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Modern design + full keel?

10K views 45 replies 19 participants last post by  Classic30 
#1 ·
Hi guys,

I've been following the forum here for a while and have read a lot about the difference between full keel vs fin keel and its related (interesting) debates.
I have also been looking around for different designs of boats like bavaria, jeanneau, beteneau, hunter, etc, most of which have fin keels while most of the full-keeled boats are the heavier, older design type of boats.

This left me wondering, are there much modern design boats with full keel out there?

Thanks in advance.
 
#2 ·
There is no such thing as a modern design with a full keel. The two terms ('modern' and 'full keel') are mutually exclusive. That said there are some companies which still build full, or nearly full keel boats. They tend to be very expensive if built properly, and not worth messing with if they are not.

Jeff
 
#3 ·
Island Packets are the only ones I know that are full keel in production. I know Bob Johnson has change the design of the keel a few times over the years. Having said that I am not sure if he is building many boats these days.
 
#12 · (Edited)
And if we are going to be technical about it, an Island Packet is a very long fin keel with a post hung, spade rudder. And I am not sure that I would call that a modern boat. Jus' say'n

zeuss said:
Thanks for the comments.

I'm sorry I didn't make myself very clear perhaps, or at least could have been more specific. I actually mean the hull shape as opposed to the interior.

Most of the full keel boats I see on the internet look to me like those very old fisherman boats one sees so now and then.

I'm trying to find out if there is anything that resembles what we see in a modern sailboat of the manufacturers I mentioned above. For me that would mean a smaller cockpit area, a flatter hull, not so many big windows, etc.

Anyways, something that looks more like a bavaria 42 than a tayana 37.

I understand that perhaps I what I'm after is just impossible or unthinkable in boat design, if that is the case then I just want to know that and ideally why if someone can help.
But for the most part, I don't know of any boats that have a modern hull form and rig but with a full keel. There are quite a few boats with traditional looking hulls but with modern keels and rigs.

In reality, boat designs operate as a system. Modern hull forms have comparatively little drag and so would not work well with a high drag keel or rig. You would end up with a pretty foul craft with all the liabilities of both schools of thought but that did nothing very well.
 
#4 ·
Then again, one must define "Full" when it comes to full keels.

Mine is a shoal draft draft keel that is simply wider than it is deep :)

It's not full in that it does not extend to the rudder (I'd call it a 2/3 keel, but I'm no boat expert).
 
#5 ·
There's still a decent variety of newly constructed full keel boats out there for purchase, but as Jeff points out, calling them "modern designs" will likely spark debate.

In any case, these are full keelers still in production (but most are older designs):

Cape George cutters
Falmouth Cutters
Bristol Channel Cutters
Island Packets
Hans Christians (cutaway full keels)
Robinhood 36/40 (Cape Dory/Alberg designs)
Fisher Yachts (motorsailers)
Tayana 37
 
#6 ·
Dana 24 should be on that list too.

Perhaps the buyer is looking for a modern interior, not a modern hull shape. The Dana 24 could arguably fit that description as well, since it doesn't have forward bulkheads and isn't full of ugly 70s/80s plaid.
 
#7 · (Edited)
Thanks for the comments.

I'm sorry I didn't make myself very clear perhaps, or at least could have been more specific. I actually mean the hull shape as opposed to the interior.

Most of the full keel boats I see on the internet look to me like those very old fisherman boats one sees so now and then.

I'm trying to find out if there is anything that resembles what we see in a modern sailboat of the manufacturers I mentioned above. For me that would mean a smaller cockpit area, a flatter hull, not so many big windows, etc.

Anyways, something that looks more like a bavaria 42 than a tayana 37.

I understand that perhaps I what I'm after is just impossible or unthinkable in boat design, if that is the case then I just want to know that and ideally why if someone can help.

Hope this makes it more clear.
 
#11 ·
Thanks for the comments.

I'm sorry I didn't make myself very clear perhaps, or at least could have been more specific. I actually mean the hull shape as opposed to the interior.

Most of the full keel boats I see on the internet look to me like those very old fisherman boats one sees so now and then.

I'm trying to find out if there is anything that resembles what we see in a modern sailboat of the manufacturers I mentioned above. For me that would mean a smaller cockpit area, a flatter hull, not so many big windows, etc.

Anyways, something that looks more like a bavaria 42 than a tayana 37.

I understand that perhaps I what I'm after is just impossible or unthinkable in boat design, if that is the case then I just want to know that and ideally why if someone can help.

