Radar is inconsistent for me. I'm unable to see targets I should be able to, but do occasionally have contacts pop up and can successfully lock them when they do. There seems to be no predictable pattern to whether it'll work or not.

same for, any mode any target, even in ideal conditions

OBERST78, can you provide a short track from the Caucasus map with the exact description of the issue?

Scenario recreated in the Caucasus. As seen in the video, the planes are not displayed in the radar. If they appear, they cannot be docked.

leaving out the problem of the drop in FPS after a few seconds with the radar on, this is another problem.

I attach video track before and after the update a few days ago. In addition I attach the track of the tacview and the log.

before --> video made on a public server, using radar (at minute 0:48 - 04:00 - 07:25). It worked perfectly. : https://youtu.be/eRiq0kVfo1Y
after --> : https://youtu.be/USkUiTGKtrw

any updates?
I saw that the highlighted problem was not assigned.
Especially in public servers against other players, this is a big problem, we can only fire IR missiles.

Problem seems related to altitude/ground clutter? I've noticed the radar works fairly consistently if clutter is not on scope (ie if altitude >5km), but below that, it will either see nothing or it will only see things that are <5km off the nose.

yes I did a test: Low / medium altitude enemy planes are not seen, at high altitude yes. soon the two videos.

here are the two tests

low/medium altitude:
https://youtu.be/USkUiTGKtrw

high altitude:
https://youtu.be/3N4kQs1AxBE

I'll have to set up a mission to get a 'clean' trackfile from, rather than a long one with the bug several hours into a mission, but I do have a clip demonstrating this behaviour as it happened during a MP session: https://clips.twitch.tv/EnchantingBlueOrangeUncleNox

I've encountered this several times now. At first I thought it was coincidence but it is very reproducible. When pursuing a target, it will not render on the scope at all until it passes into the clutter band - if ground clutter is in view. At altitudes where no clutter is rendered the radar still appears to function normally. I cannot confirm for sure that the behaviour also happens with closing targets, but this is probably because the closure rate is too high and so by the time the target enters the clutter band it is just about to pass out of the radar's view anyway. The problem exists in both SP and MP scenarios.

In terms of severity, this makes any form of radar-assisted engagement impossible below about 5-8km altitude and makes R-3R use below these altitudes impossible.

Please re-check and submit tracks with the latest open beta update.

The fps drop is gone. You see your contacts, but you can't keep them hooked well. If there are mountains or terrain behind the enemy, the lock is immediately lost.

@OBERST78 The performance of Mig-21 radar was modeled quite accurately IMHO. The situation you recorded on low/medium altitude video (https://youtu.be/USkUiTGKtrw) is actually reflecting the behavior of early radar systems. Early doper radars cannot differentiate between ground and plane echo if the target is below horizon line (which is most of the time on your video). Also on low altitude the side bands from antenna are reflecting from ground and radar will have hard time to get the lock if you are not pointing your nose above the horizon line.

Also remember this is radar from late 50s, not the one in F16 as you seems to make rolls in hope to lock the target in beam mode.
The radar only have 20deg in azimuth and in scan mode and couple of deg in elevation in beam mode, so you really have to point your nose on the target in order to lock it (rolling will not help).

I'm talking about how it worked before and how it works now, I'm not talking about radar as it must be in reality. If you had flown the mig21 before, you would have noticed the change, as have other pilots. The problem has also been recognized by the developers, maybe they will know a little more, since they have read manuals and manuals.

the radar in the map of Syria still gives problems of FPS drops.
after 3 seconds, the FPS drops begin. just have contacts in front and you feel the drop in FPS.
@Roland