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Cat-Ketch vs. Cat-Yawl


motscg

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Ok folks, having elicited a great discussion on boom vs sprit-boom rigs (in the B&B Forum), I would like to hear opinions on sailing a cat-yawl (i.e. Chebacco 20) or Canoe-Yawl (Rob-Roy 23) vs a cat-ketch (i.e. Princess Sharpie 22 or Sea Pearl 21).

I understand the differences between a yawl and a ketch (i.e. mizzen position and sail size), and I realize that there are some common characteristics like using the mizzen to help balance the boat, but I am interested in hearing opinions on the sailing differences, peoples preferences, and why.

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Thanks Ray for pointing out some of the strengths of each sail plan. Just wondering what some of the various experiences people have had sailing both types. Did one stand out over the other - or is it simply preference, but if so, why that preference. For example, is there strong sentiment for the extra drive of the ketch mizzen over the yawl mizzen at the expense of having the clearer cockpit of the yawl or other yawl factors? Which is easier to single-hand or are they pretty much take the same effort? etc.

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George Ray has a lot of wisdom on these rigs, but as usual I have to put in my two cents worth. IF every one liked just one of these rigs there would only be one. You know, different strokes for different folks the old man said as he kissed the cow under the tail. Y'all Come Cap'N Bud. :wink:

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The Rob Roy 23 and Chebacco 20, are very different boats, so comparison is difficult. The Rob Roy is literally 2 1/4 times the boat a Chebacco is at 2800 pounds verses 1200 in displacement (respectively). Also the Rob Roy carries 32% of it's displacement in ballast against zip in Bolger's little cruiser. The Chebacco is not much more then a dinghy (certainly handles like one) where the Rob Roy is a more substantial craft.

These are typical problems when trying to compare different boats. Each boat has a set of design parameters, usually being sufficiently diverse to set them apart from one another.

It's generally correct to say, that most designers try to develop a craft that will sail and balance well. Unless you have some specific requirements, most rigs will get you along fine, some with aspects not found in others.

The traditionally proportioned ketch rig is about as balanced a rig as is available. It shortens down evenly, unlike most rigs and has multiple hoist options, though this is true of most divided rigs. It isn't as close winded as the single stickers, but more then enough for most cruising.

The cat versions of the yawl and ketch move the poles forward along the LWL, which can free up the cockpit in a ketch. Direct differences would be the mizzen mule being smaller on the yawl, but the yawl's taller luff will permit slightly better windward ability. The yawl will have a more open cockpit, with the mast typically at it's aft end. The cat ketch mast locations are similar to that of a schooner with the mizzen placed at the front of the cockpit. In small boats this is all relative as the whole of the boat is usually "cockpit", maybe with a small foredeck or aftdeck.

I have to admit a romantic affection toward traditional yawls. They really came into fashion when ocean racing, rating rules favored their use. Everyone that had a sloop, converted to a yawl to take advantage of this, and my youth is filled with fond memories of the rig. I've owned several CCA style yachts (the best ocean cruiser in my opinion) all yawls (like most of them were then), they were well founded, comfortable, weatherly, safe and fast craft. I learned to back a 35' Arthur Robb design (1965 CCA style) out of it's slip with the mizzen, because I was to poor to rebuild the dead Atomic 4 that lurked in the bilge. As a ketch (which was an alternate rig) the mizzen would have been in the center of the cockpit, making it not as inviting a place to hang out. As a cat ketch, the mizzen would have been against the cabin bulkhead and an offset companion way hatch would have been necessary, which would have been difficult on a boat with a 9' beam, that liked to sail on it's ear.

As the vast majority of things in yacht design seem, compromises are made, many of them and no definitive solution or comparison can really be attempted. After accessing your needs in a sailing craft, making a list (or several) of the things you find most - to least important to you, some things will stand higher in priority. Select the craft/rig that most closely suits your desires.

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Thanks for offering your perspective on the differences (I actually tried to respond earlier, but with interruptions, I took too long writing and when I hit the submit key I found that my session was timed out and what I wrote had gone poof! :( .

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A mast section can be devised to be completely free standing (without stays or shrouds). It's not uncommon, nor will it add to the complexity of the build. All stayless rigs are easy to setup.

A traditional ketch will balance better then all other rigs, if properly proportioned (jib and mizzen being nearly equal in area). The cat versions of both rigs will fall into their own peculiarities (yawl to windward and ketch off wind).