Hope this makes it more clear.
I guess not, I mean clear, at least not for me:

You want a kind of a Bavaria 42 with a full keel or a more traditional design, narrower, with a small cockpit and a fin Keel?

As it was already said in what regards modern boats (recent designs) with a full keel, with the exception of the Island Packet (I don't know if we can consider that modern even if the design is recent) I don't know of any. A British firm presented some years ago a design of a steel boat with a full keel but I believe they never made one and went bankrupt.

More traditional, I would say classic looking boats with a small cockpit, with a fin keel there are several, most of them are just week end cruisers but some are cruising boats, beside being beautiful to look at.

Regards

Paulo
 
#8 · (Edited)
Interesting question.... a wide flat hull (like offshore 40-class) with a plumb-stem faired into a cut-a-way forefoot and a long but shallow and narrow keel similar to say ...some of the old Viking longships ?...IMHO there would be of course a sharp increase in tracking ability at the expense of some speed with that extra surface area/drag, but the right design certainly might retain a respectable degree of the high-speed "skimmer" qualities of a 40-class type design. However, lacking the deep ballast "bullet keel" it would offer less far stability in heavy air even if the shallow keel was ballasted with expensive lead...It it would be quite practical in terms of access into shallows and far less susceptible to keel damage...I doubt it would improve some of the pounding tendencies of the wide flat modern boats...

Interesting concept Zeuss...You could conceivably have an auxiliary deep "emergency" swing keel " or even canting swing keel I suppose that could be deployed in heavy air...but the rest of the time stay in "up" position in it's nice hydro-dynamic C/B trunk or or slot as integral section of the overall "full keel" concept...a hybrid from the hybrids...but for the cruising public or the beercan racer/cruiser crowd
 
#13 ·
I think one of the things that makes a "full keel" work is that they tend to be narrower. Seems to me you are talking about having opposing design goals. Noting is really gained by the full keel, but a lot of performance is lost so why would you want to do that? Especially if you are talking about putting it on a wide flat modern hull shape. You would just be putting more whetted surface area, yet getting less righting moment, and stability. But I am no naval architect. The nature of a full keel is slow and heavy. Once you add any width you are going to slow it down even more.
 
#14 · (Edited)
My initial thought was that with a full-keel a modern boat could benefit by becoming more stable (hence safer) in blue waters. At this point I didn't know that the impact of the hull design would have that much of an impact on the overall performance of the boat. This relationship is what I was curious about. I now have a better idea as to why. Thanks guys.

I personally like the design of modern boats, but the thought of going to sea (coastal initially) with boats that have been labeled as "unstable" by many as soon as the wind picks up is not really reassuring.
I know this may be an exaggeration from my side, that there are loads of boats with fin keel which are indeed very stable indeed, perhaps I'm being too conservative here? I'm all for safety at sea no matter what.
As I said above, I'm fond of these new boat designs, but I wouldn't go as far as to trade safety for beauty, unless I can do something to get similar performance (stability, safety, etc).

I don't care so much about speed as long as the boat is not one which would force me a fast escape from mid winds. :)
 
#16 ·
My initial thought was that with a full-keel a modern boat could benefit by becoming more stable (hence safer) in blue waters. At this point I didn't know that the impact of the hull design would have that much of an impact on the overall performance of the boat. This relationship is what I was curious about. I now have a better idea as to why. Thanks guys.

I personally like the design of modern boats, but the thought of going to sea (coastal initially) with boats that have been labeled as "unstable" by many as soon as the wind picks up is not really reassuring.
I know this may be an exaggeration from my side, that there are loads of boats with fin keel which are indeed very stable indeed, perhaps I'm being too conservative here? I'm all for safety at sea no matter what.
As I said above, I'm fond of these new boat designs, but I wouldn't go as far as to trade safety for beauty, unless I can do something to get similar performance (stability, safety, etc).

I don't care so much about speed as long as the boat is not one which would force me a fast escape from mid winds. :)
I respectfully suggest that you are misunderstanding something about fin keels versus full keels. There is absolutely nothing inherently 'unstable' about a fin keel, or inherently more stable about a full keel.

From a design standpoint, a sailboat's need for stability is a relative thing, by which I mean, that stability should be thought of relative to the boat's drag. The more drag a boat has, the more sail area it needs to move, and the more stability that a boat needs to carry that sail area. What ends up happening with high drag vessels (full keel boats that are also short for their weight) is that they tend lack the stability to carry as much sail area as they would ideally have. Work-arounds like a low aspect rig, allow greater sail area, but in doing so end up with lower efficiency sail plans, so much more sail area is required for something approaching but not achieving the same performance.

