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vanjast
04-28-09, 04:15 PM
Does anybody have any technical info on the shockwave effects of a Depth Charge exploding at different depths.

My logical thinking (which might be wrong) is that the deeper a DC explodes the more the shockwave is contained by the pressure, therefore it's not that effective.

Going to the extreme, say a DC ended up down the mid-atlantic trench. So much pressure would prevent it from exploding, and more likely implode.

The other side of this is that the subs pressure hull is under more pressure at depth, and requires less shockwave pressure to break it. BUT the DC range would also have to be reduced to be effective.

:D

Armistead
04-28-09, 04:57 PM
I highly doubt the game accounts for real life effects.

I thought the game programmed charges to go poof at 300ft. However, I was at 450ft and just happened to be watching my sub in the cam. I noticed a few getting close which should have warned me, then out of nowhere one bullseye that sunk my sub.

I play TMO1.7 and Ducimas said something about sonar conditions relate to how deep charges go off.

XonE:32
05-01-09, 06:11 PM
Does anybody have any technical info on the shockwave effects of a Depth Charge exploding at different depths.

My logical thinking (which might be wrong) is that the deeper a DC explodes the more the shockwave is contained by the pressure, therefore it's not that effective.

Going to the extreme, say a DC ended up down the mid-atlantic trench. So much pressure would prevent it from exploding, and more likely implode.

The other side of this is that the subs pressure hull is under more pressure at depth, and requires less shockwave pressure to break it. BUT the DC range would also have to be reduced to be effective.

:D

Oh man vanjast. You just took away 2 hours of my life. I won't charge you though 'cause it was an interesting 2hrs.:O:

I found your question and thought experiment interesting so I started searching and checking etc etc. Unfortunately I think Armistead is probably correct with regard to what's actually implemented in the sim, but that's just a guess based on the fact that UBI and other designers tend to leave cool stuff like that out.

With regard to technical/historical info I can only offer limited guidance at this time and it unfortunately doesn't answer the question directly. but see for yourself.

DepthCharge1.jpg below unfortunately refers to tests shortly after WWI, but the results I found interesting. (lower half 2nd column)

http://i5.photobucket.com/albums/y189/xone32/SHIV/DepthCharge1.jpg


DepthCharge2.jpg (2nd Column) below is a bit more relevant as it refers to tests conducted on a Tambor in 1940. The drawback here is the depths involved were not in line with your original question. The results however are still very interesting (I think). In fact I wasn't familiar with this book "U.S. Submarines Through 1945: An Illustrated Design History" by Norman Friedman, but because of your post I'd like to get more familiar with it. I just spent the last two hours reading a chunk of it online... so uhh, THANKS.;)

http://i5.photobucket.com/albums/y189/xone32/SHIV/DepthCharge2.jpg

vanjast
05-02-09, 08:11 AM
Thanks XonE:32... interesting non the less :up:
(http://www.subsim.com/radioroom/member.php?u=212011)

XonE:32
05-02-09, 10:08 AM
Thanks XonE:32... interesting non the less :up:
(http://www.subsim.com/radioroom/member.php?u=212011)

Yeah, very. But now I'm depressed Van.:wah:

Where's LukeFF when ya need him? While reading it I thought ..."this sounds like the type o' book the RFB team had at hand when making their mod, I bet he's got a copy." I was all over the forums yesterday just lookin' at different stuff and I think I even saw him reference it in another post somewhere.

After reading those pages I thought, "I could really get into this." So I looked online... Holy Sh!t, it's hard to find to buy and it's frickin' expensive to boot. For me anyway. And apparently my library blows chunks.


All that aside, you can probably extrapolate from the little that's written there and I'd say your initial assessment is correct regarding the physics of depth and PSI. But I was more surprised at how useless they (DC's) were overall unless they were so close. But at the same time one really well placed shot would ruin your day down below. Whether it was a dramtic hull breach which I get the sense was probably pretty rare, or creating minor damage that would lead to an oil slick which would be just as bad. Nothing like telling your enemy exactly where you are. Add advanced ASW on top o that and you can see how and why the DC's got more dangerous as the war went on.

Damn it , I want that book. So if anyone's interested, I'm now taking donations...

Anyone? Anyone? Helllloooo? :D

vanjast
05-02-09, 03:29 PM
That story by RR on the Tambor surviving many accurate DC's begins to add up after reading your 'extract', and possibly my 'depth analysis', and also the fact that the Tambor was half buried in the mud during this episode.

Great stuff :yeah:

LukeFF
05-03-09, 03:15 AM
Where's LukeFF when ya need him? While reading it I thought ..."this sounds like the type o' book the RFB team had at hand when making their mod, I bet he's got a copy." I was all over the forums yesterday just lookin' at different stuff and I think I even saw him reference it in another post somewhere.

Yep, I have this book and his earlier one on naval radar. Both books are goldmines of information, and I've no doubt his other books are just as well-written.

But I was more surprised at how useless they (DC's) were overall unless they were so close. But at the same time one really well placed shot would ruin your day down below. Whether it was a dramtic hull breach which I get the sense was probably pretty rare, or creating minor damage that would lead to an oil slick which would be just as bad. Nothing like telling your enemy exactly where you are. Add advanced ASW on top o that and you can see how and why the DC's got more dangerous as the war went on.The big idea behind a depth charge isn't so much to blow a hole in the side of the submarine (though the result is no doubt effective) but rather to shake the submarine apart, which in turn springs leaks, causes fires, knocks the crew around, etc. The weapons that really did a lot of damage in-close to submarines were the hedgehogs and, of course, homing torpedoes.

XonE:32
05-03-09, 11:13 PM
Yep, I have this book and his earlier one on naval radar. Both books are goldmines of information, and I've no doubt his other books are just as well-written.

Gimme, Gimme. If I had 60 bucks lyin' around I'd order it as it completely sucked me in the other day. The changing nature, desires, requirements etc.. of the sub development program throughout the 20's and 30's (from the little I read) seemed almost frenetic.

LukeFF
05-04-09, 12:52 AM
Gimme, Gimme. If I had 60 bucks lyin' around I'd order it as it completely sucked me in the other day. The changing nature, desires, requirements etc.. of the sub development program throughout the 20's and 30's (from the little I read) seemed almost frenetic.

http://www.amazon.com/U-S-Submarines-Through-1945-Illustrated/dp/1557502633/ref=sr_1_1?ie=UTF8&s=books&qid=1241416342&sr=8-1

:)

XonE:32
05-04-09, 09:53 AM
Thanks Luke,

That's only 50 in the current Cdn peso. Not bad.

What irks me is I've got 65 in an online account at frickin' Chapters-Indigo, but it's listed as "unavailable". Losers. Living north of the 49th can sometimes blow.

I did find a copy with a "slight smoke smell to the pages:timeout:" somewhere for even less.