Windward ability of different rigs

[WX]

After the discussion in the Gaff verses Lug rig thread I thought I would check with Junk rig owners to see if my figures were accurate. 45% close hauled is about right for Cambered Junk rig. Arne can get it down to about 85 degrees. Now this doesn't seem much to some but it seems unless you are sailing a racing boat then this figure of 45 degrees is not that bad. Here is some further info that has come my way.

Typical angles to the true wind are as follows. Actual course over the water
will be worse due to leeway.

- about 35° for modern racing yachts which have been optimized for upwind
performance (like America's
Cup http://en.wikipedia.org/wiki/America%27s_Cup>yachts)

- about 42 to 45° for modern cruiser-racer yachts (fast cruising yachts)
- about 50 to 60° for cruisers with an emphasis on interior space, ease
of handling and often low draught rather than sailing performance, and for
boats carrying two or more masts (since the forward sails adversely affect
the aft sails when sailing upwind)
- close to 90° for square riggers and similar vessels due to the sail
shape which is very ineffective when sailing upwind

So how about some discussion on the various rigs. What have you had experience with and realisticily , how close could you pinch it and still have good speed though the water?
be honest now.:)

[Paul Pless]

be honest now.:)

http://i.treehugger.com/images/2007-2-21/Windmill-Sailboat.jpg

[WX]

trust you to be contrary Paul.:)

[huisjen]

That's gotta be photoshop. Please tell me that's photoshop.

Dan

[Brian Palmer]

Our Elver canoe yawl (jib and sprit main on a free-standing mast, standing lug mizzen) can tack through 90 degrees (sail 45 degrees off the wind).

Brian

[wizbang 13]

My ol,12ton,30'wl.gaff tub might do 90 between tacks. If the water is flat,the wind is good ,the botton is clean and I am happy with 3 1/2 knots.Usually zero of these conditions exist so I crack off to 120 and" giddy up "to a whopping 5 1/2 k!! That being said, the only junk to pass me upwind was "Brysan" which I think is a well known boat (and 10' longer)

[huisjen]

I've got something I'm playing with in my CAD program. This is sliding gunter, full battens. I know people may knock holes in it, but that's the point of putting it up here. I wonder how this kind of rig would handle. The grid is 1' boxes.

http://img.photobucket.com/albums/v219/huisjen/schooner.jpg

Dan

[wizbang 13]

....But I guess most here are interested in small boats, my converted to gaff Kutter (23') goes both close and fast. Even with the funky homemade sails. It's a pleasure to finally have a gaffer that can, on ocassion, beat a macaroni upwind.

[bott]

Keep in mind that, regardless of the rig itself (given its ability to create lift at various angles of attack), the cut/shape of the sails is of major importance. If the sails have a fuller cut and a naturally forward-placed draft, the air moving over them at higher speeds (like going upwind) will stall (luff) sooner than a sail with a flatter entry.

There is *so much* more involved than then just the name of the rig in sailing performance. The other major one being, how is the rig suited to the hull its being stuck on? Sailboats are basically two wings (sails and keel) balancing between a air/water boundary, and they should act in harmony. You don't want to put a Ferrari engine into a dump truck, nor vice-versa.

[huisjen]

Say what about Ferrari?

http://www.saltcreekgrowers.com/008a.jpg

Dan

[Paul Pless]

That's gotta be photoshop. Please tell me that's photoshop.

Dannot photoshopped

[Dr.Spoke]

In flat water, I'll get 40 degrees from the wind with my Ljungström rig. In any kind of sea I'll opt for "fast-and-free" to help through the waves. At 40 degrees the she'll struggle to top 4 knots, at 45-48 degrees she tops out at (about) 7.4 knots ( yes I've tested this carefully with a GPS in non-tidal waters!)... Not so fast, but she's only 6.6m overall!

[Woxbox]

- close to 90° for square riggers and similar vessels due to the sail
shape which is very ineffective when sailing upwind

I've seen this claim many times, and it just isn't true. The Kalmar Nyckel is a 17th century replica, a full-rigged ship of the period, and she can sail to windward and tack reliably. And that was before a couple of hundred years of work to improve the type.

Here she is trimmed for windward work. Note the angles of the yards and how straight the leading edge of the fore and main courses are. The sails are square, but can be hardened up to get the belly out of them when desired. She can and does point trimmed like this. I'd love to have a photo of her bashing to windward in a blow, but on days like that the dinghy is never dropped for photography.

http://i45.photobucket.com/albums/f92/Woxbox/KalmarNyckel.jpg

[P.I. Stazzer-Newt]

That's gotta be photoshop. Please tell me that's photoshop.