This combination of high drag hull, lower efficiency rig, and lower stability relative to drag usually results in some mix of decreased performance, more frequent sail changes, greater heel angles for a given relative performance, bigger and harder to handle sails, and/or more motoring time.

Because of that, in a broad general sense, it is much easier to achieve a higher useable stability in a fin keel design than it is in a full keel design. That is why modern boats tend to employ more efficient hull fiorms, keels, rudders and rigs. There may be a case why someone would prefer a full keel, but if it is about greater stability, then it is not because the boat has a full keel, but because of other factors that go way beyond the length of the keel.

Jeff
 
#15 ·
Zeuss,
Not clear on what you are calling 'stable' - the only advantage regarding stability that comes to my amateur mind is that a full keel is likely to track on course better than a fin keel.
I really don't mean to start an argument with that statement, I have no proof other than what I've read.

Capsize wise regarding stability the rule of thumb is more weight further down is better.
The calculated AVS for my Irwin 38 CC with a design displacement of 20k, and a realistic cruising weight of 24k pounds is in the 130 degree range, either way if I fully turtle I ain't see daylight on the deck again.
That's the same for most boats by the way.

Keep in mind that most folks who are cruising on a full keel boat are not exactly white knuckle thrill seeking adventure junkies - so we are inherently conservative, on a conservative boat. That makes them more stable :)
 
#18 ·
I might be sticking my neck out but when you said smaller cockpits it made me wonder... Modern boats have huge cockpits but also have a scoop transom so taking green water isn't an issue. The reason I bring this up is tat it appears you are reading far too much and not sailing enough. I would suggest getting out and sailing both designs as often as possible it could save you thousands in the end. An aside, if your boat is being pooped you are doing something very wrong, in the real world this is a very small concern to a skilled sailor. One of the big problems with forums and the internet is that rather than get out and learn what we like we read way too much about it and start to form opinions about things we know nothing about. This is meant to be positive btw :)
 
#20 · (Edited)
not sure I fully understand the question, however I think I'll chime in on this. I should think that a "modern" Tartan T-27 would be a sweet boat. With just a bit more beam and longer waterline length she would be a great little river/lake boat what with her shallow draft. If it were possible to keep her lovely lines intact all the better~~james smith
 
#23 ·
Most yachts really shine on a beam reach in 15kts+.... just saying.
Very true, now if one can also shine reasonably well on an upwind, along with downwind, then one has what most of us would call a reasonably well rounded boat! If it only reaches, or goes up wind, or down wind well, then you have a boat built for, not a generally speaking well rounded/sailing boat. That is what I would like to think, most of us strive for! At least I do!

A fat assed boat with a full keel will not do well in light winds, heck, a fin keel boat with a fat ass is not always good in light winds! now add the extra drag from a full keel! no thank you!

I also am not sure I would call an IP a true full keel boat, probably more of a cross breed. I do not see anything special about them personally, and that Jacket design is not that great either! A lot of money for nothing too exciting! A Catalina would be a better all around boat IMHO!

Marty
 
#25 · (Edited)
Well you know Cam,

Being as we are BOTH "BETTER LOOKING" than the fugly moderator with a wing keel catalina, we BOTH know a deep fin will be better than a shallow or wing.........assuming one has enough water depth below us, then when it is shallower than you draw.......well then we introduce you to Mr Wilson, when I find the story of mr wilson, I will post it, quite funny actually!

marty

look up "what is a wilson" fifth letter to the editor!LOLOL
 
#27 ·
Irwin's and IP's shared in that the IP designer (Bob Johnson) cut his teeth so to speak on Ted Irwin's floor building Irwin's.

I don't have extensive experience on my Irwin yet, but regularly sailed in company with a IP 34 of mid 80's vintage skippered by a very experienced owner when I had my Gemini.

She did well enough in the pointing to arrive at the designated anchor and looked a lot more comfortable for the crew than either me (on the Gemini) or CraigToo on his Sabre 34. I'll admit C2's Sabre got there well before the rest of us due to an extra 5 or more degrees of point (and less leeway than my Gem made). That just gave him time to put all the flying objects away below decks, something neither I or the IP had to do.

On the other hand when I sea trailed my Irwin she did a steady 5 knots in 7-10kts of wind at a estimated apparent 45 degrees. Nothing wrong with that in my cruisers opinion. Tacked right around too, no problem.
 
