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Discussion Starter · #1 ·
Good morning everyone:

Compared to a shoal keeled sailboat, is the greater ability of a fin keeled or long/deep keeled sailboat to "claw" off a lee shore due to its higher pointing angle relative to wind direction, the improved hydrodynamic lift element of the keel design, the superior maneuverability or a combination of any or all three?

Many thanks for all well intentioned answers.
 

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all three... ;)
although the higher pointing ability is more or less due to the improved hydrodynamic lift... so it could be seen as only one point and the resulting effect...
although the better lift also results in less drift to windward on the course steered...
the better maneuverability lets you tack faster which results in less windward drift during the maneuver...
 

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Mermaid Hunter
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It all depends.

First, I think that the skills of the skipper and crew are generally more important than the capabilities of the boat.

Second, the "claw off a lee shore" mantra is over done. If you can make progress to windward and can tack as needed you will eventually be okay. That isn't to say that pointing higher isn't good, but course made good is ultimately more important.

On to the boat:

It depends. On my boat, the difference between polars of the regular and shoal keels is less than a pencil width. Other boats will see more leeway or poorer pointing (or less or better respectively) between the keel options. You have to be specific and look at the data. There is no one size fits all answer.

In general, a fin keeled boat--shoal draft with a bulb, wing, or Scheel keel or not--will point higher with less leeway than a long keel (full or modified full) boat.

Rudder design and execution have a similar effect on lift and the ability to point, but again the ability of the crew to sail the boat to keep the rudder and keel generating lift is primary.

I'm not clear on the maneuverability part of your question. Certainly the rotational inertia of a full keel is greater than a fin keel but unless you are tacking up a channel it isn't clear to me what difference that makes. In fact in some cases the greater inertia of a full keel will help maintain heading (not necessarily course) in a sea. How much you care depends on whether you are hand steering or using an autopilot, and in the latter case the data inputs and the algorithms in the a/p that act on those inputs.

Where do you plan to sail? What boats are you considering?
 

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are you sailing flying cloud or something?

I cant understand the whole you need to buy a fin keeler to move off a lee shore...its making headway thats important...

and knowing how to sail

I too agree its greatly overdone, to the point that its part of the reasons people have 50hp diesel in a damn 30 footer...

if you dont learh to sail well on all alngles then practically any shore is a lee shore, regardless of wind and wave patterns...

learn that and you wont find yourself in a scenario reminiscent of james cook fighting a lee shore in australia or something
 
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Discussion Starter · #5 ·
Thank you for the input. So in effect the lifting effect of the keel pulls the boat in the opposite direction(more or less) that the wind is trying to blow the boat. It would seem that no matter the keel, given adequate room to make way and maneuver, any sailboat sailed properly, unless the winds are totally overpowering will be able to "claw" off a lee shore. It is really a matter of how fast or slow and how easy or difficult. It seems from my research that one limitation of a shoal draft sailboat is how much sail can be carried for any given wind speed. At any angle of heel a shoal draft boat will have less of her keel still in the water compared to a deeper keeled boat. This would indicate to me that significant reduction of sail area would be necessary to maintain directional control. Am I thinking correctly?
Regards
 

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I wont dabble in this too much(cause others will get very technical and start talking major design parameters and whatnot) but...

I will just say this

a very shoal draft boat is at a disadvantage, this is mostly true of some centerboarders when the board is up or jammed or whatever

its entirely possible to be blown sideways to leeward if the wind is too powerfull in this case yes...you are absolutely in a clawing off a lee shore scenario

im not a fan of centerboarders...some I wouldnt dare sail on..practically there is no stub or false keel...going down the center of the boat, so if you have no centerboard or its jammed you cant sail at all

maybe downwind ever so slightly...but you will lose controll every other puff of wind...

a full keeler just loses a bit of pointing angle, but once going actually tracks straighter and yaws less

a deep full keel or 3/4 cuataway has advantages as well...

fin keelers are known for being squirelly not all but its a known traight, there is less surface area and you have 2 yawing points...

usually it will take more effort on the skippers behalf to sail a squirelly fin keeler than a full keeler

in any case...


go sailing on a dinghy...put fin down then try to sail with daggerboard up...this will give you a very clear picture on what a lee shore can become...

basically you will learn that you need to have movement through water on almost every boat regardless of keel shape in order to make headway

you will also see at what depth basically the fin or keel starts to work well...you ca get withinh an inch of useless and or sailable...

if you cant you are in varying degrees of "being stalled"

one of the first things you have to teach kids in sailing school is the importance of daggerboard position...

if you cant put it down you arent sailing...and you wont be able to get offshore...there were always a couple or 3 boats that could never push out enough to get into deep water in order to put board down then fall off to one side and pull in tight in order to "claw off"

anyways
 

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On the more traditional boat, which is most likely a great deal heavier, I would think that the weight is an advantage, if the seas are up. Being able to maintain forward momentum when slamming into seas must compensate for the pointing ability of the lighter, more agile vessel. I rarely see the more modern sub 50 footers pointing significantly higher or going significantly faster when crossing the channels between islands down this way, if the seas are up.
So if one is "clawing off a lee shore", chances are it won't be in calm, pleasant conditions, perhaps the better performance boat won't actually be doing any better.
 