Dan

That might be, this isn't:
http://www.pooleredwings.co.uk/images/auto7.gif

http://www.pooleredwings.co.uk/redwing_history.html

[David W Pratt]

Truth has tacked through 85 deg in flat water and 7-10 kts of wind.
Another huge influence on weatherliness is the ability of the boat to stand up to her canvas. Marconi rigs with half rolled up genoas suffer a terrible lift:drag ratio from the baggy sail leading to lots of heel, lots of leeway and abyssmal windward performance.

[huisjen]

Okay, here's another consideration. They say that you want flat sails in heavy wind, full sails in light wind. What if I have big flat sails in light wind. I recognize that my proposed rig may be a bit oversized for the boat in question, but it'll be very easy with full battens and lazy jacks to drop the bottom panel down and give it a first reef when looking at even moderate winds. What say ye? Full, or just big?

Dan

[John B]

Gary , its almost impossible to quantify because there are so many variables. Already we've got two languages being used in just discussing the degrees off the wind.( 45 degree true wind angle V 90 degree tacks and 90 degree true wind angle ie 180 degree tacks) god forbid.. it'll be apparent wind next.
Also what happens is that how 'good' or how well a boat points is completely relative to who is doing the talking.A pig to windward in racing circles is quite probably a perfectly adequate cruiser.

But some generalities...... Waione sailed almost exactly the same angle to windward under gaff new sails as under bermudan new sails.. ie she 'd hit her hull capability to go to windward. She had more sail area gaff so she went faster in similar conditions.( that showed in lighter air performance obviously)
Riada with her ketch rig? better to windward with the mizzen down after 20 knots and not as good to windward as a sloop in racing conditions. Extra masts in a line cause drag and a closing wind angle if that makes sense, so a mizzen needs to be flatter than a foresail/ main which is flatter than a genoa or jib combination.
Flat sails in general? well modern race boats carry very flat sails compared to even 10 years ago, and their genoa leads are often sheeted incredibly close. Where the norm on an old IOR boat might have been 11 or 12 degrees.. these guys are barber hauling in 6? So that tells you how expectations have lifted along with hull design and construction , sail materials, rig materials etc.,. and comes back to botts point about a rig fit for purpose ... compatibility with the hull its going on.

[WX]

I realise there are many variables that can and do affect the sailing ability of a vessel. I am sure we could go many pages if we were to get into theory, however what I am interested in is what people are actually getting in practice. from what I have read it seems 45 degrees off the wind is not bad going for a cruising yacht.

[John B]

It is in practise . Waione sailed the same angle to windward under bermudan as she does gaff.
Riada doesn't go as well to windward as a sloop but she's close.I have lousy wind gear and don't get true wind direction. Apparent wind changes with wind velocity so its hard to get an accurate idea back to true.
My expectation is to look at my gps track and see 90 degree or better angles when tacking.

[Woxbox]

If I can get regular 90 degree angles on the GPS readout in any boat, I'm happy with that. Once in awhile a favorable current will make it easy, but usually things work against nice predictable headway. My current boat, a catamaran, has short stubby keels that need a certain amount of speed before they grab. So in light air, the compass says I'm 45 degree off the wind, but the GPS belies that notion. It takes attentive helmsmanship, too, to maximize windward performance. Start to gab with the crew in the cockpit, and it's easy to lose 10 degrees or more. Choppy water? More leeway, and so on.

[Todd Bradshaw]

Dan, It's more like flat sails in heavy wind, fuller sails in moderate wind and back to flatter sails in light wind. The reason being that light air doesn't tend to stay attached and follow a deep curve as well, leading to stalling.

The other thing that must be considered is the hull they're driving. Broad, heavy hulls need more power to get them moving and drive them through a chop than skinnier, lighter hulls do. Power is generally created by deeper draft. Fast acceleration and high top end speeds for light, sleek boats, on the other hand, are generally created with fairly flat sails (think beach cats or iceboats). A flat sail on a heavy boat is pretty likely to be underpowered and may never get into boatspeed ranges where it's doing what it does best. Or....stick a deep draft, high-power sail on something light and easily-driven and it will tend to overpower the hull and never be able to really get the hull up into it's potential speed range. In both cases, it just may not be the right type of draft for the job at hand.

Your gunters (they're actually folders, not sliders) have almost half of their sail area in the roaches. In a best case scenario, that type of big-roach sail would do best on a boat that was a fast reacher (like a multihull or some other type of speed sled - Melges 24, Ultimate 20, planing dinghy....that sort of hull). They're often much less effective on cruising-style monohulls, contributing more to heeling than anything else. Without some pretty serious design work on the sails' entry curves and battens, they may also tend to have pretty flat entries. That can make a cruising boat very tedious to steer and quite intolerant of minor trimming/steering errors.

