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  #1  
Old 01-23-2006, 04:54 PM
JohnTReed JohnTReed is offline
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Steading Sail for Trawler

I had a sail boat for 23 years and have been cruising for the last 4 years. We have returned and sold our sail boat and bought a Marine Trader Trawler. I would like to put on a steading sail to cut down on the roll. I cannot find any information on how it has been done on other trawlers or if it has ever been done. If any one has information I would be very much like to have it.
Thanks in advance for any help
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  #2  
Old 01-24-2006, 10:08 AM
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Eric Sponberg Eric Sponberg is offline
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Bob Beebe in his book "Voyaging Under Power" discusses steadying sails briefly, but ultimately opts for flopper-stoppers. In my opinion, flopper-stoppers work, but they do have considerable drag, and it's a lot of hamper to have over the side, particularly if you happen to get caught in restricted areas, such as channels or in amongst lots of other boats.

I like steadying sails--you use them when you need them, when it is a little windy and the seas kick up--and you want to steady the boat.

There was a nice article in Passagemaker magazine in the Sept/Oct 2004 issue, pg. 92, called "Got Sails?--A trawler with sails: exciting, efficient and enjoyable." by Robert Lane, one of their contributing editors. You can contact the magazine through www.passagemaker.com, or call them at 410-990-9086 in Annapolis, MD or order back issues.

Eric
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Old 01-24-2006, 01:12 PM
JohnTReed JohnTReed is offline
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Thanks for the information. I ordered a back copy. I agree with you about the convience of sail. I believe I can rig a roller furling. I will add sheets and blocks for trimming the sail. I am new to power boating and do not understand why aren't there more trawlers with sails? The people on the dock think I have lost it talking about putting sails on a trawler. Again Thanks.
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Old 01-24-2006, 02:18 PM
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safewalrus safewalrus is offline
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many years ago drifters and longliners had small mizzen sails to steady the vessel when lying to their nets/lines (in European waters). Danish boats still do! the reason trawlers did not use steadying sails was the fact that with a large 'bag' being dragged along the seabed this acted as a steadying device itself!

Of course the old fishing vessels of Europe, having developed directly from sailing vessels were more seakindly that the average square box like thing that passes for a trawler these days, especially ones used for yachts which have only passing resemblance to fishing boats on this side of the Atlantic!

the main reason that fishing vessels these day don't use steadying sails is the fact that with the big powerful engines they just turn into the weather and dodge - not like the old days when there wasn't much choice (mind you half a mile of drift net made a lovely sea anchor)!

However when it comes down to it I do not see why a small mizzen should not be fitted on the back of a 'trawler' as a steadying sail, after all 'flopper stoppers' are only really of use whilst at anchor! Might even be of use as 'a get you home sail' as long as you don't overdo it! Don't forget you'll make a fair amount of leeway with the modern trawler yacht with a fair sized sail (if you don't turn the damn thing over - whoops)
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Old 01-24-2006, 03:39 PM
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Eric Sponberg Eric Sponberg is offline
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The flopper stoppers that Beebe talks about in his book are actually paravanes, and they are deployed while running. The other common flopper stoppers, as seen on the west coast, are indeed used only at anchor.

Incidentally, there are two other Passagemaker articles that may be of interest:

Nov/Dec 2001, Dreamworld Stabilized, about the design and installation of paravanes, a case study.

Nov/Dec 2002, The Eternal Debate, Power vs. Sail, people's opinions on which is the better way to go.

Eric
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Old 01-24-2006, 09:22 PM
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Tad Tad is offline
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John,

Recently there was considerable discussion of the steadying sail for small trawler yachts on the Trawlers and Trawlering list. Some folks did testing with the sail up and down, and all who have steadying sails say they help damp out rolling at all times, even if there is little wind.

These sails are small, approximately 120-150 square feet. This is small enough that you can almost forget about them in most situations. If it's blowing half a gale, you'll have to get it down to gain control of the boat, but normally you set it and forget it. Some folks, I think it was a round bottomed Willard, reported 5-10 degrees of heel in a cross wind, but the boat was quite stable with no rolling to windward.

I have used large steadying sails on longliners, and the main reason for their use there is to cock the boat up into the wind to haul gear. But they are stunningly effective across the wind, with the boat moving vertically but not rolling.

I've always argued against a steadying sail for roll reduction because powerboats will rarely (never on this coast) find a good breeze blowing on the beam. And as you increase speed, the apparent wind moves forward, again reducing the effectiveness for roll reduction. This discussion changed my mind and for some folks the small steadying sail is a solution to scary rolling.

Next concern is cost/effectiveness, a well supported mast is probably necessary for either a steadying sail or paravanes, strong shrouds and chain plates will be required. The paravanes are much more effective at roll reduction, but at the cost of drag. The hydrodynamic drag of paravanes will be much higher that the windage of a small steadying rig.

I have an idea your boat is hard chined? This type tends toward snappy rolling, the steadying sail will damp that out a bit. The rig and its fittings must be strong to deal with the forces involved in heeling your boat in a 20+ knot breeze.

All the best, Tad
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  #7  
Old 01-25-2006, 02:49 PM
JohnTReed JohnTReed is offline
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Thank you for your responce. There is a mast already stepped and has shrouds connected to chain plates. The reason for adjustable main sheets is so that I can control the sail placement and shape. By using a roller furling I will be able to reef the main as the wind builds.

As in a sail boat I will need to be aware of my point of sail in relation to the sea. When going down wind I would only set the sail out far enough to keep it full. Hard into the wind I would motor a little off the wind in order to keep the sail full and tack when necessary. I would reef to eliminate any type of heeling.

I understand that this sailing approach may be only a pipe dream on my part but when I looked at active stablizer costs, ($25,000 to $35,000) or paravanes at ($7,000 to $15,000) a roller furler and assorsited hardeware costs ($1,500 to $3,000) it seemed worth a try.

By the way, while looking for some type of design help for the development of the rig I ran across an Idea for down wind. You probably have seen the sail board kites, (big sail up in the air pulling a person on a surf board). Down if Flordia there is a company that will make the sail kite for pulling a boat. I might look at trying that as a way for getting home. My boat only has a single diesel.

Thanks again
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