Having the centerboard case below the cabin/cockpit sole will increase the draft and possibly limit you to a "Slice off pie" style of board, which isn't as efficient as a higher aspect version (more commonly seen on modern designs). A keel stub, housing part of it will help some. A pop-top is a good compromise for headroom and can have a screen added to it for nicely ventilated, overnight accommodations.

As you gain sailing experience, all rigs show the sailor what it likes (and doesn't). It's natural to make adjustments, probably being unaware you're doing so, and adapt to what your boat desires for a good sail set, holding course, best speed, tacking technique, etc. Moving from one boat to the other, will illustrate this clearly, but we rarely have opportunity to do this.

A stiff boat, for guests, is usually a poor sailor. There are only a few ways to get this stiffness and they involve insufficient sail area (and/or CE height), firm bilges, excessive beam, high ballast/displacement ratios (which means a light weight hull, for a trailer sailor).

When I was teaching in a sail training program, in St. Pete years ago, I found developing confidence much more important then a stiff yacht. I would have them brace, some even grabbing lines and foot ropes. Then I would make the boat heel way over, which initially caused considerable concern among them. I would read the moment (and the fear in their eyes) and hold it, rail down, as I casually went about talking, leaning over the side, "checking water temperature", etc. The whole time trying to build a little confidence in the boat, talking about angles of positive stability (which they cover in the classroom work, but always forget when scared) and pointing to the heel angle gauge on the bulkhead. Then I'd ease the boat back up and luff up for a quick chat, pointing the highest angle we'd reached (approximately) on the gauge and noting we had several dozen more degrees of stability before the boat would have flopped over. Next would be a nice easy broad off course, to get their heart rates back below 100 and sure enough, more times then not, they'd want to try that heeling thingie again, but "not too much, okay?". This was usually followed with a gradual tightening on the sheets and honest answers to question about their "real" fears. Followed by "you'd have to have the Jolly Green Giant, tossing you with a huge spatula, to flip this boat" kind of rhetoric, which built up faith. More experience will do the rest, usually.

The wise skipper recognizes this early on with newbes and handles it, by inspiring confidence in their newly earned skills, understanding the integrity of the boat and instilling faith that the world was discovered by boats that were motivated by the same propulsion method, most of which didn't have particularly notable stability curves.

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PAR,

Beautiful piece of advice, especially regarding novices and comfort with heel. I must profess my surprise at my own discomfort when I first encountered sailboat heel. This despite being a Master Mariner that has rolled his guts out for many years on the North Sea. When the boat did not come back but just stayed heeled over it just felt weird!

Now I love to sail my 13' clinker style fiberglass dinghy with a Laser 1 main cat rig. That is a lot of sail and with anything nearing 10 kts of wind is a handful since it does not plane. It has taken a few sails but slowly my wife is getting more comfortable with the motion of boats in general.

Michael

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Hi guys,

Hope this isn't too far off topic, but the yawl vs. ketch issue made me start wondering about sail proportions vs. performance.

The yawls I've seen have a small mizzen with a large main (I think I read somewhere the mizzen is usually less than 20% of the main on a typical yawl--call it a 15/85 split). The ketches I've seen appear to have both mizzen and main roughly equal in size (50/50). Is there any reason a fellow wouldn't want to strike some middle compromise? (Dividing sail area 66/33, for example.) Does anyone know how the proportions of split rigs like yawls and ketches affect performance... or is it a moot point as long as the sail area is properly balanced with the CB?

The reason I ask: I was toying with redrawing Parker's 27' x 6' New Haven sharpie as a cat ketch (not for any good reason... just to learn how to calculate CE for a split rig). The original sailplan is for a single sail, approx. 152 sq. ft. with an optional "light air jib" adding another 52 sq. ft. I redrew her with a ketch sailplan, with the mizzen 86 sq. ft. and the foresail 121 sq. ft. for a total sail area of 208 sq. ft. The ketch sailplan lowers the center of effort by 12 inches, and replaces the single 26' mast with a 23' foremast and 21'3" mizzenmast. My thinking for making the foresail 50% larger than the mizzen was to increase reefing options. If the boat were fitted with a third (centered) mast-step, you could switch from full sail (208), down to foresail alone (121) down to mizzen alone (86). Anyway, I'm wondering if there is some reason it would be a bad idea to split the rig 58/42 like this... would it throw off balance?

