The backing plate isn’t what catches spall, though. The stuff before the plate (that is within the NERA) is what reduces spall generation.
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It still has to maintain them so may need to know how to perform basic repair, recovery, and maintenance functions. That likely would include painting them on top of being able to weld plates for their minor modifications made after they were supplied and that would need at least some oversight of the standards to be able for it to be certified(however minor).
MIL -A -46099C , MILITARY SPECIFICATION: ARMOR PLATE, STEEL, ROLL-BONDED, DNAL HARDNESS (0.187 INCHES TO 0.700 INCHES INCLUSIVE (14 SEP 1987)
Sure, but standards tend to be updated frequently with best practices and errata without significant changes to the content, and version control and revisions can be difficult to keep track of even for relatively straight forward documents.
and what we know of the M1A1 (and modified Turret / hull used on the CATTAB ) elements have varying thicknesses, and so may be of mixed composition instead of uniform across all structural elements.
It doesn’t catch spall nor does the “reduced spall generation” matter because… it itself spalls.
Jesus. I mean it’s already been said multiple times but the way you ignore reality is truly something else.
Personally, I couldn’t do it.
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Sites such as that only state what isn’t ->Classified to the Public. Do understand that the Public only knows so much from what is legally deemed allowed. However, if a vehicle is getting heavy it isn’t electronics. Those sure make something heavier however their not going to make the hull fat in terms of weight.
No, that is not what happens. The backing plate is not the thing absorbing the shock waves (and therefore suppressing spall generation), the liner before that is (visualization below).
The point of a spall liner like the one I’ve been talking about is to make sure that whatever is behind the liner can withstand the shock wave forces and therefore not spall.
I have shown sources where they literally experiment with this idea and find that it works.
I should be the one telling you that you cannot just ignore how reality works.
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That is correct, but they don’t need to know the specifics of its steel - such information isn’t needed for basic maintenence & repairing of insignificant damages.
MIL -A -46099C , MILITARY SPECIFICATION: ARMOR PLATE, STEEL, ROLL-BONDED, DNAL HARDNESS (0.187 INCHES TO 0.700 INCHES INCLUSIVE (14 SEP 1987)
Sure, but standards tend to be updated frequently with best practices and errata without significant changes to the content, and version control and revisions can be difficult to keep track of even for relatively straight forward documents.
“This specification covers roll-bonded, dual hardness, steel armor plate for lightweight armor applications” - doesn’t sound like something you’d use in the M1.
and what we know of the M1A1 (and modified Turret / hull used on the CATTAB ) elements have varying thicknesses, and so may be of mixed composition instead of uniform across all structural elements.
Right, but you’re just reaching for favourable conclusions based on a document not relevant to the M1 Abrams. @Necrons31467 has already shown that CATTAB, despite having “varying thicknesses”, employed actual spall liners for crew protection.
To add to that, the Aussie report is about armoured steel that ranges from ~500 - 560 HB at the front and ~340 - 370 HB at the back (or more). That is not ductile steel that would be preferred in such instances, it will still spall just as much as any other steel within this hardness range (hence why in the report they state; "Electroslag remelting (ESR) (refer Section 8.2) was used to produce dual hardness armour with front and rear face hardnesses (500-560HB front, 340-370HB rear) better optimised for improved fragmentation protection [57].") - just less than the harder, front-facing plates normally would. This can not work as well as an actual spall liner under any circumstances, and I’ve no idea why you’re trying to argue this point even.
Yes… The reality where ~20-40mm of RHA doesn’t spall because the shell went through a spall liner beforehand, because…? Magic. And also text walls that mean nothing to Gaijin, or to anyone trying to model the Abrams, because they’re not actual sources.
I guess in that reality - early tanks with lighter armor also didn’t spall, since the only thing stopping the spalling from a fully penetrating shell in your “representation” is the backing plate simply being thin.
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Its because spall generation requires enough energy through failure by shear forces caused by the shock wave, but fracture failure from the penetrator/jet can still occur under that energy threshold. I already showed sources that went over this:
Nah let make things clear again. I’m talking solely about Integrated Spall Liner.
not about whatever Abrams has spall liner or not.
As i said -There are no disclosure about Abrams internal spall liners “yet” .
What are you on about ?
You do realize that in order for shell to complete penetration. It has to go through armor first ? those picture are showing difference armor failure while the shell go through it. It is a part of what we are talking about.
And i would said it again. If the last layer are not RHA and backplate itself are ductile enough. it would barely create any spall by itself. that one way to put it.
As for Abrams Integrated Spall Liner. refer to SpeclistMain.
When is the backplate “ductile enough”? How does it perform relative to proper spall-liners? Why would the Army & the manufacturer make sacrifices in actual protection to lower the amount of spall fragments (which can be reduced via an addition of wall mounted spall liners either way).
I mean, you’re claiming “it would barely create any spall by itself”, but what is that claim based on? I’ve read through the Aussie doc and there’s nothing on the spall spread (cone) and the amount of fragments.