#30 ·
I don't have extensive experience on my Irwin yet, but regularly sailed in company with a IP 34 of mid 80's vintage skippered by a very experienced owner when I had my Gemini.

She did well enough in the pointing to arrive at the designated anchor and looked a lot more comfortable for the crew than either me (on the Gemini) or CraigToo on his Sabre 34. I'll admit C2's Sabre got there well before the rest of us due to an extra 5 or more degrees of point (and less leeway than my Gem made). That just gave him time to put all the flying objects away below decks, something neither I or the IP had to do.
My first Caribbean charter was on a CYC Sabre 362. My wife and I got beat up (including a serious fall from the companionway) sailing from JVD to Trellis Bay in a boat that couldn't sail to weather to save itself. It didn't help that the main had no roach and no battens (even my 9' Dyer Dhow has battens!). The sails were blown out and we couldn't point any better than the Island Packets we chartered years later. That was an eye-opener. Our subsequent charters included Beneteau, Waquiez, and Jenneau, before we migrated to Island Packets out of St. Thomas.

Now, we enjoy performance, but when we are on a charter, we aren't there to race and don't want any handling surprises, particularly when the wind pipes up. The IPs have their handling issues and require some muscle to steer but they are fairly solid. If we have to go to weather for any distance, like from St. John to Virgin Gorda or Culebra to St. John, we will use the "iron genny". It's nice to arrive in a more relaxed state--which is the point of our Caribbean break.

Bottom line: Give me an IP on a charter, but I'll stick to my own Clearwater 35 in home waters for a more exhilarating sail.
 
#32 ·
Drop keels have a place also. I believe J-boats builds a version, as do Jeanneau, Beneteau in the smaller sizes, ie under 35' or so. Hake is another builder of ALL CB style boats. Ovni?!?! is also a builder, as are numerous other European builders. Generally speaking, there are not too many north american modern design builders.

marty
 
#36 ·
I think one big problem is that people look at boat design as a bunch of unrelated elements. Traditional sails only get used on older hull designs. Full keels are only used on older hull designs. Then they try to compare these elements as if all things are equal. But that really is like comparing apples to oranges. No matter how good a sprit sail may be on all points of sail, if the boat it's on has a less efficient hull design, it's not fair to compare it to a Bermuda on a racing hull. Similarly, full keels only get put on displacement boats, often with a broad, full bow, as a rule. My boat has very little draft, outside of the DB or the, new, full keel. It is slender. It has a very narrow entry and, then, after the middle where the beam is greatest, it tapers, a bit, to the transom. It is a planing hull, with the hull, aft, being nearly flat. When I sail to wind, I move me weight, even with the middle of the boat, where the DB used to be. This raises the transom out of the water, reducing wetted surface, in the rear, and brings the narrow bow deeper in water. If you really look at the shape the hull is presenting, to wind, the hull is helping the keel to avoid leeward motion. In fact, if I pinch her, I can sail a little closer than 45 degrees to the wind, especially in a good breeze. I have always kept my weight to windward, when tacking, until the bow has passed the eye of the wind and is actually on the new tack, because she is light and doesn't shoot as well as a heavier boat. I still do this when tacking. It works well with the full keel.
 
#37 ·
One thing I forgot to mention, and should point out, is that my rudder is hung off of the transom, as is normal in a dinghy, and the keel stops at the waterline, when the boat is sitting on the water without weight leaned towards the stern. This means that, although the keel travels nearly half of the water length, there is a foot between the end of the keel and the beginning of the rudder. This may have some effect on how the keel functions. It may give it some of the properties of a shallow fin keel, since, most often, full keel boats have the rudder mounted on the keel.
 
#43 ·
I got interrupted by having to go work. LOL> What I am saying is, a long keel is not the only type of full keel. It's one design. And, really, the long keel on a modern cruising sailboat is a lot different than the long keel on the Swallow, from that book about swallows and amazons.

The cruising sailboat usually will have a displacement hull with a good bit of non-keel hull below the water line. It's keel will be deeper and fuller than on the 1800's style sailing dinghy. The keel will also tend to be a triangular affair, wider at the hull than the bottom of the keel. The dinghy, by contrast, will tend to be beamy with a full entry and a moderate amount of draft. It's keel will be shallower and not have much taper in cross section; having nearly vertical sides. The keel will tend to get wider towards the stern. The rudder attached to the keel.

