How is "armor manufacturing flaws" modelled?

[Skwabie]

Right... haven't bought CMBN yet so just reading the game manual on the site.

On the wiki page there's description on Panther G early:

"Glacis armor has occasional maneufacturing flaws"

and Tiger I late:

"many armor plates have a lower standard of 'hardness' due to production shortcuts"

I'm just wondering how does the game model this feature? Is it by applying some random coefficient to the armor thickness when a shell impacts?

[John Kettler]

Skwabie,

I believe the answer is that the effective armor thickness is reduced in such cases. There may (note conditional) be some sort of under the hood "die roll" to see whether a given tank has such a manufacturing flaw or plate hardness issue. If you're interested in the armor quality issue per se, and not just for the Germans, may I suggest the below thread in which a bunch of armor grogs, including our own Robert Livingston (co-author of World War II Armor and Ballistics), hash out the issues?

http://www.battlefront.com/community/showthread.php?t=110208

Regards,

John Kettler

[MikeyD]

On several occasions they've stated that this Sherman was assigned moderate quality plate, that other tank was prone to spalling. There's a lot going on under the hood that they don't tell us about. I'd imagine armor quality would be an even greater factor when we're talking late war German tanks versus Russian T34s.

[Skwabie]

..

Thnx for the link John i'll give it a read. Also gonna give the bird livingston book a go, looks like a bible around here.

On several occasions they've stated that this Sherman was assigned moderate quality plate, that other tank was prone to spalling. There's a lot going on under the hood that they don't tell us about. I'd imagine armor quality would be an even greater factor when we're talking late war German tanks versus Russian T34s.

after searching the forum I too wish there's more info on how the game models these things, atm there's almost none... take a leap of faith huh

[Bil Hardenberger]

This post also has a discussion from Charles himself on how armor works in the game. Though it doesn't discuss your topic directly I think there are some very good snippets of information that can help you understand how CM handles it. The game does take armor quality into account.

http://www.battlefront.com/community/showpost.php?p=1239443&postcount=303

[phil stanbridge]

I remember in cmx1 there was a details panel you could bring up which told you exactly that.

[c3k]

If you're serious about searching for a product with the best ballistic simulations available on the market, you won't find anything that beats BFC's games. It may be a leap of faith, but the demos are free to download and use.

You, the player, don't get armor quality information. Why? Well, did Hans or Rolf know whether or not the glacis plate of their Panther was quenched properly? That information is under the hood.

Now, how is it used? I don't know. Do all late Panthers have the SAME exact armor levels? Or, are some "golden samples" and others are nerfed? I don't know.

Reading between the lines of many postings, I'd hazard a -guess- that all tanks of the same model are treated as being armored identically. However, that doesn't mean that they'll act the same with the same type of hit. I think there is a bit of deviation built into the game to model slight differences. A bit of a bell-curve. I don't know.

Good question...

Ken

[Skwabie]

so I did a test...

Scenario 1, a M4A3(76W) 150 meters from a Tiger I Mid, both head to head.

Scenario 2 same as 1, except changed the Tiger I Mid to Late.

Both Scenarios ran 20 times. In scenario 1 it took average of 4.35 shots of the sherman to knock out the Tiger I Mid. In scenario 2 it took average of 4.9 shots to knock out the Tiger I Late. As the manual states, Tiger Late has lower armor quality, so ... what gives??...

[John Kettler]

Skwabie,

What I think may be happening is that the hardness of the second Tiger I model's plate may be lower, which in turn makes the armor tougher (more like homogeneous armor on the Sherman) vs 76mm APC, which, as you'll see in the M10 ammo thread in CMFI, is far more effective against German face-hardened armor than was the earlier fielded 76mm AP, which was Shot, rather than APC, which was shell.

I shall be most interested to see what our terminal effectiveness types have to say on this worthwhile observation by you. Naturally, the testers among us will want incredible levels of detail regarding your testing area, crew morale, fatigue status, spotting status, buttoned or unbuttoned, temperature, phase of the Moon, presence or absence of "Dear Hans" letters and other useful minutiae!