Turns out Australia acquired a bit more than I thought.
Also included is development of a unique armor package, Common Remotely Operated Weapon Station Low Profile (CROWS-LP), Driver’s Vision Enhancer, mission equipment, special tools and test equipment, ground support equipment, system and engine spare parts, technical data, publications, Modification Work Orders/Engineering Change Proposals (MWO/ECPs), U.S. Government and contractor technical and logistics assistance, quality assurance teams, transportation services, program management, New Equipment Training (NET); and other related elements of logistical and program support.
It would be if you were trying to save weight at all costs to allow for the recovered mass to be used to improve performance elsewhere, you know how the M1 is pretty well acknowledged to be pretty heavy, and part of the purpose of the various modernization initiatives was weight reduction / redistribution.
It was a technology demonstrator, it’s going to as efficient as it can be with project funds so will investigate as much as possible, and considering that it was part of upgunning an existing tank to prepare it for combat against potentially 155mm guns its probably a good idea to try and save weight if possible.
There are many ways to produce improved survivability M1s in game, considering that ESR isn’t its own material (I think that it’s implemented as structural steel in the protection model) that could have its own adjusted RHAe & (reduced) spall modifier in comparison to RHA, considering we probably have enough data to approximate it.
If anything it probably points to the abstracted performance of Spall liners as they are slightly overperforming.
I personally doubt that the back plate would be ductile enough, but the idea of absorbing the shock wave enough to reduce or eliminate spalling from an RHA back plate is something that has been tested and shown to work (the absorbing liner is before the back plate btw). Check my message here:
Here one more about M1 BREACHER which clearly mention spall liner in its list. using Abrams chassis
Program for the Army got cancle while the USMC program kept going. which currently is M1150.
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It’s not a website, it’s a document: ‘‘RD&E Center Finite Element Stress Analysis for CATTB’’ https://apps.dtic.mil/sti/tr/pdf/ADA228389.pdf
Also, the point is that some users implied spall liners are inherently classified, that clearly isn’t the case from this example (and the one CodeNameColdWar mentioned above).
It is.
TheChieftain estimates several tons of weight can be attributed to the wiring inside an M1.
Its more that if it was integrated into the Armor array its going to be classified, since the actual composition is obviously controlled information.
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Not really relevant to the topic at hand but cool to know.
It would be if you were trying to save weight at all costs to allow for the recovered mass to be used to improve performance elsewhere, you know how the M1 is pretty well acknowledged to be pretty heavy, and part of the purpose of the various modernization initiatives was weight reduction / redistribution.
Yes, sadly that’s a close-ended point because US went the Titanium route in order to reduce the weight of M1s starting from the M1A2 SEPv1:
https://www.tms.org/pubs/journals/jom/9705/montgomery-9705.html
There are many ways to produce improved survivability M1s in game, considering that ESR isn’t its own material (I think that it’s implemented as structural steel in the protection model) that could have its own adjusted RHAe & (reduced) spall modifier in comparison to RHA, considering we probably have enough data to approximate it.
How does this “steel” perform relative to other nations steels, again? Nothing posted in this thread so far indicates that it would outperform steels of comparable hardness when it comes to fragmentation upon a perforation, everything’s that been stated about the “dual-hardness plate” is that due to the back-end having a lower hardness makes it better optimised for fragmentation protection relative to the front-end portion of the plate.
If anything it probably points to the abstracted performance of Spall liners as they are slightly overperforming.
You are free to present data on this (atm they’re underperforming in fact…).
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Hey - that’s perfect. It literally states the M1A2 doesn’t have a spall liner.
So all that “integrated spall liner” nonsense was just… nonsense. Great.
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I’ll add to that, here’s the steels used in German AFVs;
They’re of comparable hardness, so, following the train of thought that people are pushing forward here, can I say they shouldn’t spall at all too? Especially the 2A7V since it makes use of lower hardness steels for its backplates + has actual spall liners on top of that. Or is this a case of “for me, but not for you”?
How many T-90M’s have been blown up at this point? So it should be fairly obvious that it doesn’t
stop everything I know there was a relevant presentation slides for the Bradley’s liners around somewhere.
It also wrong about the M60 not having a liner either… considering it also references a laser range finder and M21 Ballistic computer is referencing the M60A3 RISE or -TTS configuration which have Kevlar turret liners.
I’m 101% positive this has to do T-90Ms ammunition placement (what good will spall liners do if the KEP or the CE jet are heading straight for the carousel, again?). But, if that makes you feel better, you can keep believing that T-90Ms exploding to direct ammunition hits prove that spall liners do not work (technically speaking, that makes it a logical fallacy but i’m not sure which one yet).
Spall liners in the game don’t stop everything like you state (they’ve went through nerfs ever since their addition), have you checked them out recently, honestly speaking? Cause T-90Ms & 2A7Vs liners basically don’t function anymore, their spall cones are comparable to those found in vehicles without spall liners (>90°).