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2010-05-22 China-Japan-Koreas

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Posted by Steve White 2010-05-22 00:00|| || Front Page|| [3 views ] Top

#1 Someone with better tech knowledge can correct this, but my old Cold War memory says: Close to shore (islands), (relatively) shallow waters, high currents = tough sonar conditions likely, be it in the coastal areas of the Barents sea or the Yellow sea. Good place to hide a sub if you can keep station.

I wonder if its more difficult to detect if the Korean patrol boat were just using passive against an electric boat, no active pinging (And even then I'm not sure that active would gain much in shallows other than a lot of multipath noise).

How bout you bubbleheads chime in?

Posted by OldSpook 2010-05-22 01:04|| 2010-05-22 01:04|| Front Page Top

#2 I understand that there are certain conditions where sonar actually bounces off of layers of water like a mirror. Perhaps this is relevant here, but I doubt it.

Was the torpedo going fast or slow? Was the Cheonan going fast or slow? Was the Cheonan heading straight for the torpedo or at an angle?
Do the Norks make this model of torpedo? Did they get an assist in designing it? What kind of technology does this torpedo have? I understand that the Norks made the sub, but did they develop the tech or did they get an assist, probably from the Chinese again? Iran will have this, no doubt. Also, a couple years back, I remember that Russia helped some drug folks, I think in Columbia, manufacture primitive drug-running subs.

If that sub is 130 tons, I think that means it displaces less than about 120 cubic meters of water, so it's maybe 3x3x12 meters or so? That doesn't sound like much of a home for two or three days. Probably a crew of two or three? Probably has a diesel motor that it used to bug out right away after the Cheonan was hit by the torpedo. I wouldn't think batteries would let it move fast for more than what, three hours or so? (WAG!)

It'd be a shame if one of these were found caught in a net somewhere. I hear that giant squid can be a real problem for them, too. Or maybe one of their propellers could get bent and cavitate a bit or mysteriously fall off in the middle of a mission. How embarrassing.

Posted by gorb 2010-05-22 01:56|| 2010-05-22 01:56|| Front Page Top

#3 How bout you bubbleheads chime in?

They always do. Loudly.

Posted by Shipman 2010-05-22 06:06|| 2010-05-22 06:06|| Front Page Top

#4 If that sub is 130 tons, I think that means it displaces less than about 120 cubic meters of water, so it's maybe 3x3x12 meters or so? That doesn't sound like much of a home for two or three days.

It sounds like the kind of semi-submersible boat the drug runners use in the US that the USN cannot detect without an humint hint. CBGs are at risk to a swarm of such vessels and so not have sufficient escorts to defend against them.

The boat doesn't have to stay on station, it only has to show up when prey is in the neighborhood. Or sortie for a day or two when the weather is nice and maybe get lucky. That's all they have to do, get lucky once.

They aren't conventional warriors. They're terrorists. That's why they so quickly hitch up with drug runners. We're playing a suckers game by sending warriors to fight with them. And we're going to lose economically if it's as long a war as I suspect it will be.

Posted by Nimble Spemble 2010-05-22 06:53|| 2010-05-22 06:53|| Front Page Top

#5 I understand that there are certain conditions where sonar actually bounces off of layers of water like a mirror. Perhaps this is relevant here, but I doubt it.

thermoclines and prolly not relevant at these depths.

/not a bubblehead, but watch a lot of movies and read a lot.... and currently staying at a Holiday Inn. No, really. I am

Posted by Frank G 2010-05-22 09:02|| 2010-05-22 09:02|| Front Page Top

#6 ;-) Frank.

Posted by lotp 2010-05-22 10:21|| 2010-05-22 10:21|| Front Page Top

#7 It sounds like the kind of semi-submersible boat the drug runners use

It's a true mini-sub. Photo.

Posted by ed 2010-05-22 10:54|| 2010-05-22 10:54|| Front Page Top

#8 I think the more important question is why they sank the Cheonan.

Posted by Deacon Blues 2010-05-22 20:47|| 2010-05-22 20:47|| Front Page Top

23:24 Thing From Snowy Mountain
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