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I reed all these posts. Always searching for more information and another perspective.
Christian sums all that this non sailing wannabe has learned.
 

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On the more traditional boat, which is most likely a great deal heavier, I would think that the weight is an advantage, if the seas are up.
Nothing is simple. Sail plan, the ability of the crew to sail the boat, hull form, course, sea state, ... all are factors.

A Passport 40, for example, pretty well stops in a high sea. It's too heavy to accelerate decently so you move pretty slowly. You may well be comfortable but your passage will be long.

A Hylas 46 on the other hand doesn't get stopped as much in a seaway and accelerates better when it does slow down.

Granted these aren't apples to apples to comparisons, but find a couple of boats that can really be compared apples to apples. *grin* Weight helps but hull form is more important. Sail trim is even more important. Sail fast.
 

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Nothing is simple. Sail plan, the ability of the crew to sail the boat, hull form, course, sea state, ... all are factors.

A Passport 40, for example, pretty well stops in a high sea. It's too heavy to accelerate decently so you move pretty slowly. You may well be comfortable but your passage will be long.

A Hylas 46 on the other hand doesn't get stopped as much in a seaway and accelerates better when it does slow down.

Granted these aren't apples to apples to comparisons, but find a couple of boats that can really be compared apples to apples. *grin* Weight helps but hull form is more important. Sail trim is even more important. Sail fast.
I don't think it important to bring the crew into these boat to boat discussions. It could be the same crew sailing both boats (at different times of course).
But if you want to put my old Pearson against a more modern, much lighter let's say Bene 50, with nearly comparable sail areas, then I believe the heavier boat will pull off a lee shore more quickly and easily in a big sea. I would love to find a Bene 50 to sail with as we head for Grenada, to put this to the test, so if you know anyone headed south from Dominica in the next few days...
I do know that with a just Yankee jib and deeply reefed main, we seem to do much better in the channels than the smaller (38 to 45') Benes, Bavarias and Jeanneaus with genoas and more main, ie; more sail area for the size of the boat. From my observations, it seems counter productive to push those lighter boats closer to the wind and driving more deeply into the seas. Therefore, I see little advantage in high performance cruising boats, at least in the eastern Caribbean. They are certainly not more comfortable on the channel crossings, nor at anchor, and really, for most liveaboards, isn't that by far the most important thing in a boat?
However, I'd be the first to admit I have not sailed any of these boats, so I can only give my opinions based on observation.
 

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Mermaid Hunter
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I don't think it important to bring the crew into these boat to boat discussions. It could be the same crew sailing both boats (at different times of course).
What I'm trying to make clear is that the sailor is generally more important than the boat. For most people an investment in training and practice will reap more benefits than a new sail.

But if you want to put my old Pearson against a more modern, much lighter let's say Bene 50, with nearly comparable sail areas, then I believe the heavier boat will pull off a lee shore more quickly and easily in a big sea.
I have great respect for Pearsons and have enjoyed my time on them. Good solid boats with respectable performance.

I've also sailed Beneteau 50s offshore. They aren't all that light and their performance in a sea is pretty good.

I think part of the real world performance issues is that people sail their boats over canvassed with sails intended for light air and calm seas. They are heavy enough to carry the sail, but the heel induces weather helm and the rudder angle slows down the boat as does asymmetric hull form drag. We won't even talk about sail trim. *grin*

Now if you'll bear with my warped sense of humor, I'd be happy to borrow a Bene 50 and sail against you off a lee shore if we can then swap boats and do it again. I get Jon Eisberg, Sarah Southworth, and Chip Estabrooks as crew. *grin*
 

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its the skipper thats most important

being overcanvassed is the best way to be blown onto a lee shore sideways...flat is fast is KEY here

think of tacking up a river here and youll get off in no time
 

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being overcanvassed is the best way to be blown onto a lee shore sideways...flat is fast is KEY here
Agreed. Similarly, sometimes course made good will be higher by not pointing as high - back to the skipper or navigator being key.
 

