Norway anti mine: help wanted

[Bobanderson]

Righto, TDF friends. At the bows of many of the ships here in Norway are raddeldaddles, a form of paravane/antimine defence. If anyone can offer a full explanation as to how they work, we would be very interested to hear you views..


https://scontent-frt3-1.xx.fbcdn.net/v/t1.0-9/q84/s851x315/13263702_10154312576174260_8088267659380839110_n.j pg?oh=2788e12baae1314aeb47c54f6af00b30&oe=57C1E01B

[Paul Evans]

Righto, TDF friends. At the bows of many of the ships here in Norway are raddeldaddles, a form of paravane/antimine defence. If anyone can offer a full explanation as to how they work, we would be very interested to hear you views..


https://scontent-frt3-1.xx.fbcdn.net/v/t1.0-9/q84/s851x315/13263702_10154312576174260_8088267659380839110_n.j pg?oh=2788e12baae1314aeb47c54f6af00b30&oe=57C1E01B

Late version of a Hammer box? probably to small!!

Warpus, Water powered siren?

How big are they?

[Bobanderson]

it is about 2m long...

[Noggin the Nog]

Despite being a dedicated squidgy diver, this has me intrigued. I was surprised at how unhelpful Google was, although I was fascinated by the paravane's other name "Oropesa".
Will be following this with interest.

[braun]

Despite being a dedicated squidgy diver, this has me intrigued.
Will be following this with interest.
Much the same here. And the other thread re a possible newly found wreck.

[ScubaHogg]

Not sure if this is what you want, but…

Operationally, they were streamed from the bow of a ship moving through a minefield area. They normally had wings to prevent them from being pulled back against the deploying ship, and a depth control mechanism to keep it at a certain depth. As it moved through the water, the cable attached to the paravane would encounter the cable securing a mine to the depths. The tension on the line would pull the mine towards the paravane. At this point, either the cable securing the mine would be cut, freeing the mine and allowing it to shot at to detonate it, or I believe that some paravanes had explosive charges and would explode and detonate the mine. The paravanes were effectively consumable items and could be replaced on the end of the cable if lost or damaged by the mine exploding.

[Paul Evans]

Not sure if this is what you want, but…

Operationally, they were streamed from the bow of a ship moving through a minefield area. They normally had wings to prevent them from being pulled back against the deploying ship, and a depth control mechanism to keep it at a certain depth. As it moved through the water, the cable attached to the paravane would encounter the cable securing a mine to the depths. The tension on the line would pull the mine towards the paravane. At this point, either the cable securing the mine would be cut, freeing the mine and allowing it to shot at to detonate it, or I believe that some paravanes had explosive charges and would explode and detonate the mine. The paravanes were effectively consumable items and could be replaced on the end of the cable if lost or damaged by the mine exploding.
The tail looks like no other paravane I have ever seen, looks like the rear end of an aquazep ffs. :-?

Bob, any of the others you have seen have foils?

[Iain Smith]

At the bows of many of the ships here in Norway are raddeldaddles

As "raddeldaddle" appears to be a Googlewhackblatt (https://en.wikipedia.org/wiki/Googlewhack#Variations), in that the only result returned is a link to this thread, is it possible that you have coined a neologism?

Is the picture you have posted typical of the devices you are seeing? There seem to be a lot of fins in the tail for something intended to move through water (but, equally, more than one would expect if this were the tail of something air-dropped).

[Iain Smith]

Is the picture you have posted typical of the devices you are seeing? There seem to be a lot of fins in the tail for something intended to move through water (but, equally, more than one would expect if this were the tail of something air-dropped).

I take that back. I think this is what you are looking at:

http://i.imgur.com/0ELYrTE.jpg

[Kalahari Diver]

I Think the original name for the paravane and cutting cable for minesweeping was the "Oropesa Sweep" named afer HMS Oropesa which was used to develop the technique.

David.

[londonsean69]

Text and images here - http://archives.imeche.org/archive/engines/first-world-war/paravanes

[Iain Smith]

I take that back. I think this is what you are looking at:

http://i.imgur.com/0ELYrTE.jpg

It appears that this was called an "Otter-Gerät" or a "Räumotter". See this Reddit (https://www.reddit.com/r/WarshipPorn/comments/2drkfe/minesweeping_the_hard_way_german_sperrbrecher_of/)

Is it possible that "Raddel-daddle" actually refers to "Dazzle" maritime camouflage (the oblique zebra-stripes intended to confuse the enemy as to the true course on which a ship was sailing), which the Americans referred to as "Razzle-Dazzle"?

[Kalahari Diver]

Otter boards are the vanes used to open a trawl net so similar background.

David.

