damagelethality of depth charges

[spence]

I think the ASW routines are pretty good now.

Taken in isolation Cid's comments re ASW give the impression that ASW in WW2 was pretty ineffective. Close to 1000 dead axis subs from that conflict belie that contention. Yes, airplanes, mines, bombs, acoustic torpedos and accidents all killed some, perhaps the majority, but plain old depth charges killed a very statistically significant number. The same is very large, larger than any other class except merchies.

[DuckofTindalos]

As usual, he's talking out the back of his head; of course depth charges were effective. That dozens might be expended to get a kill is irrelevant, they were effective all the same. Next he'll be lecturing us in his usual condescending tone that flak was ineffective as well...

[Ron Saueracker]

but odds are long they OVERSTATE the value of DCs - not understate them.

ElCid

I have to agree here. Even with the new routines the chance of a severe DC hit is fairly high. And this without the escorts dropping multiple DCs from the stern racks...in WITP each rail only drops one DC per attack when IRL the standard was approx 3-4 per rack per pass. I've been thinking about trippling the number of racks per "turret" to simulate this series of DC drops, especially after so many folks complained that subs are too hard to hit now!![;)] I think I'm going to leave the ASW as it is because for one thing it would be a massive effort changing the data regarding every escort class based on how the editor works now, each member of the class would need to be redone. Thousands of data revisions would be necessary.[X(] For another, play has revealed that DCs are in fact possibly too effective still and coupled with the overkill air search phase where subs are always being attacked on the surface, the current ASW might "end up" about right. Correcting the surface ASW might frig the overall results currently achieved by the current weak surface ASW and way too common air vs sub attacks/kills.

[Speedysteve]

Personally i'm happy with the current ASW model and the results it produces

[DuckofTindalos]

Concur. Now where's my TOAW turn, slowpoke?[:'(]

[Speedysteve]

I'm at work butthead. You'll have to wait until i've received and analysed all the reports from the frontlines about your mass breakthrough. Turn will be with you in approx 4-6 hours

[DuckofTindalos]

I'll allow you an extra 45 minutes to collapse into a blubbering ball in the corner once you see how badly I've clobbered you...[:'(]

(okay, now I even disgusted myself)

[Speedysteve]

All due respect. If you HADN'T clobbered the Italians as they were - ill trained/ill equipped/shocked/dispersed - then you have serious computer operation problems[;)]

[DuckofTindalos]

Bah... Excuses, nothing but excuses... I'm not beating on them, either...

[Speedysteve]

The best opponent is always gracious in defeat and accepts the true situation when they are winning[;)]

[DuckofTindalos]

Nah... I prefer slinging ****... you should know that by now...

[Speedysteve]

I know. I'm trying to improve your standing[;)]

[Kereguelen]

ORIGINAL: pauk

I as Japan player didn't sink a single one sub after the last patch (to be honest, there wasn't many sub actions, but ....)

on the other hand, Allies can sink japs subs but they need more attacks then before. I guess that die roll is important - one of my sub was hit with 6 DC i think (all of them were "fire" hits shown on CR) but flooding stopped at 67 and my sub survived....)

Hi,

can't be patch related. Depends (as most things in the game) on players' actions.

In my game vs. Mogami (game is currently in August 1943), my esteemed opponent just managed to severely damage two of my (US) subs in one turn: One was hit by depth charges in open waters near Palembang (probably by a dedicated IJN destroyer hunter-killer group, maybe just escorts for a bigger ship, don't know for sure because the destroyers spotted my sub first). The other was hit by a plane (if I remember correctly by a Sally, probably on ASW mission) somewhere near Tarakan (in a deep water hex, I was just too lazy to move this one around).

And, as I wrote before, I managed to sink two Japanese subs in one turn near Cairns sometime in July (in the hex just east of Cairns, the gap in the reef). Third one was sunk by my ASW forces near Port Moresby at about the same time.

K

[herwin]

ORIGINAL: herwin

ORIGINAL: spence

I think a single hedgehog projectile was 24 lbs of explosive...a hit by one of those was very often lethal. I think the 300 lb depth charge the Allies started the war with had about the same lethality as a hedgehog if it exploded within 10 feet of the hull of a sub.

(Source: Morse and Kimball) A bomb hit on a sub was rarely lethal as most of the blast was vented to the atmosphere. Depth charges were fused to explode at a specific depth, so they had higher lethality and could kill the sub at a distance, but their lethality wasn't that high. During 1944, the ASW escorts used about 700 ahead-thrown charges and 614 depth charges to kill 1.25 subs a month in the Atlantic. The hedgehogs were contact-fused, which meant that they wouldn't explode during the attack unless they contacted something. Since depth charges were guaranteed to explode and disturb the track on the sub, battle damage assessment was very hard to do.

