Naval Guns: Penetration vs Anti-Armor

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Admiral DadMan
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Naval Guns: Penetration vs Anti-Armor

Post by Admiral DadMan »

Are they interrelated? Interchangeable? Is one irrelevant?

I know that once JWE/Simon described how range can affect strike angle and penetration in relation to a belt or deck hit. What I'm trying to get at is how to accurately reflect it in gun stats in a mod so as to do it properly and not unnecessarily overthink it.

Also, I've been trying to figure out where the naval gun pen values were got from. I can't seem to sort out how Nathan Okun's numbers were used in the game.
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witpqs
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RE: Naval Guns: Penetration vs Anti-Armor

Post by witpqs »

John did go into that as I recall. Don't have a link for you but I know it's there.
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RE: Naval Guns: Penetration vs Anti-Armor

Post by Admiral DadMan »

Yeah I was hoping someone would remember, because it is eluding my advanced searching skills.
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cardas
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RE: Naval Guns: Penetration vs Anti-Armor

Post by cardas »

Aren't they just the penetration at 5000 yards from Facehard against US class 'A' armor?
el cid again
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RE: Naval Guns: Penetration vs Anti-Armor

Post by el cid again »

Presumably there is a chance of a hit on various things whose armor then is used.
Why have "conning tower armor" or "turret armor" if it can never be hit. Deck
I guess might be only used re bombs, but ideally it should also be used at long
ranges for guns. There are some indications this sometimes happens - what
might be called an HMS Hood effect. But it not clear how this is achieved.
It is likely to be semi-abstracted.
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RE: Naval Guns: Penetration vs Anti-Armor

Post by US87891 »

ORIGINAL: Admiral DadMan
Are they interrelated? Interchangeable? Is one irrelevant?

I know that once JWE/Simon described how range can affect strike angle and penetration in relation to a belt or deck hit. What I'm trying to get at is how to accurately reflect it in gun stats in a mod so as to do it properly and not unnecessarily overthink it.

Also, I've been trying to figure out where the naval gun pen values were got from. I can't seem to sort out how Nathan Okun's numbers were used in the game.
Not interrelated or interchangeable. Penetration is used in the Naval combat algorithm. Anti-armor is used in Land combat (bombardment, etc...). Anti-armor is typically 50% of Penetration.

Penetration is from Facehard and is a sort of "penetration at % of range" calculation. Something like 5" guns use Pen at 5K, 6" guns use Pen at 6K, 8" guns use 8K, 16" guns use Pen at 15K, basically align the classes of guns and make calculations uniform within a class. Facehard lets you get Pen against IJ armor, for Brit and US guns. Basically any kind of gun against any kid of armor. John has a program that spits out ballistics values that fit into Facehard, so we can model any kind of gun, anywhere. Cool things.
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RE: Naval Guns: Penetration vs Anti-Armor

Post by Dili »

"penetration at range % " is not what i am seeing in DaBigBabes, for example 15in/42 BL Mk I have 740mm, that kind of values are not possible at 14-15kyd.
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RE: Naval Guns: Penetration vs Anti-Armor

Post by spence »

Not interrelated or interchangeable. Penetration is used in the Naval combat algorithm. Anti-armor is used in Land combat (bombardment, etc...). Anti-armor is typically 50% of Penetration.

I would seem to be irrelevant in the game. Japanese "tin-foil tanks" seem to do just fine against T-34/85s and/or any other Allied tank.
el cid again
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RE: Naval Guns: Penetration vs Anti-Armor

Post by el cid again »

This is not my experience. But I have diligently implemented the actual armor of
vehicles. Many vehicles were grossly over-rated in terms of armor. Those with values
like 3 mm and 5 mm fare terribly. One reason is that I permit .30 caliber weapons to
penetrate 9mm, and .50 cals 12 or 13 mm. Even 6.5 mm rifles penetrate 8mm. That means
a host of weapons are deadly to a vehicle with 3 to 8 mm of armor.

Note that one does not need to "penetrate armor" to destroy a tank. The game well handles
the abstraction that infantry are dangerous to tanks in other ways. A Japanese unit with a
handful of tanks of marginal firepower and armor does not do well against a large Allied force
with some heavy weapons. As it should be. Neither do large Japanese armor formations against
large Allied formations (there was one such battle in the Philippines in actual history). As
well - I think there is a national penalty against Japanese ground units in general and/or against
Japanese armor. But if there is, I think it is reasonable simulation. Yamashita wrote the first
serious armor proposal in late 1941. Japanese soldiers did not know how to drive, never mind fix
a tank engine. They were not as capable of mechanized warfare.
el cid again
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RE: Naval Guns: Penetration vs Anti-Armor

Post by el cid again »


This is because the game code likely assumes a side hit as the general case. This is somewhat
compensated for by other features. It is possible to blow up a battleship with a single shell hit -
like HMS Hood. Such a rare event is rationalized to mean you hit something not well protected -
something that was probably explosive and caused the ship's magazines to go up in sympathetic detonation.

Ideally the routine would look at range and specify deck armor at long range. But I am not sure that a 15 inch
gun should be regarded as doing that at 15 000 yards? At 25 000, surely. I need to look at the trajectory. But so
far as I am aware, we cannot look at the algorithm and, in any case, it is not defined in documentation by the original
programmer which is more or less necessary to understand design intent. I think a long and complex program MUST
be documented to be considered good professional practice, but in the US, this is rarely done. [In the West, Germans
are perhaps the most extreme at this. At Mt St Helens the monitoring station program will have many pages of documentation followed by
a few lines of code right inside the program. In Russia, it is - or at least was - SOP to document every program. In
the US, documentation takes time - and market pressures do not allow it. Also, there is a sense of "we don't want
anyone else to be able to work on it" = job security.