Go back in time further, to the Germannic boats of the Viking age. There, you have a hull which is close a modern racing hull. It has a narrow entry ( and stern, as well ) and a fuller mid section.
It carries very little draft. The keel, shallow like the Swallow, will be deeper in the middle of the boat, than at the ends. The rudder is a steering oar, off on the starboard side, which is how starboard got it's name.

This full keel looks nothing like the cruising sailboat and the hull is very different than either of the afore mentioned vessels. The Viking ship is a great example of exactly what I am getting at, in my previous post.

While we have hulls left, in various conditions, no Viking sails have been found. In the late 1800's, in Scandinavia ( Denmark, I believe )i a replica of a longship was built to sail to America as a poke in the eye to Columbus, on Columbus day. Time was getting short and the builder/captain cut corners by taking the tall, square sail, off of a tall ship he owned, and fitting it to the longship. He sailed it to America. Now, since then, all ( but one ) longship replicas have used a tall, square sail, even though there is no evidence for this.

Even with such an inefficient sail ( although the beitass used by the Vikings really helps out a square sail, when sailing to weather ), these replicas have such an efficient hull design that they can sail upwind. I believe it's something like 50 to 55 degrees from the wind, which is better than the tall ship the original sail came from.

However, Viking age artwork shows a different type of sail. It shows a low, rectangular sail, wider than it is high ( a 3 to 1 ratio ). One replica, the Sigrid Storrada, was built to this spec. Interestingly, that sail answered a few questions about the Gokstad ship, which had gone unanswered with the allk, square sails. Despite being supported by the Viking's own art and despite the lack of evidence supporting the tall, square type of sail, this sail choice is still very controversial. Go figure.

Anyhow, the same hull, built like the Gokstad ship, with this "new" sail, is reported to sail 45 degrees to weather at around 5 knots, in 'average' winds. Quite acceptable, even by modern standards.

The only difference? The better sail. The "new" sail, when tacking, dips it's yard, like a balanced lug. It's a far better sail, on the wind, than the tall, square sails.

So, what I am getting at is that people judge the individual elements, of a certain design, by the qualities of the design it is used on. That's not really fair. All of the elements of a design work together, in concert, each to give the whole a certain quality of performance. A great hull, hampered by a poor sail, will not perform as well as it should. A great sail, like a sprit sail, hampered by a poor hull, will not perform well.

For instance, sprit sails were popular during the golden age of sail. They were a working sail on working boats. Working boat hulls are designed to carry big loads or to dredge for oysters or to fish from. They aren't necessarily designed for top performance. On the other hand, great racing boats aren't good for much else. I think the story of the Bluenose and how she came into being illustrates this well.

Life is full of compromises. You can have a racecar. You can have a luxury car. You can have a truck. You can have a fuel efficient economy car. But you can't have a vehicle that is all of the above. You have to decide what your purpose is and design for that.

People tend to always put Bermuda sails on performance hulls and sprit sails on 'traditional' hulls. Then they want to say that the sprit sail is not as able as the Bermuda sail, to wind. But that's comparing apples to arranges.

Everyone says that the same boat, with a full keel, will not perform as well as it did with a skinny fin. But where is the evidence? Where is the modern racing hull with a full keel? In order to prove something, scientifically, you need controls to rule out other possibilities.

Plus, there are so many different full keel designs. Which one is most efficient in which kind of application? To get a real answer, you'd have to take a number of boats, with that modern racing hull, and try different keel designs and then compare the results.

Of course, you also have to consider rudder design.

You have a rudder hung from the end of the keel, at the very stern, on a long keel, in a modern cruiser. You have the starboard mounted rudder on a longship. You have the keel mounted rudder, mounted deep under the boat, on one of those 1920's racing boats. You have the type of keel rudder combination that has the bite out of it, to reduce wetter surface, in front of the rudder. And, you have a transom hung rudder, like my boat is now, that is a foot from the keel of the boat, because the keel ends at the waterline and the stern is an inch out of the water, when the boat sits balanced.

The rudder has a big effect on how the underwater 'foil' performs.

So many possible combinations of elements, yet so few have been tried. You really judge any one design element until you have seen it perform with, at least, the majority of possible combinations...or at the very least, you can't compare the abilities of a full keel, on a 'traditional' hull to the abilities of a skinny fin on a performance hull. It would be like putting an airboat and a cigar boat on the water, in a swamp, and using that to judge which is the better boat.

Myself, I was willing to experiment...and I have been rewarded for it.
 
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