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George, my understanding of the heeling business is this: ballasted round-hulled "tender" boats perform best when heeled--which they want to do anyway since the round hull allows it and the ballast has increasing righting moment as heel angle increases (referred to as "low initial stability" but "high final stability"). The Core Sound boats, by contrast, are unballasted, and stiff ("high initial stability") because of their relatively flat bottoms and hard chines. These boats are mean to be sailed relatively flat and perform best that way. I hear you on the issue of keeping crew and passengers happy: some of my more high-strung family members get nervous, also. They may know intellectually that they're safe, but that's not what their gut is telling them!

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George, my intent wasn't to tell you how to cope with your sailing friends and family, but just to offer suggestions how I've done it. I've never forced anyone to accept heel angles they weren't ready for, or that I wasn't willing to reduce for their benefit. Yes, some paid to learn, but I never have been comfortable asking folks to "suck it up". I usually did just the opposite, trying to find a point of sail they could settle into as they got some "legs" and confidence. I've also had many more individuals aboard a sailboat for the first time, whom hadn't paid. I simply watch them, how they react, how much color was running from their faces, etc.

I learned this the hard way, when I took out my first wife for her first sail in a very fast planning screamer on a blustery day. She couldn't swim well, which of course made her very nervous, more so as we got father from shore, she wasn't confidant of her hand strength and the whole heeling thing was enough to have her filing for divorce shortly after landing back on the dock. I was young, scared the hell out of her and never quite forgave myself for such a foolish (and selfish) blunder.

Sailing is a very intuitive thing, most take to it quickly, some longer and a few I've known, never did despite their many attempts. My previous post wasn't an attempt offer training tips to your family, just an offering on my casual approach. If that post offended you, it surly wasn't my desire to do such, but if it did, please accept my apologies. I've repeatedly found that humor and a relaxed style worked the best for me, to sooth the discomfort levels of new to sailing people. I don't think I've exposed others to these traits some captains own. At least in my experience no one has said so.

Sailing with little to no heel in a mono hull craft (not on plane) is difficult. It's the nature of the beast and what makes them go. There are a lot of dynamic, mathematical descriptions that can explain much of it (not all surprisingly enough), but it's not necessary to understand or explain them all this format (way too long and complicated). In a nut shell, mechanical couples are formed when wind pressure in the sail(s) is resisted by the hull shape and weight. These levers are used to advantage on every sailboat, by transmitting the leverage into a sideways skidding motion (depending on wind angle to the boat's centerline). The sideways skid is limited and redirected with the use of appendages (and hull shape), typically a centrally located one (to pivot on in maneuvers) and a steering one placed aft. These aren't the best locations for them, nor the only possible spots they'll work, but over time and many different configurations, they've worked out pretty well.

A boat that is said to be "stiff" is just a personal opinion about how the boat feels, compared to others of its general size and configuration. One persons stiff, may be a little tender to another, particularly if they are sensitive to heeling or more accustomed to catamarans (for example).

It is a complicated set of variables, but it centers around how you get stability in the design. You can only get it two ways, through weight and through shape (hull form) and the vast majority of boats use both, though not necessarily equally. A catamaran gets the vast bulk of its stability from the widely spaced hulls. This shape, some well over half their length in beam, is very stiff (high initial stability), but the trade off is the point of maximum positive stability is also very low. This means it will sail flat and require a lot of wind pressure in the sails to heel it to say an average of 7 degrees, but past this point and the reserve stability, drops like a stone and she capsizes quickly. The percentage of ballast (weight) to form is very low in a stiff hull.

A mono hull that is stiff, can be so for several reasons, but in small craft, wide and shallow usually equals stiff. It too will have a steep stability curve, with high initial resistance to heel, but most small mono hulls have a higher percentage of weight and form to develop stability. This causes them to heel more, but the reserve stability is higher, meaning they'll carry sail and self right at much higher angles of heel. Most of these types of boats are still able to capsize.

Some boats are designed to have a shape that "gives" more to wind pressure, which causes them to heel quickly, then firm up. Narrow designs are typically like this and require some weight down low to keep them from flopping over on their sides. Many of these designs are stabile well past a 90 degree knock down and some, virtually uncapsizable (they'll eventually self right if knocked down). In the gallery here, my Lass design has a positive righting stability of 137 degrees, meaning she can be inverted to 137 degrees and still pop back upright. Most small, open boats have a positive stability to about 50 degrees, where they flood and flounder. If decked over, they'll carry the maximum righting force through about 90 degrees, with negative stability coming in over 120 degrees.