Basically, the value of ASW weapons was in keeping the subs occupied, not in killing them except by rare accident.

By the way, that was 1314 DCs/HHs *per month* to kill 1.25 subs/month that way. The Germans kept about 30 at sea, so that was 44/sub-month!

[spence]

I think you'll find that it took about 10000 heavy AA rounds to knock down a heavy bomber over Germany.  I think the statistics thing can only prove lots and lots of ammunition was used to achieve the "kill" of whatever they were aimed at. 

Surely you are not proposing that Allied ASW was ineffective because of that.  There's not many left but the surviving U-boat men would likely contest that...to say nothing of the fact that the US shipped and supplied lavishly some 60 of its own divisions on the other side of the "pond" along with all that lend-lease stuff to the rest of the Allies.

By 1944, something like 9 of every 10 U-boats that sailed did not return to port.  The U-boat fleet had begun to decline by due to losses but I'm pretty sure it was capable of putting considerably more than 30 boats at sea...I am almost certain that in March 43 the U-boat Command marked the milestone of keeping 100 boats on patrol at one time...just as things finally turned irrevocably against them in the North Atlantic. 

(BTW I know the RN did the lion's share of dirty work (convoys))  

  

[Charles2222]

Nope, slightly wrong there, as a couple of documentaries that I recall have put the Uboat loss numbers at 80%. It's a very common figure that I've seen brought up lots of times in various places.

[madflava13]

In real life, the Halibut (I believe) was hit by a depth charge in 1944 that actually landed on the sub. The charge went off on top of the deck gun, causing massive damage. But despite that, she still made it from the Formosa Straights back to Guam.

[herwin]

ORIGINAL: Terminus

ORIGINAL: ChezDaJez

Actually El Cid isn't far wrong this time. The outer hull was whatever shape the designers decided on but the pressure hull (inner hull) of most WWII submarines was round or oval shaped. Basically all the ballast piping and fuel cells were located between the hulls. Most designers did create somewhat oval outer hulls for improved seakeeping abilities when on the surface.
Chez

My problem is the "a submarine can withstand a nuclear pressure wave" claim...

The water pressure at maximum diving depths is rather impressive. If the sub is at half its maximum depth, it has a lot of spare capacity. To overwhelm the pressure hull of a sub, a small nuclear burst has to be almost in contact. Most of the damage would be due to shock, not static overpressure.

[rtrapasso]

ORIGINAL: herwin

ORIGINAL: Terminus

ORIGINAL: ChezDaJez

Actually El Cid isn't far wrong this time. The outer hull was whatever shape the designers decided on but the pressure hull (inner hull) of most WWII submarines was round or oval shaped. Basically all the ballast piping and fuel cells were located between the hulls. Most designers did create somewhat oval outer hulls for improved seakeeping abilities when on the surface.
Chez

My problem is the "a submarine can withstand a nuclear pressure wave" claim...

The water pressure at maximum diving depths is rather impressive. If the sub is at half its maximum depth, it has a lot of spare capacity. To overwhelm the pressure hull of a sub, a small nuclear burst has to be almost in contact. Most of the damage would be due to shock, not static overpressure.

Well, that's kinda the point. Yes, a sub hull is going to have a lot of "reserve strength" at 1/2 depth. However, the sub hull is designed to be compressed equally and relatively gradually from all sides at once. Having a large pressure wave hit one side of the hull before the other is going to cause a world of hurt.

Look at it this way: we've all seen the pictures of the test houses being destroyed in Nevada. The houses were destroyed when a 5 psi (pounds per square inch) blast wave hit one side of the house before the other. If the atmospheric pressure around the house was raised relatively gradually, there would not have been a problem - it was the asymmetric application of force to one side of the house that destroyed it. Not a perfect analogy since houses are not pressure vessels, but you get the idea...

Similarly, a sub is going to take a shock wave on one side of its hull before the other.

i don't know how the physics would work out - the only "test subjects" i've seen were the ones at Bikini, and they were destroyed in less than the blink of an eye (less than 1 frame on a high speed camera). If anyone has other actual test data i would like to know...

[herwin]

You're asking for classified information.

Yes, shock is the issue. It was also the immediate problem after torpedo hits on gunships. If the gunship survived that, the next issue was loss of structural integrity/flooding. For CVs, fire being the biggest risk, shock aggravated the damage control problem by breaking fuel and water lines,.