Rig for depth charge!

[Sniper297]

Been playing with some numbers in DepthCharges.zon and NSS_Sargo.zon to see if I can make the game a bit more analog. Biggest trouble with stock is it's digital, either on or off - no hits no damage or one hit so much damage so rapidly there's no point in even having a damage control crew.

One necessary clarification, English translation failure - "CRASH" depth in the CFG file means the depth at which a "crash dive" will level off. In the .zon file they actually meant CRUSH depth, the depth at which the pressure hull starts taking damage. That's a percentage variable too, if your "crash" depth is 150 you'll start losing hit points at 160 when you're fresh out of overhaul. If your hull damage shows 50% then your new crash depth is 75, since that's 50% of the original 150.

Stock numbers (SARGO);

ArmorLevel=25
Hit_Points=320
CrashDepth (CRUSH depth)=152
CrashSpeed=2.0
Rebound=0.45

What that means is below 152 meters (501 feet) you start losing 2 hit points per second, but since the damage is cumulative it takes a lot less than 160 seconds (2 minutes 40 seconds) before total collapse - as the hull damage increases the crash depth decreases so by staying at the same depth you get further below crush depth since that is moving up. In other words at 550 feet you're 50 below crush depth, taking 2 HP per second. Stay there for 1 minute 20 seconds and your hull is 50% damaged, the new crush depth is now 250 feet, so now you're 300 feet below crush depth without having moved. This is the cause of the "instant death" syndrome, the combination of decreasing crush depth while increasing actual depth from flooding which causes the damage to happen faster and faster.

Numbers I'm playing with;


ArmorLevel=25
Hit_Points=1920
CrashDepth (CRUSH depth)=120
CrashSpeed=0.1
Rebound=0.45

120 meters is 396 feet, 500 feet seemed a little excessive for a Sargo class to me. The 0.1 CrashSpeed however means ONE point of damage every 10 seconds, and with 1900 hit points you'd have to stay below crush depth for 15 minutes to do serious damage, and once you came back up you'd still have enough hit points for the damage control team to have some actual hope.

The other banging around from depth charges;

MinEF=170
MaxEF=230
AP=0.0
MinRadius=4.5
MaxRadius=40

So the max damage of 230 hit points is done if the charge explodes within 15 feet of the hull - with a max of 320 HP for the whole sub that don't leave much. 170 hit points at 132 feet distance seems a little excessive, and zero damage outside that radius seems kinda weird too. So I hacked that;


MinEF=70
MaxEF=200
AP=0.0
MinRadius=2.0
MaxRadius=90

That feels more reasonable, a charge going off within 300 feet does a little damage, one within 6 feet does a lot, and when you're hit you're usually hit with multiple charges at one time so the 6X increase in hit points is necessary for survival.

Only oddball I've found from this is the idiots in the destroyers - in real life they had enough sense to speed up before rolling ash cans off the stern racks, in game they sometimes drop shallow charges while moseying along, blowing themselves up. My thinking is it would be better to figure out a way to make them smarter instead of reducing the blast radius of the depth charges, unfortunately there's no way to do that. One possibility is reducing the damage at max radius to 50, see if fewer of them blow off their fantails.

[TorpX]

So the max damage of 230 hit points is done if the charge explodes within 15 feet of the hull - with a max of 320 HP for the whole sub that don't leave much. 170 hit points at 132 feet distance seems a little excessive, and zero damage outside that radius seems kinda weird too.

I'm not sure, but I don't believe this is how it works. I think the game 'rolls dice' and generates a random number between 320 and 170 and applies that at a diminishing level to zones between 4.5 and 40 m. That is what I've been lead to believe.

Can anyone confirm this?