[matt]

I didn't find anything called raddeldaddle but did find an interesting video from 1918 on paravanes (from the Imperial War Museum):

http://www.iwm.org.uk/collections/item/object/1060023129

And this which I liked:

http://www.mcdoa.org.uk/images/Merchant%20ship%20fitted%20with%20Vickers%20%27M%2 7%20type%20paravane%201920.jpg

WTF is this raddeldaddel...

Matt.

[matt]

It appears that this was called an "Otter-Gerät" or a "Räumotter". See this Reddit (https://www.reddit.com/r/WarshipPorn/comments/2drkfe/minesweeping_the_hard_way_german_sperrbrecher_of/)

Is it possible that "Raddel-daddle" actually refers to "Dazzle" maritime camouflage (the oblique zebra-stripes intended to confuse the enemy as to the true course on which a ship was sailing), which the Americans referred to as "Razzle-Dazzle"?

http://i.imgur.com/nVdsZLp.jpg

[Paul Evans]

Text and images here - http://archives.imeche.org/archive/engines/first-world-war/paravanes

Thats the classic Paravane system and what I expected.


It appears that this was called an "Otter-Gerät" or a "Räumotter". See this Reddit (https://www.reddit.com/r/WarshipPorn/comments/2drkfe/minesweeping_the_hard_way_german_sperrbrecher_of/)

The image is 100% but the drawing is of something different ??

http://i.imgur.com/nVdsZLp.jpg

That is NOT what's in the photo.......

So Back to Bob's question how did this thing work?. The image shows no boards, no cutter, no obvious attachment points for these?
Why would these be added later after installation on the ship? Also Bob photo shows no trace of boards or the braces or the cutter you would expect at the nose?
:nerd:
Without the boards it wont pull a wire out to the side of the ship? its impossible? how does it cut a mine wire if it cant pull a wire out?

Is this a central weighted stabiliser and there would be two paravanes each side? as Sean's classic images? But why go to the trouble of making that complex tail?



Is it possible that "Raddel-daddle" actually refers to "Dazzle" maritime camouflage (the oblique zebra-stripes intended to confuse the enemy as to the true course on which a ship was sailing), which the Americans referred to as "Razzle-Dazzle"?

Thats got to be cock on :)

[MattS]

An image search on "raumaotter"

http://parow-info.de/f/Krake/H-GBT.gif

Source http://parow-info.de/f/fb/Habicht.html

The image is behind a link half way down the page
Klappspiere am Vorsteven für Bugschutz mit Räumotter O.R.G. und / oder mit Geräuschboje-Turbine G.B.T auch

I don't speak German but "Geräusch" appears to translate something like to "noise" and "boje" is "buoy"

So. I guess it's a para-vane with an underwater siren, for targeting acoustic mines.

[Iain Smith]

The image is 100% but the drawing is of something different ??

http://i.imgur.com/nVdsZLp.jpg

That is NOT what's in the photo.......

True...hmm...


So Back to Bob's question how did this thing work?. The image shows no boards, no cutter, no obvious attachment points for these?
Why would these be added later after installation on the ship? Also Bob photo shows no trace of boards or the braces or the cutter you would expect at the nose?
:nerd:
Without the boards it wont pull a wire out to the side of the ship? its impossible? how does it cut a mine wire if it cant pull a wire out?

Is this a central weighted stabiliser and there would be two paravanes each side? as Sean's classic images? But why go to the trouble of making that complex tail?

This sketch of a tow-behind sweep (from Wiki) shows a component called a "depressor"

https://upload.wikimedia.org/wikipedia/commons/thumb/1/13/Minesweeper_cutting_loose_moored_mines_diagram_195 2.jpg/220px-Minesweeper_cutting_loose_moored_mines_diagram_195 2.jpg

Could that be what we're looking at? Although I suspect the Wiki picture is slightly inaccurate, as I guess one would always want to run the sweep from the bow for obvious reasons!

There's a German modeller here (http://www.ship-model-today.de/sd130.htm) who goes into some detail about minesweeping. However, my technical German isn't good enough to follow this (at least, not quickly). The pictures he includes are samples from the full set of plans, which can be ordered from http://www.ship-model-today.de/schiffsdetails.htm (The relevant set of plans is sd130).

There are also reference texts listed if anyone has access to these (perhaps through a university library?)

[matt]

Could that be what we're looking at? Although I suspect the Wiki picture is slightly inaccurate, as I guess one would always want to run the sweep from the bow for obvious reasons!

There's a German modeller here (http://www.ship-model-today.de/sd130.htm) who goes into some detail about minesweeping. However, my technical German isn't good enough to follow this (at least, not quickly). The pictures he includes are samples from the full set of plans, which can be ordered from http://www.ship-model-today.de/schiffsdetails.htm (The relevant set of plans is sd130).

There are also reference texts listed if anyone has access to these (perhaps through a university library?)

Interesting that the same (wrong) picture also appears in that thread!

