Horizontal armor penetration improves with greater distance.

[arkhangelsk]

At least according to the armor calculator (the penetration has been decreasing as I close the battleship, but I forgot to take pictures then).

And man did the shots bounce a lot, even considering the ricocheting - I am worried that's not just an armor calculator glitch, but what the computer "really" thinks and is making my shells bounce off on that basis.

[Ink]

Greetings,

it is as intended, the farther away is the target, less sloped is the target's top, less effective armor is.

Ricochet info is basic, it only shows side ricochet crude estimation.

[Durin]

also known as "Plunging Fire"

Edited February 14, 2020 by Durin

[arkhangelsk]

What I'm thinking of is my penetration against the side armor, not the top deck armor. Isn't the number on the right supposed to estimate the side armor penetration?

BTW, while these are not the best shots, what really rang my alarm bells was how my estimated overall penetration chance actually dropped as I closed. But they are not in these pictures. Oh well, I'll pay more attention next time I have to close a battleship to stab it to death and send some screenshots if I spot it again.

[Nick Thomadis]

The penetration info updates also according to the angle of the target ship, so this can be a reason of a low pen chance.

[arkhangelsk]

The angle of the ship was approximately 90 the whole time I closed. It is one of those situations much complained about - you close and close at a ship already on Retreat mode and it keeps pointing its stern at you. (BTW, the reason why the distance was opening in the above shots is that I have, like many people, expended my entire ammo stock of 17" shells and am forced to retreat).

[Steeltrap]

On 2/15/2020 at 11:09 AM, arkhangelsk said:

What I'm thinking of is my penetration against the side armor, not the top deck armor. Isn't the number on the right supposed to estimate the side armor penetration?

BTW, while these are not the best shots, what really rang my alarm bells was how my estimated overall penetration chance actually dropped as I closed. But they are not in these pictures. Oh well, I'll pay more attention next time I have to close a battleship to stab it to death and send some screenshots if I spot it again.

"pen v/h" is "Penetration Value of Vertical/Horizontal Armour", where vertical/horizontal means how the armour is placed relative to the surface of the ocean. 

Thus v/h = "Side/Top" or, in ship's armour layout terms, "belt/deck".

In fact the calculator sort of tells you that a bit lower when it says "side/deck: 82% (6 degrees)", which is saying a shell has an 82% chance of striking the side (presumably at a 6 degree from horizontal angle of impact).

As an aside, 12" of horizontal pen at that range on 6 degrees impact from 10.5km seems much too high (Yamato's 18.1" would strike at an angle of 7.2 @ 10km, and penetrate perhaps 6.6" of horizontal armour falling at an angle of 16.5 degrees @ 20km, so 12" horizontal pen at 10.5km for a 17" seems odd to say the least, but that's hardly relevant). It might be entirely reasonable within the context of how the system works, but we've never had any of the armour and penetration mechanics explained so we sort of expect it to match real world available data.

As to penetration chance it depends on a bunch of things. Yes, range will change v/h armour pen values. Closer you get the higher the vertical and lower the horizontal, and the reverse of course as you get further away. You then have ricochet chances that are altered based on relative facing.

What could well have been happening as you got closer was your chance of hitting the deck was going down (as it should) yet the vertical penetration had not increased sufficiently to overcome the belt armour. In that case you'd see the "pen chance" getting LOWER as it alters to reflect the chance of hitting the belt or deck, the pen values for them, the base thickness of them and then the 'effective' thickness of them.

[arkhangelsk]

21 hours ago, Steeltrap said:

As an aside, 12" of horizontal pen at that range on 6 degrees impact from 10.5km seems much too high (Yamato's 18.1" would strike at an angle of 7.2 @ 10km, and penetrate perhaps 6.6" of horizontal armour falling at an angle of 16.5 degrees @ 20km, so 12" horizontal pen at 10.5km for a 17" seems odd to say the least, but that's hardly relevant). It might be entirely reasonable within the context of how the system works, but we've never had any of the armour and penetration mechanics explained so we sort of expect it to match real world available data.

Oh, I think I know what happened now, thanks - I confused the V-pen and the H-pen because at the ranges I was in the Side penetration should be larger, but it isn't because of the extreme angle.

As for this, it is roughly as per the table - unmodified (using Black Powder), the 17" Mk 5 has a deck penetration of 14.7 inches of iron at 10000m. Every penetration value in this game is of iron.

[Steeltrap]

20 hours ago, arkhangelsk said:

As for this, it is roughly as per the table - unmodified (using Black Powder), the 17" Mk 5 has a deck penetration of 14.7 inches of iron at 10000m. Every penetration value in this game is of iron.

That may be true, but Krupp Cemented works out at roughly double iron according to NavWeaps.

It's also true that the interaction between large projectiles and armour is notoriously complex, and all nations altered their armour in terms of level of face hardening and other aspects in response. They also, of course, altered their shells, too, in response.

Regardless, that level of penetration v basic iron, given the angle of impact at such a short range (angle of fall will depend on the angle of elevation of the gun to reach that range, so a very long ranged gun will use low elevation and thus a flat trajectory) seems excessive. As I pointed out, the guns of the Yamato would have struck at about 7.2 degrees at that range. Given the penetration of 6.6" armour at 20km, and that it would DECREASE with range until almost certain to be deflected/shattered due to the striking angle, let's imagine 4.5" at 10km (probably too high). That's still roughly 9" of iron.

In short, I still think 14.7" of iron at only 10km is excessive.

Interestingly, there's a person associated with NavWeaps who has done a LOT of work on studying this stuff and has written programmes that are freely available for download.

I wonder if our devs have used or at least investigated them? Call me crazy, but I certainly would be looking very closely at it given it has all sorts of things (including metallurgy and shell construction, the works).

Cheers