Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 26-06-2013, 11:29   #46
Moderator
 
carstenb's Avatar

Cruisers Forum Supporter

Join Date: May 2012
Location: Copenhagen
Boat: Jeanneau Sun Fast 40.3
Posts: 4,942
Images: 1
Re: Wing Keel?

Quote:
Originally Posted by Don L View Post
You all now ther are deep draft boats that have wing keels don't you?

My last boat had a MASSIVE wing and a shoal draft. It pointed higher than my current deep draft boat. But that wing did make a great anchor!

Having had both I would take a deep draft boat over a wing shoal draft. It just gives a better ride and stands up to gusts better and if the 1.5' ever makes a difference I was in the wrong place either way.
Hey Don,

Think I'll change my handle to "The premier internet expert in the universe" that'll beat out your puny world LOL
__________________

__________________
I spent most of my money on Booze, Broads and Boats. The rest I wasted - Elmore Leonard
carstenb is offline   Reply With Quote
Old 26-06-2013, 19:00   #47
Registered User
 
Nicholson58's Avatar

Join Date: Jan 2011
Location: Live aboard
Boat: Camper & Nicholson58 Ketch - ROXY Traverse City, Michigan No.668283
Posts: 3,466
Images: 83
Re: Wing Keel?

Quote:
Originally Posted by Seaworthy Lass View Post
They don't work?

Then it must at least have given a phycological advantage to Australia II when Ben Lexcen's revolutionary designed yacht managed to snatch the cup away from the Americans after a winning streak spanning nearly 130 years

if you wish to emulate their success, buy a 72 foot wing keel vessel and never sail in seas above 3 feet. Note my post above.
__________________

__________________
Nicholson58 is offline   Reply With Quote
Old 27-06-2013, 03:02   #48
Moderator
 
Seaworthy Lass's Avatar

Cruisers Forum Supporter

Join Date: Oct 2008
Boat: Aluminium cutter rigged sloop
Posts: 12,819
Re: Wing Keel?

Quote:
Originally Posted by Nicholson58 View Post
if you wish to emulate their success, buy a 72 foot wing keel vessel and never sail in seas above 3 feet. Note my post above.
I thought the advantage of the winged keel in that series of races was that it allowed greater sail area or waterline length while still complying with the formula for the 12m rule. Nothing to do with the depth of the water they were racing in.

If the winged keel gave no advantage, then it must have been Aussie John Bertrand's superior skill over Dennis Conner .
__________________
"The cure for anything is salt water: sweat, tears or the sea." Isak Dinesen
"To me the simple act of tying a knot is an adventure in unlimited space." Clifford Ashley
Seaworthy Lass is offline   Reply With Quote
Old 27-06-2013, 03:49   #49
Registered User

Join Date: Aug 2009
Location: Port Welshpool Australia
Boat: sold swan new cat under construction / Canados 50s
Posts: 755
Images: 16
Send a message via Skype™ to beneteau-500
Re: Wing Keel?

well on my yacht i love my wing keel, sailing in the med where you sail into the wind constantly and i find i can also sail a lot closer to the wind than others can i out run a lot of other yachts around but yes she is a pig down wind
__________________
beneteau-500 is offline   Reply With Quote
Old 27-06-2013, 09:46   #50
Moderator
 
Adelie's Avatar

Join Date: Feb 2010
Location: La Ciudad de la Misión Didacus de Alcalá en Alta California, Virreinato de Nueva España
Boat: Cal 20
Posts: 4,640
Re: Wing Keel?

Quote:
Originally Posted by Seaworthy Lass View Post
I thought the advantage of the winged keel in that series of races was that it allowed greater sail area or waterline length while still complying with the formula for the 12m rule. Nothing to do with the depth of the water they were racing in.

If the winged keel gave no advantage, then it must have been Aussie John Bertrand's superior skill over Dennis Conner .
As I understand it the wing improved hydrodynamic properties slightly and increased the boat's stiffness slightly by lowering the center of gravity of the ballast without increasing draft (which would have changed the rating).

The net result was a 1/10 to 1/4 percent improvement in boat speed depending on exact conditions at any given moment. At the highest levels of racing this is an advantage worth the cost and there are no ancillary penalties.

