Interesting "Flopper Stopper" Setup

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THD

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[/ATTACH]Saw a boat on our transient dock this morning, a Nordhavn, 46' I think. I noticed "Flopper Stopper" mounted on the transom. But, there were no big vertical support poles to deploy them. I looked more closely and there were spars mounted just under the lip of the boat deck. They were about 12-15 feet long. Hinges mounted on the cabin exterior. I could see how the system worked in theory, but just could not see it in practice. A few pics:

First are the fish mounted on the transom.
Second is the portside spar.
Third is the hinge mounted on the cabin exterior
Fourth is the starboard spar.

A couple of issues stood out to me. I did not get a shot of the end of the spars, but there was a tang at the end with four points for attachment. Presumably one for a vertical wire, one for a forward and one for a stern support wire and one for the line to the fish. I looked up and down the side of the boat and could not see any apparent attachment points for the fore/aft support wires. I presume there was some attachment points on the mast for the vertical support wires. Also, the hinge allows only for horizontal, i.e. fore and aft, movement, not vertical movement of the spar once deployed. Seems like there would be a lot of potential stress put on the cabin hinge point once the fish are deployed. How strong is that hinge mount? Last, the cabin is full width, no walk around. Once deployed, the only access to the spars is from above on the boat deck. Any line to the fish would have to be led back to the back deck, some 12 feet or so astern of the spar when deployed.

Not too shire I would want to be tryng to set up and deploy the fish in thei system in any kind of a sea.

Anyone else seen any setup like this?
 

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Damn! Rotation problems! How do I correct this?
 
Hard to tell from the photo orientation but could those just be storage options for when not in season/use? I don't see how, at least the poles, could otherwise be functional in that arrangement.
 

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Those "fish" primarily are used for paravanes not for at rest rocker stoppers. The poles(s) pictures, look like the ones sold by Forspar, designed for at rest. There are fore and aft lines plus a topping lift that you don't see in the picture. This was (maybe still is) an option that Nordhavn offers for at anchor roll stabilizers. The fish surprises me though, since Magma makes a much better roll stabilizer than the one pictured.
 
Larry-the spars were indeed Forespar, could see the label. As you noted, the fish are paravane, not at rest, style. If the system is just an at rest system, I would have expected something akin to the Magma.
 
As a salmon troller we used the paravanes when fishing to slow the roll of the boat.
When anchored they also controlled the roll.

Ted
 
The pole if swung outboard from that location, with fore and aft lines and a topping lift supporting it would be under a compression load.

The paravane would pull down and the topping lift would transfer most of that load to it's upper attachment point.

The drag from the paravane would put an aft load which would mostly be transferred to the forward line.

Some of both those loads would become compression load that the pole would transmit to the cabin side.

The aft line would rarely have a load on it while the boat was underway.

If everything is sized correctly, it looks like a nice installation to me.

The pivot joint looks like it would allow the pole to swing both horizontally and vertically.
 
The eagle had poles along the roof of the salon used mainly at anchor. Like the ones in the picture, however they did not look strong enough. I took them off and installed gutters instead so the rain water was drain directly over the side. I been looking and thinking of installing flopper again, but for our warm weather in side cruise have not found the need. I still have the fish and poles, and installed a new heavier mast for when the time comes. However I would install with the poles vertical and rigged ready to be deployed.
 
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