And thak you Mr. Woolley for your interesting disertation on mines…very educational!

1… There are floating, moored mines, those big, horned things one sees on World War Two movies. They contain several hundred pounds of (a rather slow) high explosive, and are detonated by pressure on the horns, which contain an acid that sets off the explosion. They are “impact” mines, and occasionally break free from their anchors and float into seaways. They generally are found in deep water, unlike where Cheosan sank. They have immense value as an anti-submarine barrier.

2… There are bottom mines, shaped often like torpedoes because they are frequently laid by submarines. These are not easily moved by fishing nets, are quite difficult to find even by very short wave sonar (not radar) and can even carry nuclear explosives. They run from 500 to 2000 pounds of HE. They can be triggered by an enormous variety of means — electrically from shore, magnetically, acoustically, by pressure wave from a vessel. They often have combinations,and they often have numerical counters so that the explosion becomes almost random. They are the nightmare for all NATO captains in shallow water. They don’t float, they don’t move, they just lie there, deadly.

3…NATO also has artillery-laid anti-tank mines for use on land — and I have been wondering if the recent artillery splashes in January in this area were delivering a new Nork marine mine by artillery rocket. The general artillery equation for oomph is “half the cube of the diameter in inches equates to the explosive in pounds” So a 125 mm shell is 5 inches and holds about 65 pounds of HE. Not much for a sea mine. But a 240mm or 9.5 inch rocket can lay a single 425 pound mine, and that is enough for a big bang in shallow water. Indeed a rocket may be able to carry more explosive than an artillery shell, so this figure may be conservative. I’ve been thinking about this for some time: I can’t find any report that any NATO force has developed such rocket-laid sea mines, since as a whole, NATO hates sea mines since NATO is a sea-projection force. But there were those very strange artillery duels in January in the West Sea in about this area, and I wonder if the Norks did project such mines.

4…Rocket laid mines would not create a coherent mine field. It is “international law” that a country which lays a minefield must disclose its extent. One can expect the DPRK to ignore this law, but it is a really big deal to do so.

S.K. Navy rules out internal explosion as cause of ship sinking

By Lee Chi-dong SEOUL, March 30 (Yonhap) — South Korea’s Navy has tentatively concluded that the sinking of a warship last week was not due to an internal explosion, according to a top presidential official Tuesday.

In his report to President Lee Myung-bak, Navy chief Kim Sung-chan said it is almost certain that the 1,200-ton vessel Cheonan was torn in two due to “powerful outside pressure or an explosion,” according to Lee Dong-kwan, senior secretary for public affairs at the presidential office.

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Ok, starting to get some official conclusions. No internal explosion most likely means either mine or torpedo . . .

he doesn’t look like a military expert, but he DOES look like dr. tobias funke.

And he’s wearing clothes, so he could be a never-nude.