[Sniper297]

Can't confirm it but it wouldn't surprise me - that's exactly how the dud torpedoes work, and I strongly suspect the dice are loaded.
Latest numbers seem to be working okay, instead of half a dozen escorts blowing their own fantails off in a single battle I had only one during an entire patrol pull the Barney Fife - creeping along at 3 knots and rolling a shallow charge off the side rack was a bad idea in real life too. They don't have to be cranking along at full tilt boogie to escape the blast effects either, any reasonable speed will keep them clear. And my sub don't get away scot free 50 yards outside the pattern, there's some minor damage, and it's cumulative too - dozens of near misses do the same damage over time as a hit. Not very scientific, but it just FEELS more realistic to me.

[TorpX]

Yeah, the escorts blowing themselves up is very unfortunate. I don't know why Ubi couldn't just make the DD's and their DC's historically accurate. Too much in a hurry, I guess.

[HertogJan]

Originally Posted by TorpX

Yeah, the escorts blowing themselves up is very unfortunate. I don't know why Ubi couldn't just make the DD's and their DC's historically accurate. Too much in a hurry, I guess.

That and soooooooooooooow much els

[TorpX]

Originally Posted by HertogJan

That and soooooooooooooow much els

Ha, ha, ........................ yeah.

[james_nix]

Boy, I tried these changes last nigh on my Sclass and it was so cool!

As I slowly crept past max depth, there wasn't the usual instant death.

One foot under I heard broken glass. A foot or so more broken glass, pops, the lights flicker. No damage yet, but boy, you could tell it was coming! It was like the whole boat was saying that going that deep was a bad idea!

I can image how cool this would be when you have destroyer over you so you try to risk a couple of feet below max depth, having to decide which is worse. Damage from depth or damage from a depth charge!

[Sniper297]

Resurrection of an old post, but might be worth the exhumation. One correction to the original post - engineers design safety factors of at least 150% into most things, so if they certify a fighter plane to a limit of 6 Gs, they actually designed it to take 9 or more before something breaks.

Fleet boats, like any other military machine, are designed according to government specifications, and have to meet or exceed those specs before being accepted by the military. So the test depth for a sub is the depth the boat builder will guarantee, and the civilian workers take it out for the first test dive, dive to the test depth and no deeper, at which point the Navy accepts delivery. The actual design depth is at least 200% of the test depth, so for a 250 foot test depth you can be sure it's actually safe down to 500 feet or more. 300 feet test depth is really 600 feet, 400 feet means you would expect implosion (or other catastrophic failure) somewhere below 800 feet.

Assuming a brand new sub with no damage, that is, got one that's been through several deep dives below test depth and several depth charge attacks there will be more metal fatigue and cracked welds in the ribs, etc. Which is part of the reason the engineers include the "fudge factor" to begin with, design it to withstand more stress than actually required and you can be sure it will withstand at least the original requirements after several years of use and abuse.

S class is a different animal - the PORPOISE was the first with an all welded hull, the S class used rivets like all previous subs, and after 20 years of operation/stored in mothballs/recommission and more operation/back into mothballs/recommission and overhaul etc. they had some serious problems and probably quite a few loose rivets. Test depth of 200 feet, actual critical depth around 250 - not because of hull failure, but because below 250 feet there were so many leaks that the pumps couldn't keep up with the water coming in. Any fleet boat would know it was in trouble before the actual implosion due to leaks around the periscope shaft seals, propeller shaft seals, exhaust valves, and assorted other through-hull mechanisms, but the S boat was actually more likely to flood completely instead of imploding.

For PORPOISE and later you can pretty much double the "max depth" (test depth) and be close to accurate.

[james_nix]

I actually had and idea for a mod, that every time you played, you would run a little randomiser program that would load up a different depth for a particular boat.

Every boat would have different depth it could go past test depth, I remember reading that when O'Kane first got the Tang, he took it down until things started to break to see what the actual depth was, since every sub was unique on how far it could go past test depth.

It would add some uncertainty when the destroyers are going at you if you didn't do a thorough test dive earlier.

I was using Websters S-Class mod, so 200 feet was test depth.