Regards,

John Kettler

[Vanir Ausf B]

Both Scenarios ran 20 times. In scenario 1 it took average of 4.35 shots of the sherman to knock out the Tiger I Mid. In scenario 2 it took average of 4.9 shots to knock out the Tiger I Late. As the manual states, Tiger Late has lower armor quality, so ... what gives??...

That's about a 12-13% difference. That could be the flaw showing up or it could be random variation. We would need more information, such as range, total number of hits, how many penetrated, what type of penetration, ect.

From Charles's comments CMx2 seems to model flawed armor as a % decrease in effective resistance. We don't know what the % decrease used for the Tiger is, but 10-15% would be similar to other tanks with known armor flaws such as the early Sherman and late Panther.

[Vanir Ausf B]

What I think may be happening is that the hardness of the second Tiger I model's plate may be lower, which in turn makes the armor tougher (more like homogeneous armor on the Sherman) vs 76mm APC, which, as you'll see in the M10 ammo thread in CMFI, is far more effective against German face-hardened armor than was the earlier fielded 76mm AP, which was Shot, rather than APC, which was shell.

Tiger I armor is rolled homogeneous.

[John Kettler]

Vanir Ausf B,

Tiger I armor was indeed rolled (oops!), but from the exceedingly groggy metallurgical-military discussion here, the metallurgy was considerably more complex than that simple description you provided suggests. Indeed, the Germans started as early as 1931 making RHA of a type considerably different than ours and shifted that approach considerably during the war.

http://kbismarck.org/forum/viewtopic.php?f=13&t=80

A most informative read--provided your head doesn't explode!

Regards,

John Kettler

[Skwabie]

That's about a 12-13% difference. That could be the flaw showing up or it could be random variation.

uhmmm.... manual says Tiger Late armor is flawed. in my test, it takes more shots to knock it out than Tiger Mid. atm, I chalk it up to randomness. probably need to run it a few more times to even that out...

[Vanir Ausf B]

You're right, I misread your post.

To really test this you need to test a specific plate on both Tiger I models at a range where about 50% of hits would be expected to penetrate. The driver plate -- called the "superstructure front hull" in-game -- would work well for this at 500 meters against US 76mm APCBC.

[Oddball_E8]

If you're serious about searching for a product with the best ballistic simulations available on the market, you won't find anything that beats BFC's games. It may be a leap of faith, but the demos are free to download and use.

You, the player, don't get armor quality information. Why? Well, did Hans or Rolf know whether or not the glacis plate of their Panther was quenched properly? That information is under the hood.

Now, how is it used? I don't know. Do all late Panthers have the SAME exact armor levels? Or, are some "golden samples" and others are nerfed? I don't know.

Reading between the lines of many postings, I'd hazard a -guess- that all tanks of the same model are treated as being armored identically. However, that doesn't mean that they'll act the same with the same type of hit. I think there is a bit of deviation built into the game to model slight differences. A bit of a bell-curve. I don't know.

Good question...

Ken

I don't think he is asking for that information to be in the game during a battle, he is just asking how it is (or if it is) handled under the hood.

There are alot of "under the hood" things that are never mentioned in the manual.

And I for one think it would be a good addition to have in the manual so that grogs know that it is simulated in the game.

[Michael Emrys]

probably need to run it a few more times to even that out...

Yes. There is enough variability built into the code that to be really confident of your numbers, something like a hundred iterations may be needed before a true trend starts to show up. At least that has been the experience of a number of testers over the years.

Michael

[PanzerMiller]

Yes. There is enough variability built into the code that to be really confident of your numbers, something like a hundred iterations may be needed before a true trend starts to show up. At least that has been the experience of a number of testers over the years.

Ya beat me to it, Michael...yes, an absolute minimum of 100 iterations would be necessary to confidently detect true differences in behavior, based on statistical arguments. The occasional odd outcome, often spawning a "fix it or do somefink!!" response, is not what we're concerned with here.