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Now if you'll bear with my warped sense of humor, I'd be happy to borrow a Bene 50 and sail against you off a lee shore if we can then swap boats and do it again. I get Jon Eisberg, Sarah Southworth, and Chip Estabrooks as crew. *grin*
Nikki and I would love to give it a go, but when it came time to switch boats, we'd be at a serious disadvantage. She's not sailed any other vessel and is definitely spoiled by the simplicity and ease of sailing this old gal.
But do keep in mind that I do not race this boat, ever, so it will be an "experiment" in windwarding, OK? lol
As to weather or lee helm, I've always considered an uncentered rudder to be the equivalent to dragging a barn door through the water. But it's like that old Almond Joy commercial; some days you feel like you are sailing in the groove, and some days you don't.
 

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Mermaid Hunter
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As to weather or lee helm, I've always considered an uncentered rudder to be the equivalent to dragging a barn door through the water. But it's like that old Almond Joy commercial; some days you feel like you are sailing in the groove, and some days you don't.
I mostly agree. On most boats you get some lift at small angles of attack. Five degrees seems to be the sweet spot. On my boat and similar medium weight cruisers I reef on weather helm (at ten degrees) rather than heel angle or other indicator.
 

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Over Hill Sailing Club
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Being that any sailboat should be able to beat against the wind at some angle, "clawing" off would seem more a function of how the boat is handled than any particular hull design. Some will be better than others but any boat worthy of being out there in the first place should be capable of making headway with wind in the sails. Awareness of the actual position/movement of the boat relative to wind and the lee shore is not easy. Determining the best angle of attack in a situation like that is a matter of just a few degrees and it's easy to miscalculate by a wide margin. The ability to tack smoothly and quickly is critical in a slow motion battle, when dealing with marginal wind or against current. Every hull design will have a point of no return when it is not possible to tack off because of diminishing lift as when a large left over sea or current is running and the wind dies. That's what motors are for:)
 
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The idea of sailing off a lee shore gives me nightmares, so I avoid that situation.

But you could get caught. There are places to test yourself and boat. One spot in particular is setting sail out of the Cape Cod Canal into the typical Buzzards Bay 15kt++Southerly.

That stiff head wind dead on your course along with the opposing current of the canal, loads up a near endless army of steep waves.

You've got to tack your way out and you're painfully aware of precious ground you've covered to windward, and how quickly you loose it during tacks. You're asking the most of a sailboat and the sailors.

We had just such a sail last season along with friends in another boat. A 'race' of course. With a deeply reefed main(doused mizzen) and a slightly overpowered 135%, we won. :)

At times like that, the extra 5 to 10 degrees our centerboard can slice off our leeway is precious. It's not the ultimate-windward degree for our boat that works best. It's the sweet spot, falling off a few degrees when the boat comes alive and she is on her feet.

The other boat a deep fin keeler(and slightly smaller), I think had too much main flying. We didn't point any higher, but we had more power-we could use, so we were faster. That's just what you need to get through the waves.

You know you've beaten Buzzards Bay after several tacks and a few miles when the currents effect wanes and the steep waves become longer and farther apart. Pretty soon the boats bow stays down, the tacks are long, and your speed begins to tick upward. Right about then, a stressful situation becomes, a nice sail.

 

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I just experienced the Lee shore problem in a Beneteau 34. We were trying to round the point of an island with an on shore breeze and would encounter currents that would stall the boat which pushed us closer to the lee rocks. After a couple of attempts I decided that we would have to put maybe 2 miles between us and the point in order to maintain control. We were on a time schedule (I know!) so I just turned and ran with the wind to round the other end of the island.
For those that have been there we were in the BVI sailing from The Indians around Carrot Rock with the plan to reach up the Salt Island Passage to return the boat to Road Town by noon. If the wind had been more Southeasterly we would have made it just fine, but the current was flowing into the Drake Channel and the wind veered to due east as we cleared the point.
So, in response to the OP, any decently designed boat can claw off a Lee shore if the crew can sail it, and you give it the time it takes to get clear and free of all the turbulence oft encounter in such situations. One thing is for sure, a stalled rudder really sucks and on a boat like the Bene we were on, the draft of the bulb keel was only 5ft and the rudder less. Also, the rudder was rounded in profile, which reduces its surface area resulting in an earlier stall point than I've experienced with the very robust rudder on my Pearson. Not being an engineer or anything like that, I can only speak from experience about the size and shape of the rudder's role in these situations, but I know it is an important element of the hull configuration.
John
 
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