Some more musings from me about attacking SAM's..... This is purely my own thoughts from what I have found works and does not work, and certainly not official procedure, as that's all classified anyway, lol. Your mileage may vary.
Different SAM's require attacking at different heights, as they have different engagement ranges. Think of it as a dome of different sizes above the launcher depending what it is. To destroy a SAM you have to encourage it to turn on its radar and track you, so you can in turn track its radar. Its no good flying at 30,000 ft above an SA 8 or SA 15 as you are out of its engagement range, so it won't turn on its radar, and you won't know its there.
Below is a pic I've channelled my inner Leonardo da Vinci to make, it will do the job though hopefully!
The worst place to be attacking a SAM from my experience and watching others, is to enter the SAM's max range near the top of its engagement range, as you will suddenly find a missile coming at you with very little options of what you can do, since any direction you dive to attempt to notch, you are further entering the SAM's area of engagement. You stumble into a very fast missile SAM like a SA-15, you are pretty much dead, unless you are incredibly lucky and can climb out of its range quick enough (you won't).
Coming in at a low height, while nowhere near as deadly to yourself, as you have plenty of distance to turn away and can terrain mask, but is not particularly effective as your own HARM's will have a much shorter range due to the thickness of air down low, so your missiles will have no where near as much energy which makes them much more susceptible to being intercepted by SAM's that can self protect shoot. Also being low you can run into other nasties laying in wait for you like manpads and AAA
Also and probably more important, HARM's fired from lower altitudes do not come into the target anywhere near as vertically as those lofted from higher altitudes. This often results in misses that do no damage as a flatter trajectory going just over the SAM will not impact the ground for much more distance than one coming down near vertically just missing the emitter.
This leads to my optimal attack altitude, around half way up the SAM's engagement range. It gives you plenty of options, and you can skirt around it tempting the SAM with only a 90 degree turn to head away, and can dive away and notch to. You are clear of manpads and most AAA, and your HARM will comedown with plenty of energy and at a fairly steep angle.
Of course, knowing what SAM's you are going against helps.....
But as a rule of thumb, for SA-8's SA-15's I find around 15,000 ft works very well, SA-6, SA-2, SA-11, 20,000-25,000 ft works well, and going up against an SA-10 30,000 ft plus.
Going in at 15,000ft into unknown SAM territories gives you good scope to find what's there and be able to respond accordingly.
Hope this helps 👍