Beyond the highest levels of racing differences in crew skill and sailing effort vastly overwhelm the effects of the wings.

Also wing keels have suffered in their implementation on production boats. The biggest problem has been using them on shoal draft models. While the lower center of gravity of a wing keel might be able to compensate for 2-4" of less draft, more typically shoal draft boats are 8-18" shallower.

Early production versions were also rather cookie cutter. Once a manufacturer had determined a shape for their wings, that was the shape that was used on all their boats scaling it up and down to suit. In reality for most craft wings need to be designed for that particular vessel, the interaction between the wings and the fin and even the hull is very complex. In the '80's and early '90's the theoretical and computational facilities just weren't weren't available to optimize wings to the actual hull it was being attached to, remember the Intel 486 was introduced in 1989, it ran at 16MHz and cost $3-4K. The alternatives were renting mainframe time or using a modeler and tank time to physically test different versions.

Also once a manufacturer had settled on a shape for use on all their boats, it could be trademarked so other manufacturer's were required to develop their own shapes.

More recently the trend in racing boats for very deep, high aspect keels with bulbs on the bottom has made it easier to put relatively cookie cutter wings on them. Being very deep there is a lot less interaction between the wing and hull and the fins for such keels have become very similar. Also the theoretical understanding of what is going on is much better and there are vastly better computational resources available so it is much easier to use a boilerplate fin, bulb and wings and tweak the details slightly to optimize for each particular boat.

For cruising boats this is not the case more conventional fins still need to be used so cookie cutter wings are a lot harder to use. But my understanding is that bulbs provide some of the effects of a wing but are sturdier in a grounding and don't catch lines and weeds as much so there might be a little movement in this direction currently. We'll see over the next 5-10yr.
__________________
A house is but a boat so poorly built and so firmly run aground no one would think to try and refloat it.
SailboatData
Adelie is offline   Reply With Quote
Old 27-06-2013, 10:24   #51
Moderator
 
noelex 77's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Location: Living on dirt waiting for our new yacht to be built.
Boat: Half built Bestevaer.
Posts: 10,619
Re: Wing Keel?

I think unfortunately wing keels are/were often fitted for their marketing,rather than their hydrodynamic, performance.
However lead bolted on the end of the keel is a good way of achieving reasonable performance with a shallow draft. The shape of the lead (wings, plate, torpedo) only makes a small difference and winged keels are often not a bad alternative, mainly because they get a bit more ballast low down

I would rate the biggest drawback as an inability to reduce draft when grounded by healing the boat, also some have a rather flimsy construction of the wings seen on some boats.

The biggest advantage is an effective deeper draft when healed reducing leeway when its needed most, and some reduction in keel tip vortices.

If I had my choice for a cruising boat I would choose a scheel keel, or possibly a torpedo as the ideal shape.
__________________
noelex 77 is offline   Reply With Quote
Old 05-07-2013, 15:36   #52
Registered User

Join Date: Sep 2009
Location: Kittery Point, Maine, USA
Boat: Warwick 46
Posts: 26
Re: Wing Keel?

Scarlet, an Alan Warwick (NZ) designed Cardinal 46, with the optional wing keel which has bigger wings than most, I think.
Attached Thumbnails
Click image for larger version

Name:	Wing Keel.jpg
Views:	1338
Size:	433.3 KB
ID:	63633  
__________________
Spencer
Cardinal 46 "Scarlet"
Ibiza, Spain
ssmith is offline   Reply With Quote
Old 05-07-2013, 16:58   #53
Registered User
 
endoftheroad's Avatar

Join Date: Dec 2008
Location: Key West
Boat: Westsail 32 and Herreshoff 28
Posts: 1,159
Re: Wing Keel?

Quote:
Originally Posted by ssmith View Post
Scarlet, an Alan Warwick (NZ) designed Cardinal 46, with the optional wing keel which has bigger wings than most, I think.
I have those mounted on my outboards cavitation plate.
__________________

__________________
endoftheroad is offline   Reply With Quote
Reply

Tags
keel

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 14:27.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.