And are they any different nowadays?
Basically the ship would tow two buoys behind the ship called paravanes. Attached to the paravanes were steel cables what would sweep just under the surface a few hundred yards to the right and left of the ship, the cables would slice through the mine’s mooring cables and it would float to the surface. Once the mine was floating sharpshooters would fire at it with rifles until it exploded.
Some mines were set off be a magnetic field so many minesweepers had wooden hulls, unfortunately I don’t know much about modern sweepers except the Navy does not have enough of them, during the Gulf war two of our ships were severely damaged by Iraqi mines USS Tripoli and USS Princeton. The Navy also can sweep mines with a helicopter towing a sort of paravane sled through the water.
Oo, oo… raises hand I can tell you how the latest Minesweeper works. If you can find a November 2000 edition of Car and Driver, you can even see [shameless self-promotion] the pictures I took of it in Kosovo [/shameless self-promotion.]
Anyhow, this particular minesweeper is based on the flailing method of mine clearance. Here’s a pic of the Compact 320 Minecat. At the front of the minesweeper you have these two arms sticking out, on which a rotating axle sits. On this axle, you have a bunch of heavy-duty chains with a piece of metal at the end, which helps to dig into the dirt. Once the machine is started up, these chain flails wizz around and dig into the ground, sending up big chunks of dirt, grass and, occassionally mines. Normally the mines do explode, and the Minecat is designed to withstand an anti-tank mine exploding right beneath the operator cabin.
Now, this is only good enough for military clearance. It’s something like 95% effective. For an area to be considered clear for civilians (as in Kosovo) you have to send in manual clearers to finish up the job. The way the Minecat is being used there today is basically to do an initial sweep and to establish where the mine lines are. The Serbs were pretty good at keeping records of what was where and actually laid mines according to the Geneva convention. Oddly enough, though, Kosovars were known to actually STEAL the mines for their own use. At least that’s what the Mine Action Center and UNMIK in Pristina told us.
Um, I think we’ve got some confusion here between land mines and sea mines…
Because of the wooden hulls, minesweeper sailors were envied by sailors on other ships. It’s less noisy than living in a giant metal can, and not as hot in the summer or cold in the winter. “Habitability” is always a big factor to having a happy ship, and sweeper crews, who already have the smallness of their numbers to help morale, enjoy this added advantage. This I know from personal observation. Also, being from Wisconsin, I was proud that minesweeps were built there.
I was told that one of the submarine detectors that I used to calibrate was also used for mine detection.
It used magnetic anomally detection for sub detection. It would have to have been suspended far over the bow of the ship to be helpful with mines and the sweeper would have to be moving very slow.
Modern minsweepers have fibreglass, wooden, or fibreglass-covered wooden hulls. From this site:
FAS on modern minesweepers.
If you want to know more about Naval Minesweeping techinque than you ever thought existed, here’s a fairly complete bibliography.