[Jay Greer]

In his 1905 book "Tales of the Fish Patrol" Jack London, who was working for California Fish and Game relates how the Chinese fishing junks of that time could out point is gaff sloop rigged patrol boat the "Raindeer".
Jay

[WX]

The Portuguese married a Western hull with a Junk rig back in the 17th century and called it a Lorcha.

http://www.thepirateking.com/images/ships_lorcha.jpg

[purri]

Lateen rig is quite efficient!

[WX]

Lateen rig is quite efficient!

How efficient? better than 45 degrees off the wind? How about before the wind round to broad reach?
Bermudan rigs have chased windward efficiency to such an extent that it is now their only good point. They are in fact a labour intensive rig.

[seanz]

The Portuguese married a Western hull with a Junk rig back in the 17th century and called it a Lorcha.

http://www.thepirateking.com/images/ships_lorcha.jpg

They did a bit more than that. They seem to have developed the rig a bit too, I've seen images of Lorchas with jibs and bowsprit.

There are some cool (well, I think so) modern versions as well, somewhere I have a picture I nicked from the interwebs of a Colvin Gazelle.....junk-rigged schooner with jib and fisherman staysail.

[seanz]

Good, there's a couple of pics out there.....

http://www.sommerstravels.com/?page_id=2

There's even one on Wikipedia....

http://en.wikipedia.org/wiki/Junk_Rig

....they have everything.

[PeterSibley]

How about a definition of efficiency that includes price in the formula ? Something like dollar per watt in energy generation .The high tech windward machines might have a substantial handicap to overcome .

[Andrew Craig-Bennett]

A terribly boring point I know but we need to compare apples with apples. In particular as all racing sailors know a small difference in, say, windage can be "multiplied" by the losses involved in going to windward.

It used to be said that the Redwing class had pretty much settled the issue, since their class rule specifies a one design hull with 200sq ft set over it in any manner.

[PeterSibley]

Did any unusual rigs get tried Andrew ,modified lateen or similar ? I read a fairly complete comparison a while ago in one of my older magazines (which one ? no idea of course ! ),an FAO comparison ,using a fairly horrible fishing boat hull as the base .Lateen rated well IIRC .

[Andrew Craig-Bennett]

I think that there were a fairly complete assortment of oddities at the outset, and that later ideas included a windmill and the Ljungstrom rig. It would be fair to say that technology has improved, so the friction that crippled the windmill rig would not do so now.

[Oyvind Snibsoer]

According to Marchaj, the most efficient off all rigs is the "primitive" crab claw.


"Even more startling is the extraordinary performance of the crab claw sail, which demonstrates its superiority to a Bermuda mainsail right from the close-hauled condition. Its superiority increases when the boat bears away, and on reaching, with the heading angle 90 degrees, the driving force coefficient of the crab claw is about 1.7, whereas that of the Bermuda rig is about 0.9. That is, the crab claw rig delivers about 90% more driving power than the Bermuda rig."


More here: http://www.proafile.com/view/weblog/comments/rig_options_crab_claw/

[PeterSibley]

Crab's claw ...yes ,definitely one of the better ones .

[James McMullen]

I don't know what's the very best, but after being raised on a steady diet of sloops in my mis-spent youth, I was shocked and then delighted with the performance of the lug in that first Ness Yawl I had built. I would have been satisfied with less because of the other beneficial aspects of the rig with regards to handiness, but she really surprised me. My own latest iteration of the rig with better sail-shaping adjustment tackle and more carefully shaped foils on the boat itself has been a simply sparkling performer--especially when you consider she is just a big rowboat. I will regularly point higher and sail closer than the typical indifferently handled bermudan rigged cruising sailboat round here. Something like an Etchells can walk away from me, but I have delighted in sailing rings around boats like a MacGregor 26, taunting them for being ugly as well as slow all the while.

http://inlinethumb15.webshots.com/42254/2475785700088484686S600x600Q85.jpg (http://sports.webshots.com/photo/2475785700088484686LWCItB)

[ARW123]

They say a Norfolk Trading Wherry is one of the highest pointing vessels about :-

http://farm2.static.flickr.com/1267/1118759924_316b77d0ff_b.jpg

[WX]

Good, there's a couple of pics out there.....

[/URL]
There's even one on Wikipedia....

[URL]http://en.wikipedia.org/wiki/Junk_Rig (http://www.sommerstravels.com/?page_id=2)

....they have everything.
The Wiki site needs a bit of updating. The work done by Arne Kverneland into cambered sails has taken the Western Junk rig to a whole new level of windward efficiency that now puts it on equal footing with virtually any cruising rig.
Slieve McGalliard's work on the Split rig may well give us the first racing Junk rig.