Apart from the obvious draft differences. Would anybody be able to advise me on the pros and cons of both keel types. We are loking to buy soon and are looking at all options.
Regards
Al.
Fin verses Wing
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ash
- Yellow Admiral
- Posts: 1713
- Joined: Tue Mar 01, 2005 12:14 pm
- Boat Type: Moody 346
- Location: Tarbert, East Loch Tarbert, Loch Fyne, Scotland
Keel Types
Hi Al
By 'wing' , I assume you actually mean 'twin' - often wrongly called 'bilge'
I would expect a 'wing' keel to be a modern developement - a fin with a horizontal wing on the bottom. This adds mass at the lowest, most effective position to improve righting moment in the same way as a bulb. The wing also makes the water flow across the keel more efficient by preventing spill around the bottom. An efficient keel reduces leeway.
'Twin' keeels are primarily used to allow the boat to take the ground without any complicated devices to stop it falling over. By splitting the weight into two keels, they can be made shallower. 'Twin' keels are considered less efficient than fin, but that is only because they are usually shallower. A twin keel of the same draught a fin could actually be more efficient.
Twin keels which are bolted on, as opposed to moulded into the hull, can be splayed outwards, can be toeded in, and can be asymetrical. Splayed keels mean that when the boat is heeled, the leeward keel is vertical, increasing and maximising the draught. Toed in keels reduce leeway. Asymetrical keels give more lift to reduce leeway.
Twin keels will initially be more tender as the weight of the two keels balance each other out, until the boat heels so that the leeward keel is vertical.
As with other things in life, its 'horses for courses' - it all depends on where you intend to sail - whether the boat is small enough to trail - whether you intend keeping her on the hard at home during the winter, etc.
Despite what I've said above, unless other considerations took a higher precedence, from a sailing point of view I would pick a fin.
Regards
Ash
PS I started sailing on a 17' twin keeled Leisure 17, and now sail a 27' long keeled Vega.
By 'wing' , I assume you actually mean 'twin' - often wrongly called 'bilge'
I would expect a 'wing' keel to be a modern developement - a fin with a horizontal wing on the bottom. This adds mass at the lowest, most effective position to improve righting moment in the same way as a bulb. The wing also makes the water flow across the keel more efficient by preventing spill around the bottom. An efficient keel reduces leeway.
'Twin' keeels are primarily used to allow the boat to take the ground without any complicated devices to stop it falling over. By splitting the weight into two keels, they can be made shallower. 'Twin' keels are considered less efficient than fin, but that is only because they are usually shallower. A twin keel of the same draught a fin could actually be more efficient.
Twin keels which are bolted on, as opposed to moulded into the hull, can be splayed outwards, can be toeded in, and can be asymetrical. Splayed keels mean that when the boat is heeled, the leeward keel is vertical, increasing and maximising the draught. Toed in keels reduce leeway. Asymetrical keels give more lift to reduce leeway.
Twin keels will initially be more tender as the weight of the two keels balance each other out, until the boat heels so that the leeward keel is vertical.
As with other things in life, its 'horses for courses' - it all depends on where you intend to sail - whether the boat is small enough to trail - whether you intend keeping her on the hard at home during the winter, etc.
Despite what I've said above, unless other considerations took a higher precedence, from a sailing point of view I would pick a fin.
Regards
Ash
PS I started sailing on a 17' twin keeled Leisure 17, and now sail a 27' long keeled Vega.
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Nick
- Admiral of the Blue
- Posts: 5927
- Joined: Sun May 12, 2002 4:11 pm
- Boat Type: Albin Vega 27 and Morgan Giles 30
- Location: Oban. Scotland
- Contact:
Wing Keels
These are less common, particularly on older boats, but there are some. We have a friend with a Sigma 33 (masthead cruising version) which has a wing keel. The boat was once grounded in a F8 in the Monach Isles and stood upright on the wing for 24 hours after being abandoned. When the anxious owner went back to salvage the remains only the rudder was damaged. He believes that the wing - in addition to being an efficient way of getting the C of G very low and increasing the righting moment for a given amount of ballast - helps to dampen pitching in steep head seas.
Disadvantages are that the boat will probably be slightly less close-winded and if grounded cannot be heeled to help get her off.
For a detailed discussion and points of view re. fin versus wing keels see HERE - it's on the Catalina 34 site . . . the boat comes in both varieties.
Disadvantages are that the boat will probably be slightly less close-winded and if grounded cannot be heeled to help get her off.
For a detailed discussion and points of view re. fin versus wing keels see HERE - it's on the Catalina 34 site . . . the boat comes in both varieties.
- Nick 
