Ukraine War, 31 May 2023: 'That' with Radars in Cities

Hello everybody!

During the night from 29 to 30 May, the Russians have run another strike with loitering precision guided munition (LPGM) of Iranian origin - see: foremost Shahed-136s, very few Shahed-131s (a.k.a. ‘Geran-2’ and ‘Geran-1’, respectively) - on Kyiv. Thus, would like to discuss few related points.

Initially, this strike was reported as ‘very focused’: as taking place within a very short period of time. Could be, but at least I’ve got no clarity in this regards. As far as I know, the air raid alert lasted from 23.30hrs on 29 May, until 04.30 on 30 May. Explosions from the greater Kyiv area were reported for some three hours.

According to official Ukrainian sources, it included 31 LPGMs, and these approached from two directions: ‘north and south’.

Ukrainians claimed 29 Shaheds as shot down: at least one of the two that came through should’ve scored a direct hit on the building housing the headquarters of the GRU MO (Ukrainian Military Intelligence). Wreckage of others came down in the Holosiivskyi and Podilsky Districts, causing damage to several buildings. The worst was a skyscraper (of which there are ‘none in Kyiv’….sigh…) with apartments in the Holosiivskyi District: this received a hit at one of uppermost levels, which set a flat on fire and killed one person (apparently a woman that went out to balcony to watch the ‘fireworks’….) Three were wounded.

Atop of this, the Russians have heavily shelled the Kherson (city) area, wounding five; and multiple parts of the Sumy Oblast (the latter came under strikes by artillery, multiple rocket launchers, and attack helicopters).

A screen-grab from a video released in the Russian social media, shown one of at least 8, more likely 29-32 UAVs that approached the south-western Moscow area yesterday. Mind the ‘canard’ aerodynamic configuration of this drone: that means, ‘fins are in front’, i.e. on this capture, the aircraft is flying ‘from the lower right towards the upper left corner’.

In turn, yesterday early in the morning, between 29 and 32 UAVs (the Keystone Cops in Moscow reported ‘just 8’) approached south-western Moscow. Several were either shot down or caused to crash (by means of electronic warfare, which caused widespread disturbance of the GPS-service in much of western Russia, all the way to the eastern borders of the Baltic states) in the Krasnogorsk District, and in the villages of Ilinskoye and Timoshkino, along the Rublyovka and Ilinskoye highways, and in the Odintsovsky District. ‘But’, one is known to have hit the ground close to Putin’s residence in the Ilyinka area. Below a map shown known places where UAVs either hit something or crashed (purple) or where explosions were reported (pink). ‘Only’ three UAVs are known to have actually reached Moscow (over 830km away from Ukraine): one hit a tall building in Atlasova Street (New Moscow), two others hit residential buildings in the Cheryomushki District (intersection of Leninsky Ave. with Udaltsov Street): one of the latter two (hit an apartment on the 14th floor) failed to detonate.

What would I like to discuss about this?

It appears many social media presences are insistent in wondering how comes ‘slow, loud, vulnerable’ UAVs and PGMs can ‘do such things’ - and are happy to ridicule both the Russian and Ukrainian air defences. And few others are venturing into a directly opposite direction, like, ‘ah, no problem for Patriot & Co KG GesmbH AG’ (read: Patriot and other modern surface-to-air missiles/SAMs)… or ‘S-300… S-350…S-400 are killing Ukrainian UAVs with ease’….

Actually….

Sure: Shaheds (and the UAVs as used for this strike on Moscow) are slow and loud. Indeed, seems that at least a few Ukrainians are calling the Russian LPGMs ‘mopeds’ because that’s how their (piston) engines sound. And, they’re moving at docile speeds of 80-120km/h. But, they’re also small and shaped for minimal radar-cross section. Means: while not ‘stealth’, they are hard to detect. Even more so: they are extremely hard to detect from ranges beyond 30-40km, and then while approaching big cities.

Here an example: this screen grab below is shown the ‘radar coverage’ of a radar system positioned (just for example) on the Sikorsky International Airport in southern central Kyiv.

