for kkvs use a meter of boron needle like slope and cross your fingers because if your point defense didnt work you are sooooo screwed. armor does help against wider flak patterns but focused missile fire will melt anything - redundancy is your friend.
the bigest mostest fastest! it is a bit hard to make flak with enough spread to spread damage evenly yet have enough speed and mass to do damage defeat armor. im thinking of starting to use guns with low velocity on drone kkvs that way they can target modules or just land more of the payload on target. not sure if its worth the mass though. dang it i need proper missile targeting. literal no reason not to use laser guidance or some sort of remote control and steer missiles with the main ships targeting gear.
Theory states: The outer layer of wipple shield should be thick enough to fracture the projectile and spread it out to allow a larger area (via gap) of armor underneath to absorb the explosion of plasma and hypervelocity fragments.
In practice ingame: more graphite aerogel (several meters thick), adjust top and lower armor to be effective for their weight/cost against expected incoming threats (including laser if relevant)
Graphite aerogel is awful against lasers, though. Well, I did most of my laser/armor testing prior to 1.08, so if this has changed please let me know.
You also need vast volumes of it, greatly increasing your cross section compared to conventional whipple shields, nevermind unspaced armor.
vs Kinetic Sand the amimai composition (Diamond-topped armor with a high strength (usually Carbon/Boron) backing and spall liners behind it) seems to be the best; and vs heavy kill vehicles (whether nuclear penetrator, frag/flak or pure kinetic rod) no practical amount of armor seems to make a difference.
I forgot to mention, he's asking for the impossible.
Well, I kinda figured, but I was curious if others had better solutions. Turns out they do.
i.imgur.com/Ql038Et.jpg Amimai's armor at double thickness. Some surface melt, but no internal damage. However, this is with fragmented impactors optimized against lighter armor. If I remove the frag charge it'll go through. Still, a much, much better result than what I managed.
On the note of fragmenting vs non-fragmenting kinetics, unless your target has insane armor you really want it to fragment. Just add a small explosive charge (don't need a shrapnel shell, it seems the missile itself fragmenting works fine), and the difference looks like this: Pure KKVs: i.imgur.com/qizqyp6.jpg Fragmenting KKVs: i.imgur.com/XmHPhfR.jpg
The problem with armouring against KE is players only really design two types of KE threats.
One is KKV/NEFP which tend to be too big and too fast to reasonably armour against, on the plus side these are reasonably large and move at a reasonably slow speed (i.e. nearly negligible compared to C) so they can be defeated by point defences and evasive manoeuvres, maybe decoyed by flares. Basically passive armour is never going to be cost- and mass-effective against them compared to active defences.
The other is sand/needles which, due to the way rail/coilguns are designed currently (rate of fire not dependent on main weapon energy input), can simply be launched in far too great numbers to be realistically stopped by practical armour. You can definitely stop one needle, you can probably stop ten needles hitting the same armour tile, but right now needleguns just have too high a rate of fire and your armour will fail due to cumulative impacts. Althouh the KE sandstorm only moves at a few percentage points of C, while lasers hit at C, so the solution to needlegun boats seems to be outranging them with lasers.
Armour may be viable as a last line of defence against needlegun spray-and-pray at 1Mm provided it is both strong and compact, and the attacker is rapidly destroyed so you don't have too many impacts.
Actually I now use 10g+ coilguns or 70km+ railguns so wipple armour is a horrible idea, the rounds I shoot cut through soft wipples like paper... hard surface layers are useful since they can bounce off most kinetic rounds