Since boats are nothing more then interesting combinations of compulsorily compromises, designers have to balance desires and traits against dynamic and physical reality.

Out of the box thinking and challenging the standards are qualities that are very necessary, if yacht design is to progress. Most of the revolutions in yacht design met with considerable resistance by the established (entrenched) designers or builders of their era. The first fin keel boat, the first wire rope stays, the first to put winch grinders below decks to save windage on a racer, the first to chop off the stern of a perfectly good racer to save weight (how do you think we got reversed transoms? They used a chain saw, literally) 'cause they got beat in a race and hundreds of radical or not so radical ideas, have been met with turned backs for funding or thumbed noses from the prospective buyers. Yet we still have to do it, look outside the box, that is.

Wes, A Bermudan traditional ketch is about 30% foretriangle, 40% mainsail and 30% mizzen. Some designers have played with this, but this is about how they average out in the best ones. It makes a lot of sense (aerodynamically) to get the mizzen as big as practical and as aft as possible, but in small craft this isn't always available. In a cat ketch the mizzen should be nearly the same size, if not the same. The mizzen helps the main, much like a jib does, so it serves no useful purpose to make it unnecessarily small.

You can put that rig on one of Ruel's sharpies, just put the new sail plan's CE over the old one. Actually if he used much lead (over 12%) then you can consider reducing this to around 7 - 10% (I start at 7 and go up if things don't balance). So, calculate the amount of lead he used, then balance your new sail plan over the amount you want. Sharpies carried the rig and sailed very well under it. I have many memories of them, as a young lad growing up on the Chesapeake. Do yourself a favor and devise a different reefing method then the vertical brails, they suck and make a lousy thing to have on the sticks in building winds. Even the old working sharpies discontinued their use around the turn of the century (1900).

The cat ketch can reef down evenly if the sails are similarly sized. The working sail area on that boat is 152. Personally, I keep the working area under 170 or you'll be reefing earlier then you may want to. You can always boost light air performance with a mizzen mule or possibly a headsail.

An additional mast step for reefing is a common ploy in small craft and several versions of the sharpie included this feature. If this will be a heavy air step, I'd to move this sail's CE further forward (maybe 2%) then the percentage used on the working sail plan, so you can counter any weather helm, brought on by stiff winds. At first glance, the drawn sail plan here looks to be slightly forward of where it may like to live. I haven't measured anything, just how it "feels" to me. Your version looks more "sharpie" to me, then a single stick version.

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I've read this entire thread now and from what I've read, and having built a Princess, a CS 17 and currently working on a CS 20, I'd venture that the Princess 22 has 90% (or more) of what you outlined as what you want. The only thing it DOESN'T have is the pop top and the cockpit is so large, with the full seated headroom below, I think you wouldn't really miss it.

By the way, the Princess sails quite upright and quite solidly. Hard on the wind sailing with one in our Meridian 25 sloop, we edged away, but we were rail in the water and he was heeled at MAYBE 15 degrees. This in winds where he had just shaken out reefs. When we cracked off, he pulled away from us. The Meridian has 2300 pounds of cast iron on her keel, a 7 foot beam and a wineglass hull.

Of course MY wife was at the helm cause heeling just makes her go "Yeehahhh" :lol: She LOVES to drive the boat HARD, just like she used to LOVE riding the wire on our catamarans we used to sail.

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Thanks PAR... if my calculations are correct (admittedly, that's a big "if"), my sailplan actually places the CE about 3.5 inches aft of where Parker's single sail would locate it, and yet (as you mentioned) it still looks slightly forward to my eye also.

Assuming Parker has the CE placed accurately (I presume he has it balanced over the CB correctly), it is very difficult to make the mizzen any larger without also making the foresail significantly larger (to preserve the balance of the CE), but then it looks like I would run into problems with overcanvassing. As you can tell in the pic, I had to place the mizzenmast alongside the CB trunk to get it forward enough to balance. Also, this boat is only 6' wide at the sheer (less than that at the waterline), so I'll be she would sail very easily even with less sail than this.

Parker told me that at least one person has built this boat (the picture on Parker Marine Enterprises website) and reported that she sails "extremely well" with the single sail. So I assume the CE is calculated correctly (I suspect Parker would have mentioned it if modifications had to be made).