For this example, I’ve set the radar range to 150km, because that’s something like ‘average value for long-range/early warning/surveillance radars currently in service. And I’ve set that radar antenna on a 20-metres-tall mast, which is quite high but something like ‘average’ between systems currently in service in Ukraine (to make sure: yes, I know, some of systems have antennas installed on 40-metres-high radar masts).

Now pay attention, please:

• red: is marking the areas where this radar could detect targets flying at an altitude up to 100m;

• orange is marking areas where this radar could detect targets flying at an altitude of up to 40m;

• yellow is marking areas where this radar could detect targets flying at an altitude of up to 20m;

• green is marking areas where this radar could detect targets flying at an altitude of up to 10m.

Obviously, the lower the LPGM (or UAV) is flying, the shorter the detection range. For the start, this is shortened already by the curvature of the Earth: this is why something flying at an altitude of 100m - like a Shahed - is de-facto ‘undetectable’ for a radar in position described above from a range beyond about 45km.

Usually, Shaheds are descending the closer they get to their target area. First to around 40-50 metres, then to less: 20-30m. Eventually, they end up flying between higher buildings (including ‘non-existing skyscrapers of Kyiv’….ho-hum). For a better insight, here a zoom-in at the same ‘radar coverage map’ of the Kyiv area as above. Obviously, the lower the LPGM flies the more problematic it is to detect. Indeed, it’s crystal clear that - depending on the direction from which the LPGM is approaching - a radar postioned at Sikorsky IAP is not going to detect it before it reaches downtown Kyiv.

The reason is that when Shaheds fly that low, its not only the terrain (like hills north-east and south-east of Kyiv) but also tall buildings and other constructions that are causing problems: indeed, they’re creating outright ‘blind spots’ in the Ukrainian radar coverage.

Of course, it’s safe (at least logical) to conclude that the PSU is preventing this by deploying so-called ‘radar pickets’: early warning/surveillance radar systems positioned outside the city, especially ‘down the threat axis’ - down major directions from which usual Russian attacks are coming in (like north-east, east, and south-east). For example, a radar with an antenna on a 20-metres-tall mast positioned atop of one of hills north of Brovary can provide a much better coverage: it’s got near unobstructed ‘view’ towards north-east, east, and south/south-east:

Conclusion is on hand that even SAM-systems supported by radars that can detect _high-flying_ targets at, for example, 150km away, are having hard times to detect a _low-flying_ target at, for example, 20-30km away. Indeed, even a radar with a 20-metres-tall antenna positioned at Sikrosky International is unlikely to detect any Shahed before this reaches the downtown Kyiv.

….which is why all the descriptions about Patriots ‘scything’ Shaheds are daydreaming. Indeed, when one closely monitors the Ukrainian social media, it transpires that the mass of Russian LPGMs is shot down by ‘flak’ (automatic anti-aircraft guns calibre 20-, 23-, 35-, and 40mm), by MANPADs, and even by small arms fire.

….which in turn means that - contrary to their ballistic-missile strikes - the Russian strikes with LPGMs are unlikely to impose ‘attrition’ - to deplete - stocks of Ukrainian SAMs.

However, they are very much helping the GRU (Russian military intelligence) to follow the work of Ukrainian ground-based air defences. The longer the PSU’s radars and SAM-sites are forced to power up, the more intelligence about them are the Russians collecting (with help of their COMINT/ELINT/SIGINT systems).

Finally: mind that all of this is valid for the Russian air defences in Moscow, too - which is one of reasons why the Russians went as far as to start positioning, for example, Pantsyr S1/S2 SAM-systems (SA-22 Greyhound) atop of tall buildings around the centre of the city. To grant them a ‘free field of view’, and, of course, a free field of fire, too. With other words: that’s no ‘joke’, but an indication the Russians are taking the threat of low-flying UAVs the way they should: very seriously.

On the contrary, Moscow is so far from Ukraine that the GUR MO (Ukrainian military intelligence) is learning very little from its own UAV strikes on the Russian capital. In this regards, only NATO’s reconnaissance satellites might be of some help - all provided, of course, it was really Kyiv that run this UAV strike on Moscow, and that Kyiv is informing NATO about such operations on time…