We always include air for armour, for both russia where it is specified and nato where it is nera.
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It’d be nice if we knew how much air to plate ratio was, and what plate hardness they chose.
this is all simplified through use of a KE modifier
iirc thats one of the (many) modelling advantages for the Russian tanks. instead of being modelled as a single “composite array” with a set modifier defined by gaijin, the UFP on Russian tanks is modelled as a multi plate system with each plate getting a positive modifier to account for the filler layers between them, which is how the Russian UFP end up with a positive KE modifier on their composite UFP while all NATO composites end up with a negative modifier.
I also have a sneaking suspicion that due to modelling, having more individual armor entities for a shell to go through leads to more chances of the armor “eating” the shell.
As with many things in this game, gaijins modelling “choices” disadvantage western tech and substantially buffs Russian tech, such as things like not modelling regenerative steering leading to NATO tanks being substantially less nimble than they should be, armor shenanigans, etc…
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Leopard 2
Turret Composite is 750mm thick, from the front the angle is 30-35 degrees giving 860mm LOS
Hull composite is 750mm thick
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Except it’s not actually 750mm thick.
Cause there’s a ton of air between all the plates.
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Just like on russian tanks… thats the whole point of composite KE modifiers.
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You’re missing the point I think, Sombralix is talking about how the effective protection of the T72B is far more than 530mm. The 530mm figure given in documentation means that a KE penetrator needs to get through 530mm LOS of RHA at 68 degrees in order to penetrate the T72B. It does not mean that a longrod monobloc KEP needs 530mm flat penetration to go through, as that would require the round has far more than 600mm of LOS penetration at 68 degrees.
We know it’s this way round for a few reasons:
- Protection figures never mention a specific round, different KEP designs behave differently at angles and a flat penetration figure would be useless without specification of the round it is against. Furthermore, the Soviets hadn’t fielded a monobloc longrod penetrator yet so it makes no sense they’d use the flat penetration of one as the reference
- Conversely, penetration figures are always given in LOS thickness. L23A1 is stated as having 490mm pen in documentation but this is the LOS penetration at 68 degrees. The same is the case with L26 documentation as well as 3BM59/60
So with this we know that a 530mm vs KE figure should equate to:
530*cos(68) = 198.5mm at 68 degrees. Any KE shell that can go through more than 198mm normal thickness (aka if the angle was 0) of armor at 68 degrees has 530mm LOS penetration at 68 degrees and should go through the T72B. In game shells with 220mm or more at 68 degrees go through, meaning the T72B’s armor is actually 590mm RHAe LOS instead.
The tank is overperforming and OP is correct, it’s a universal problem with the way Gaijin has done tank protection that has disproportionately benefitted USSR top tier. Haven’t exactly explained this brilliantly and have skimmed the thread a bit but oh well.
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Except I showed an image of the T-72B being 514mm equivalent with the round going through ERA.
Flat equivalent pen cannot be used to prove angular penetration equivalent.
How is the tank overperforming & OP if the armor is only 514mm effective firing through Contact 1 LOS 65 degrees?
Fun fact, it’s ~530mm equivalent when firing avoiding ERA LOS 68 degrees.
Image of that BTW:
Where have you shown this. It’s objectively incorrect considering when firing into the UFP at 0 degree angle you get a 220mm value vs KE, which is 590mm LOS equivalent.
Flat penetration is entirely useable to get angled LOS effective thickness if you’re looking at a 0 degree impact angle in the protection analysis.
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Earlier in the thread, and the ~530mm one just now.
The key word you said: 0 degrees.
The zero degree angle of armor equivalent cannot be used to prove the angular armor thickness nor equivalent.
And that’s what we’ve proved here.
Edit:
I have a proof for something: Earlier I posted Ariete, 142mm equivalent with 114mm of equated armor zero degrees.
At 64 degrees, the penetration equivalent is 271, or 271*cos(64)=118.
Abrams: 342 eqiv @ 0deg.
608*cos(59)=313.
Soviet’s aren’t the only ones with 0 degree armor having a higher number than angled penetration multiplied by cosine.
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Abrams: 342 eqiv @ 0deg.
608*cos(59)=313.
As far as I can see, you have no idea what you’re talking about. @Sombralix explained the problem very well, and @UKoctane basically did a ELI5 for you… yet you’re still missing the point?
To make it as simple as it is humanly possible; T-72B was nearly penetrated by 3BM-32 Vant in real life, that round is around the performence level of DM23 used by the Leopard 2A4 but for some reason projectiles such as DM33 and M900 which are, on average ~20% more powerful cannot defeat the armour of this tank?
What is your “calculation” even meant to represent exactly? The hull? The turret? The turret sides?