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i know of one Parker 27' sharpie that shows up at boat shows regularly. Wins a lot of trophies because it is beautifully built. He does not sail it much though and reports that it is pretty tender and probably over canvased. Stepping the mast is an issue also. He built a tripod rig to raise it but I have seen that fall down with the mast . Pretty boat but probably not an easy daysailer.

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Hi Tom,

I suspected it wouldn't be an easy daysailer (especially stepping that 26' mast), which is why I started toying with shorter masts and a split rig. I could even scale them a bit smaller, but this is a difficult boat to balance since the CB seems well forward for the overall length.

Did that fellow you mentioned trailer his sharpie? If so, do you happen to know if he thought she was a pain to trailer? 27' is so long I'm still not sure I would want to build a boat that large for trailering, but I can't get those lovely lines out of my head, so I keep coming back to her.

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Ray, sorry that I mis-interpreted the intent of your Gordy comment; I understand what you are getting at now. Still, pretty is nice to have, but, like you say, you can't see it when your on it.

Par, thanks for your further explanation of your intent behind your previous healing comments. I have to admit that I was a little piqued as it appeared to me as a bit of a put down on my looking for a stiff boat. As I alluded to, the intent of this boat is for social sailing, so stability is an issue. What better way to get together with family and friends! For other types of sailing I have my canoe, my dinghy and family access to a Zuma and a 420. Next month I will be taking a ASA 103 Basic Cruising course and then have access to a rental Catalina 28 and 30. I believe that my wife will gradually get used to some healing, but it will take time. Last October we went out on a Beneteau 362 as guests and we did some hard heeling as we approached the Throgs Neck Bridge and my wife had white knuckles. But, to her credit, she is still willing to go out.

Thanks for the very detailed comments on boat design. I know that this is a complex subject and that there is constant innovation (lord knows, I'm always playing around with different, sometimes subtle rigging changes with my small boat). Wait till I get to that point with the Caravelle 14 I'm building. Actually, I am already considering a change in what the plans call for. The sloop rig is supposed to have a 21' mast and 7' boom. I think theist the mast is way too long for trailering, so I want to go with the shorter mast of a gunter rig. I really haven't found anything that tells me what the optimum size ratio is between the mast and the yard (i.e 2/3 mast - 1/3 yard - how much overlap).

Charlie, you may be right about the Princess 22 (and my gut tells me that as well). Just want to keep looking so that if I go in that direction I know that this was undoubtedly the best choice. Now if I can only figure out how to get it to clear 6'10" on a trailer ....

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Wes, I have a fair amount of experience with sharpies and many sets of plans for them, including a few of my own. Most of the "older" ones are complete sets and long been in the public domain. Chapelle, Monk, Geary and others penned these when many still worked for a living. File planked bottoms, round and square sterned, plywood adaptations, a bunch of them, most for reference material, all but a few have the cat ketch rig, which they are well suited.

A 27' traditional sharpie is a hefty craft and quite a handful to muscle around at the loading ramp. Early plywood versions tended to also be heavy, especially the bottom (a 27'er may have had a 1" thick ply bottom) because much of it's stability can be gained there. Later renditions have lightened up this antique sailor, making them a good bit better to trailer and launch. The latest "re-creations" of this boat type, have increased the beam/length ratio, though still narrow, making them less tender as the scalded dogs our grandfathers sailed. Having sailed both types, the young man in me prefers the 6:1 B/L on the bottom ratio many of this type carried, but the arthritis in my joints forces me to look more fondly toward the wider, increased flare, modern versions (like Mr. Parker's). If you'd drop me an email I can show you where to find some of these old designs or can send you copies of mine.

George, the gunter rig isn't one of my favorites, having had less then pleasant experience with jammed slides and awful twist issues. How about a highly peaked gaffer. Maybe a two piece stick?

I often take out my former pastor on daysails. He loves to sail, but gets nervous with high heel angles. He use to enjoy it much more and heel wasn't an issue, but at 78 he's lost confidence in his ability to move around and grip things as he once did. I'm constantly dumping pressure and letting the "tops blow off" so he can have his day in the boat, so I surely understand your concerns. He gets pissed with himself, because he wishes he was a hundred pounds lighter and 20 years younger, but that's not how it is. I enjoy the extra ballast and have told him so, much to his dismay (we're good friends, but he's 270 pounds and 6' 7"). We tell stories of the "good old days" when we were younger, just barely past the immortal stage of life, enjoying a few hours on one of our local puddles. Mostly we're grateful to be out of the other half's hair.

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