ORIGINAL: Dili

"penetration at range % " is not what i am seeing in DaBigBabes, for example 15in/42 BL Mk I have 740mm, that kind of values are not possible at 14-15kyd.
US87891
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RE: Naval Guns: Penetration vs Anti-Armor

Post by US87891 »

Hello Spence. Not sure exactly how John set it up. Do know he set Pen depending on caliber of the gun. Pretty sure the 5” class was calculated at 1000m and think BB guns were calculated at 5000m. Doesn’t really matter so long as things are consistent within caliber classes. Our programs use dynamic calculations so we do not tend to think in those terms anymore. Given a Pen number and the gun/shell ID, It should be fairly easy to back out the range value with Facehard. Once you have the range for one gun in a caliber class, all the rest of the class will be evaluated at the same range.
Alfred
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RE: Naval Guns: Penetration vs Anti-Armor

Post by Alfred »

ORIGINAL: US87891

Hello Spence. Not sure exactly how John set it up. Do know he set Pen depending on caliber of the gun. Pretty sure the 5” class was calculated at 1000m and think BB guns were calculated at 5000m. Doesn’t really matter so long as things are consistent within caliber classes. Our programs use dynamic calculations so we do not tend to think in those terms anymore. Given a Pen number and the gun/shell ID, It should be fairly easy to back out the range value with Facehard. Once you have the range for one gun in a caliber class, all the rest of the class will be evaluated at the same range.

Relevant threads where JWE explained his methodology (without disclosing the game's algorithms) are:

tm.asp?m=2905617&mpage=1&key=penetration&#2908051

tm.asp?m=2905617&mpage=1&key=penetration&#2908051

tm.asp?m=2887820

JWE's above comments are essentially a conversation with JuanG and Nikademus so their comments also have to be taken into account. I won't bother summarising the threads as nowadays too many people completely misrepresent what I say just so that they can claim I am wrong and their quite erroneous conclusions are justified. Means that those seeking "enlightenment" will have to wade through the dense info provided in the above threads by themselves.

Alfred
el cid again
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RE: Naval Guns: Penetration vs Anti-Armor

Post by el cid again »

ORIGINAL: US87891

Hello Spence. Not sure exactly how John set it up. Do know he set Pen depending on caliber of the gun. Pretty sure the 5” class was calculated at 1000m and think BB guns were calculated at 5000m. Doesn’t really matter so long as things are consistent within caliber classes. Our programs use dynamic calculations so we do not tend to think in those terms anymore. Given a Pen number and the gun/shell ID, It should be fairly easy to back out the range value with Facehard. Once you have the range for one gun in a caliber class, all the rest of the class will be evaluated at the same range.

This confuses me. What happens when a heavy gun engages at medium or short range? Using armor penetration values for a
different range seems inconsistent. Is it not better to rate all guns for short range penetration values?
US87891
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RE: Naval Guns: Penetration vs Anti-Armor

Post by US87891 »

No it is not. It is better to understand the mathematical calculations that the algorithm is performing and use variables with appropriate starting points and appropriate numerical ranges for the program's boundary conditions.
el cid again
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RE: Naval Guns: Penetration vs Anti-Armor

Post by el cid again »

My question is about how the code SHOULD operate, not a dispute over how it
DOES operate. I once worked on professional simulations for USAF, NASA, etc
at Boeing (at, not for - I was a "resident computer engineer" from a different
defense contractor with my desk at the Boeing Spaceflight Center). I am
confident the description is sincere and correct within your understanding.

[I have correspondence with a chief AE programmer saying that he is never sure
of anything. "After two years working with LCU, I thought I had a firm grasp of
how code works. Today, after finding a branch, I am sure of NOTHING." Emphasis
in the original.]

My point is that this is NOT the best way to model this problem.

That said, AE is almost elegant in the simplicity of its code concepts. And some of
them work astonishingly well. IF one feeds in good aircraft data (which I admit
is hard to do) air combat works better than almost any other model - even those
dedicated to it and far more elaborate). It is impressive. The trick is to figure
out how to define maneuverability and durability in a way that is objectively "fair"
- which is a whole lot easier to say than to do. I am not trying to be overly harsh
about the code. Just saying - a correct approach must define penetration on a
standard basis for ALL weapons. Remember, a heavy gun usually has more range, so it
can shoot at all ranges, while a light gun cannot. As well, the chance of a hit at
long range is very low - it won't happen much. It is much more important to get
penetration right at SHORT range - where it applies to ALL guns - than it is at long
range - where in the nature of things, only long range guns can reach anyway. If one
wanted to be extremely simple, one might define ALL long range hits as "deck armor"
hits - and short and medium range hits as "side armor" hits. But penetration needs to
reflect what happens at short range - where most guns will score most hits. Unless one
writes very sophisticated code - which AE does not go for. Instead, the philosophy was
to use random numbers to reflect other possibilities. Which is NOT a bad philosophy
and certainly is simple. The original programmer loved "die rolls" - and it is often
a very fine mechanism.
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