All your examples scream of “I talk a lot without saying anything”.
I’ll just wait and see what you make out of it.
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I think you’re misinterpreting the figure shown by the protection analysis here, looking at the angled values will always be misleading from LOS due to the differing slope modifiers of various shells, it will only scale with LOS for HEAT shells since they have no positive or negative normalisation and only penetrate the exact LOS path length. The value in game is saying “This shell with it’s slope modifiers would need this much flat penetration to get through this armour”, it is not at all a comment on exact LOS thickness due to different slope modifiers. In your Ariete example, 142mm of protection has been turned to 271mm or 118 LOS thanks to the positive normalisation of modern APFSDS, it penetrates more LOS thickness at angles than flat.
When looking at the 0 degree angle, no matter the KE shell, the thickness displayed will be the same. That is objectively the equivalent thickness of that array if it was displayed to a target at a 0 degree angle. It is also the amount of raw penetration needed at the armor’s actual angle to go through, which gives the true LOS protection of that armour, e.g for the Ariete it’s 142mm@60 or 284mm LOS thickness. Any shell with more than 142mm@60 has more than 284mm LOS penetration at that angle and can get through. I’m presuming this part is indisputable since it’s basically common sense and proveable in game. So when the T72B in game offers 220mm flat, it has 590mm LOS protection at 68 degrees. If you took a KE shell with perfectly neutral normalisation (i.e penetrates say 500mm at 0 degrees, 250mm at 60 degrees, 187mm at 68 degrees etc) then the protection analysis would say the equivalent protection against the specified ammo is 590mm.
TL:DR you can’t use shells with positive/negative normalisation to talk about LOS protection. You HAVE to use the 0 degree protection and then calculate it with trig or you’ll get Gaijined.
tbf am pretty tired and drifting all over the place here but I hope you get the point.
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You’re intentionally misleading yourself then.
You also ignore the fact that I proved this occurs on ALL tanks, not just Soviet tanks.
@FurinaBestArchon
BTW I found no testing report involving T-72B & Vant.
Partial penetration does not prove too much either.
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Just to add to this
This is the Penetration of 125mm 3BM32 ‘Vant’ APFSDS
380mm long DU penetrator that weighs around ~4.3kg
Muzzle Velocity is 1710m/s
Penetration:
422mm @ 0m at 0 degrees
197mm @ 0m at 68 degrees - 526mm LOS
APFSDS with only just above 420mm of vertical penetration nearly penetrated T-72B hull with the 1989 array without Kontakt-5. Yet in game we need 530mm at 0 degrees with APFSDS to penetrate T-72B hull.
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Double posting oh well but I’m going to use pretty pictures here using our good old faithful the T34 to explain why the protection analysis number is ONLY trustworthy when looking at LOS at either 0 degrees or when using HEAT.
As well all know the T34’s hull is 45mm at 60 degrees. I think we can all agree that this is 90mm LOS thickness (45/cos60).
Going to use 2 shells, 3BM42 which has positive normalisation, and 3BM22 that has negative (3BM42 penetrates more LOS the higher the angle gets whilst 3BM22 penetrates less)
When striking the hull with no angle, both say 45mm, but when striking at the 60 degree angle:
You can see that 3BM42 says less than LOS, and 3BM32 says more, due to 3BM32 penetrating less LOS thickness at 60 degrees than it does flat, and 3BM42 penetrating more. Does this mean the LOS thickness of the T34’s armor isn’t 90mm though? Absolutely not, it’s just Gaijin’s way of easily displaying how close you are to getting through armor with a certain shell, but can be misleading when trying to work out LOS values.
Here’s HEAT with perfectly neutral normalisation and the exact LOS thickness:
I’m not intentionally misleading myself I’m just objectively correct, I know it sounds cocky but it’s true and I really hope the explanation above helps. Yes it affects tanks other than the Soviets too, some benefit, some suffer, but the Soviets disproportionately benefit due to their high armor slopes and the use of longrod rounds as the reference flat penetration instead of LOS thickness.
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Just because you haven’t found something doesn’t mean it didn’t happen. I could share it, but what’s the fun with just serving you something on a silver platter?
As for you “proving”, well, UKoctane just disproved it lol. Ironically he did what I wanted to do, so well, that spared me a few minutes.
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3BM-22 doesnt actually have negative normalisation its just that the carbide core tip inflates its vertical penetration at low obliquities. without the carbide core, the shell slope modifier would look exactly the same as other APFSDS.
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Well you learn something new everyday (like whacky Soviet APFSDS designs), but for the purpose of what we’re trying to prove here it gives the same result.
Right, I’m off to bed
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