[Michael Emrys]

Just to drive this point home, a few years back a poster decided to do a marathon test on some controversial bit of behavior in the game. During the first hundred iterations it appeared that a trend in one direction was indicated. But after that the numbers began to flow in the opposite direction and by the time he had hit a thousand, which was his goal, the clear trend was opposite to what it had been at the start. So this kind of test can require a lot of careful work.

Of course, you can always say, "Hey, it's just a game!" and take it as it is, however it is.

Michael

[Skwabie]

Agreed with above... I did 40 more runs and the numbers vary too much. At one time the sherman ran out of AP ammo and the tiger still wouldn't go down. That's 30+ shots.. Meanwhile there're many times when one hit was enough.

the "superstructure front hull" in-game -- would work well for this at 500 meters against US 76mm APCBC.

Much better idea indeed... Is there a terrain feature that could cover up the turret and the lower hulls and still allow the tank to be shot at... Can't seem to find one atm..

[Oddball_E8]

Agreed with above... I did 40 more runs and the numbers vary too much. At one time the sherman ran out of AP ammo and the tiger still wouldn't go down. That's 30+ shots.. Meanwhile there're many times when one hit was enough.

Much better idea indeed... Is there a terrain feature that could cover up the turret and the lower hulls and still allow the tank to be shot at... Can't seem to find one atm..

Bridge with a higher ground behind it?

It would take ALOT of fiddling around with the editor, but should be possible...

[Vanir Ausf B]

Much better idea indeed... Is there a terrain feature that could cover up the turret and the lower hulls and still allow the tank to be shot at... Can't seem to find one atm..

Yes. You just raise the ground in front of the tank by 1 meter to create a berm. I may go ahead and run this test later tonight since I already did it for the Tiger mid when testing shatter gap. I just have to swap in Tiger lates and run it again.

[Vanir Ausf B]

Testing done. Here is the results from my shatter gap testing done on Tiger I mid

Sherman76 vs Tiger mid at 500m and 10° horizontal offset

Hits on driver plate: 105

No damage: 6 (6%)

Spalling: 47 (45%)

Partial Penetration: 50 (48%)

Penetration: 2 (2%)

And here are the results of the test I just did which was identical except for the Tigers were late models:

Sherman76 vs Tiger late at 500m and 10° horizontal offset

Hits on driver plate: 146

No damage: 11 (8%)

Spalling: 45 (31%)

Partial Penetration: 83 (57%)

Full Penetration: 7 (5%)

Not a dramatic difference, but a significant one, which is about what I would expect.

[Skwabie]

Hi VAB, can you share the scenario? I think it would save me sometime fumbling with scenario editor...

Did some few more runs on me own with weird discoveries. Yesterday ran each 50 times for tiger Late and Mid. But for these 100 runs the tigers were without crew:

50 Tiger Late destroyed, 122 shots fired at, average shots for destroy 2.44

50 Tiger Mid destroyed, 162 shots fired at, average shots for destroy 3.24

And, more tests ran, with crew:

53 Tiger Late destroyed, 279 shots fired at, average shots for destroy 5.26

53 Tiger Mid destroyed, 234 shots fired at, average shots for destroy 4.42

So the tigers without crew are much more fragile. Is vehicle damage modeling without crews simplified?

Also while a Tiger Mid without crew is tougher, it's the other way around with crew. What gives..

There have been 3 instances (among 53 total) where the Tiger Late withstood 20+ shots and still wouldn't go down. One case the sherman ran outta AP ammo with the Tiger Late still standing. I had to discard that result because well there's no longer a shot count.

Is the Tiger late crew better at damage control (or is there such a thing in game) or is the random factor still playing.. More tests to follow I guess...

[Vanir Ausf B]

Scenario and save game:

https://www.dropbox.com/sh/eb29rftquo7e84o/6q36x_hLD7

The Tigers are slightly offset in this test to match the parameters of my earlier shatter gap test, which I did not want to repeat.

[Skwabie]

Thanks mate! I'll try something similar as apparently 1 tank per run ain't very efficient.