Power of guns and submarines armor

[kapura]

Hey, i've started to play SH IV month ago. Yesterday i've started a new campaign (1941 asiatic fleet, s-18). This time i was close to borneo, so i started to patrol north of its shores. Then i've performed my first ever surface attack on a convoy of 9 big merchants accompanied by 4 low end destroyers.

Usually i was avoiding escort, but this time i've received order to sink destroyers. I've managed to sink 2 escort ships (1 never engaged me, second one was heavily damaged and escaped with rest of the ships) and 4 merchants. I'm surprised how easy it was - enemy's accuracy was really low, i've knocked out their guns anyway, but i've also received 3 direct hits. 2 from merchant and i'm not sure about the last one. And nothing really happened. Guys in torpedo room lost ~5% of health and damage to hull integrity was 7%. Something got knocked out, but they repaired it anyway. I play on 100% realism.

I wonder if it's just modeled wrong in the game (i play vanilla with u-boat missions) or ww2 submarines were just quite thick. I suspect it's hull must be hard to withstand the pressure but i didn't expect any sort of protection against cannon shells, even from the waekst units :D Depth charges are so deadly even if they explode far from the ship

[Texas Red]

With FoTRSU, I was engaging a convoy and my periscope was spotted by some eagled-eyed lookouts on a DD, they fired a shell at me and it nearly destroyed my aft torpedo room. I dove down to 250 feet, only for my sub to start going deeper and deeper, I ordered "Blow Ballast!" and I stopped my sub at periscope depth and fought off the attacking DD's to the point they just ran away.

I *think* that there might be an issue with how the vanilla game deals with damage. You might want to send a PM to propbeanie who is an expert with SH4 about your question. He might find this forum and deal with the problem here.


Anyways, welcome to Susbim, Kapura!

[Raider M]

Welcome Captain Kapura!

[KaleunMarco]

Hey, i've started to play SH IV month ago. Yesterday i've started a new campaign (1941 asiatic fleet, s-18). This time i was close to borneo, so i started to patrol north of its shores. Then i've performed my first ever surface attack on a convoy of 9 big merchants accompanied by 4 low end destroyers.

Usually i was avoiding escort, but this time i've received order to sink destroyers. I've managed to sink 2 escort ships (1 never engaged me, second one was heavily damaged and escaped with rest of the ships) and 4 merchants. I'm surprised how easy it was - enemy's accuracy was really low, i've knocked out their guns anyway, but i've also received 3 direct hits. 2 from merchant and i'm not sure about the last one. And nothing really happened. Guys in torpedo room lost ~5% of health and damage to hull integrity was 7%. Something got knocked out, but they repaired it anyway. I play on 100% realism.

I wonder if it's just modeled wrong in the game (i play vanilla with u-boat missions) or ww2 submarines were just quite thick. I suspect it's hull must be hard to withstand the pressure but i didn't expect any sort of protection against cannon shells, even from the waekst units :D Depth charges are so deadly even if they explode far from the ship
first off, welcome to subsim.:subsim:

secondly consider yourself extremely lucky.
in many instances, one direct hit is enough to hole your boat and send her to the bottom...even in Stock.
my comment would be: Well Done, Kaleun. Don't ever frickin' do that again.:D

when you get a secondary order to sink escorts, use your torpedos. make the DD/DE your first target.
or
prior to clicking on the Ship icon for further instructions, save your game, then click on the ship icon. if you get a stupid order to sink escorts, load the just-saved game and do what you wish.
Good Luck!:Kaleun_Salute:

[Aktungbby]

kapura!:Kaleun_Salute:

[Mios 4Me]

Battling it out on the surface with DDs is a very bad idea in almost all circumstances in stock. My only exceptions are at ranges just outside that of the DDs* but still as close to it as possible for accuracy's sake and against heavily damaged DDs in bad weather/dark night when you can see them burning but they can't see you in time.

* Obviously this only works if you have equivalent size guns, usually 5".

[kapura]

Well i think i now understand more or less how it works. I had another encounter with 2 fubuki and one small gunship - i've got hit twice and i sunk after i went periscope depth. I think damaged ship is more or less safe from sinking as long as it's above the water, which could explain why most ships need so much shells to sink, but still i land most of shots below waterline so im not 100% sure about it. Certainly things go bad pretty fast after submerging.

I'm not sure where exactly i was hit during first encounter i've described ( i played with ext camera disabled), but I think pressure hull wasn't breached - there was no leak and my crew men received minor damage. Also I never submerged after getting hit. I decided to fight on surface mainly to check how it's gonna turn out, i didn't expect to be successfull :D However I had very good position, because escort ships were far from each other and i was shielded from their fire by merchants.

Thanks for every reply!

[jimmbbo]

kapura :salute:

Hmm... intentionally engaging in surface combat against DDs - :hmmm:
It's a good thing SH4 doesn't have the "crew mutiny" module installed....

Welcome!
:Kaleun_Cheers:

[Sniper297]

You say "direct hits", but it doesn't take a direct hit to cause damage.
This;

https://www.subsim.com/radioroom/downloads.php?do=file&id=4489

Is the editor you can use to poke through files or mod them.

\Data\Library\shells.dat, .sim, and .zon control all the gunnery. The shells.zon file controls the explosive power, blast radius, and armor piercing level, but unfortunately the only way to find out what shell is for what is to check the parent ID number.

Example, 40mm AP shell in the shells.dat file is 0x13277047c98196cc. Slogging through the shells.zon file I find that number as a parent ID for number 22, click the + to get to 23, and find;

AmmoDamageInfo
MinEF = 6
MaxEF = 10
AP = 20
MinRadius = 0.1
MaxRadius = 0.5

What all that means is it takes away 6 hit points from anything within 0.5 meters, 10 hit points within 0.1 meters. So if it just misses the hull and explodes about .25 meters from the hull, it still takes away about 8 hit points.

Going down to \Data\Submarine\NSS_s18\NSS_S18.zon is easier, since the info is self contained in the file without having to hunt for them unholy 0x13277047c98196cc numbers to find out what's what. Down at the bottom;

ColisionableObject
ArmorLevel = 25
Hit_Points = 500

Been playing with that on a SARGO off and on, the number of hit points is obvious, the armor level looks like it might be a variable - if the overall armor level of the "collisionable object" is twice the armor piercing level of the shell, it does no damage at all wherever it hits. I think. :doh: A shell with an AP around 75% of the armor level will usually do some damage, but not as much as if it's more than the armor level.

Again, it seems to be random because of that min and max radius - a direct hit will do max damage up to the min radius number, and less damage out to the max radius number, and no damage outside that radius.

From SKWAS notes;

MinRadius
The minimum radius of splash damage. The ammunition takes all its hitpoints until this distance.

MaxRadius
The maximum radius of splash damage. The ammunition takes no hitpoints beyond this distance. If 0, no splash damage!

Guns are different from torpedoes, since a direct hit causes more damage than a near miss, but depending on the max radius numbers a near miss does cause damage. So what seems like minor damage from a "direct hit" might actually have been a near miss.

Torpedoes of course are hit or miss with no in between, most of the extensive testing I've done was for this mod;

https://www.subsim.com/radioroom/downloads.php?do=file&id=4380

Which is an assortment of torpedoes with different amounts of explosive power and different sized blast radius to choose from.