HERE IS AN ROUGH ESTIMATION OF SIPER'S POTENTIAL CAPABILITY AGAINST STEALTH.
My calculation simlpy based on oficial press released information of both f35 and aselsan's STR. ( that's as far as i can get )
so firstly, f35 isn't all band stealth. Some fan boy gonna claim that. but that's not correct. Out side the S and X band domain f35's low observablity ( or for that matter, any stealth fighter's low observability ) decrease. So, the US Air Force's official press release about f35's RCS being size of a golf ball which mean 0.0015 is mostly related to S and X band domain.
Remamber, all the fire control radars siting on the noses of fighters are X band. And in case of ground based fire control radars they are also mostly between X and S bands and lately there are some are C band. ( note, I am not talking here about target illumination radars ).
Now let's talk about siper, 'tiny' ku band seeker can acquire low observable target if there is a two way data link which can guide the interceptor until the very last moment. ( So this isn't a big issue. And I think siper has a two way data link ) and also, in the future blocks siper is likely to gain a ka band seeker just like the one on aster 30 block 1nt. Which is very useful in acquiring low RCS targets.
Now, about STR, it can detect a Katyusha-type artillery rocket from 100km according to the defenceturkey.
AND CFAKR IS STATED TO HAVE SIMILAR BUILDING BLOCKS OF STR AND AIR RADARS.
which is not strange at all, as we see in some new gen FCRs as it can also act as weapon locating radar.
For example thales ground fire or ELTA ELM-2084. Both has 100km range for weapon locating capability.
https://www.google.com/url?sa=t&sou...EQFnoECAkQAQ&usg=AOvVaw108cQ2jtyvA-U023jTRnNo
now, katyusha is 122mm rocket with a typical RCS of 0.1m. So when we do the math with f35's RCS to determine the detection and tracking range with fourth roots calculation, it is important to remamber that f35's said RCS ( 0.0015 ) is not all aspects but a frontal one. ( which is very useful against another fighter in head to head mode )
However, when the ground based CFKAR looks at f35 from a below Angel some surface area on the jet will be exposed which has less RCS than frontal section. And It is likely to be then somewhere in between 0.008m and 0.05m. So when we do the math based on that the detection and tracking range of an f35 for CFAKR will be somewhere in between 60 to 80 km.
Note, this is my personal opinion based on my personal knowledge. So don't take it too seriously.