[Paul Evans]

an image search on "raumaotter"

http://parow-info.de/f/krake/h-gbt.gif

source http://parow-info.de/f/fb/habicht.html

the image is behind a link half way down the page
klappspiere am vorsteven für bugschutz mit räumotter o.r.g. Und / oder mit geräuschboje-turbine g.b.t auch

i don't speak german but "geräusch" appears to translate something like to "noise" and "boje" is "buoy"

so. I guess it's a para-vane with an underwater siren, for targeting acoustic mines.


WARPUS ;) or at least the German version :nerd:

When I saw the cowling I thought there was a turbine in there !!! And the box at the front is the hammer box..........

:8):

Matt S Top man ;)

[Paul Evans]

Did you know that the original British Hammer box was powered by a KANGO, the very same one used to dig up road's? And the original anti mine hammer box was nicknamed the Kango :nerd: Kango was a British company back then? may still be but i doubt it !!!

[Paul Evans]

DP.......................

[Iain Smith]

Interesting that the same (wrong) picture also appears in that thread!

Got it. It's a Geräuschboje-Turbine
https://upload.wikimedia.org/wikipedia/commons/9/92/Ger%C3%A4uschboje_GBT.JPG

Apparently the rectangular head makes it a GBT-II

It had something to do with clearing acoustic mines...

[Iain Smith]

Here we see a pair of them stowed at the bow:

http://forum.axishistory.com/download/file.php?id=294146&sid=b9a8ac3abba4db1479c7466c116040da&mode=view

[Iain Smith]

OK - I think this picture is of a GBT-I:

http://forum.axishistory.com/download/file.php?id=294184&sid=b9a8ac3abba4db1479c7466c116040da&mode=view

It appears as though these were "noise-makers" - intended to detonate acoustic mines at a safe distance from the ship.

This is how the GBT-II shown in the previous post would deploy

http://forum.axishistory.com/download/file.php?id=294185&sid=b9a8ac3abba4db1479c7466c116040da

Source is apparently Meyer's Hochsee Minensuchboote

[Paul Evans]

Here we see a pair of them stowed at the bow:

http://forum.axishistory.com/download/file.php?id=294146&sid=b9a8ac3abba4db1479c7466c116040da&mode=view

Translated from Wiki.........

The clearing of mines that are responsive to the typical noise of ships is done by nachgeschleppte float with a sound source to trigger the mines. Originally, the sounds were mechanically generated by a generator driven by the drive flow propeller at the end of the float inside which operated a "clapper work", which was adjusted so that it could produce different, typical for ships, frequencies (jokingly called "Give Toni")

[Iain Smith]

Ah...lots of cross-posting!

[Paul Evans]

The square box on the front you could compare to the case of a sub woofer, with the actual source device inside it. The steel faces radiate and probably amplify the sounds under water......??

I haven't been able to find pictures of a British Warpus or a early hammerbox to compare :(

[matt]

I think Iain wins :-)

I found this whilst looking about which I found interesting about the Sperrbrecher (half way down, in French): http://www.grieme.org/pages/gauss.html

http://www.grieme.org/img/gauss7.jpg

[Bobanderson]

good work guys, thank you very much..

[matt]

good work guys, thank you very much..

Interesting thread. Do you need any tips on boiler repairs....lol.

[Paul Evans]

OK all

WARPUS

http://www.mcdoa.org.uk/development_of_minewarfare.htm

""The British tested a hydraulic siren as an acoustic device early in the Second World War but the results were less than promising. At the same time , the Germans had produced a towed hydraulic siren. A US Navy project was started in 1945 to test a siren against acoustic mines. This version proved successful. It was compact and used a portable fire pump to push water out a tubular stator broken up by the rotation of a cup turned with compressed air. Because of the use of water and air it became know as 'water air powered underwater siren' or WAPUS for short. Interestingly, later improvements made it possible to eliminate the compressed air supply but the name remained.""

I cant find anything else, no pic's, nothing??

Anybody got any idea's?

[Iain Smith]

OK all

WARPUS

http://www.mcdoa.org.uk/development_of_minewarfare.htm

""The British tested a hydraulic siren as an acoustic device early in the Second World War but the results were less than promising. At the same time , the Germans had produced a towed hydraulic siren. A US Navy project was started in 1945 to test a siren against acoustic mines. This version proved successful. It was compact and used a portable fire pump to push water out a tubular stator broken up by the rotation of a cup turned with compressed air. Because of the use of water and air it became know as 'water air powered underwater siren' or WAPUS for short. Interestingly, later improvements made it possible to eliminate the compressed air supply but the name remained.""

I cant find anything else, no pic's, nothing??

Anybody got any idea's?

I have a contact who may have access to some historical material on mine warfare. Not sure when he will get a chance to look, but will pass this on.