussian Ministry of Defence has signed a contract with the radar’s manufacturer for a Sopka-2 modernisation. The exact nature of this modernisation is unknown at present. Moreover, reports emerged that on 9th August Belarussian air defenders detected 13 Uninhabited Aerial Vehicles (UAVs) that entered Belarus’ airspace from Ukraine. The UAVs were shot down over Kostyukovichi in eastern Belarus.
The Sopka-2 radar at Baranovichi is located around 397km (246 miles) west of Kostyukovichi. The UAVs are likely to have been within the radar’s 243nm instrumented range. It is possible that the Sopka-2 detected and tracked these aircraft. Nevertheless, given the radar’s advertised range resolution of 250m (850ft), it is possible the radar did not detect individual UAVs. Instead, the targets may have shown up as a single plot. The extent to which the Sopka-2 was involved in this interception remains unknown. That said, the upgrade programme, and ongoing deployment of the radar across Russia, illustrates that it is very much a key component in the Belarussian and Russian IADSs.
by Dr. Thomas Withington
