Why would sailboat racers prefer a full keel over a fin keel?

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  • Thread starter Thread starter DaveC426913
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  • #31
pbuk said:
In order to offset the heeling moment generated by the wind on the sails, the keel must generate a given amount of lift.
Heeling is caused by the couple created by the sideways force of the sails and the opposing sideways lift of the keel. Heeling is opposed by righting moments caused by the weight of the keel and bouyancy.
 
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  • #32
Some boats do not have a fixed keel, but instead a keel that can be pivoted downward (swing keel) or lowered (daggerboard). These may be weighed if ballast is desired. Fixed keel boats with shoal draft can have a swing keel mounted in a pocket in the bottom of the keel to improve windward performance. This is referred to as a centerboard.

Small sailing dinghies often have unweighted dagger boards that are thrust down through an aperture in the bottom of the boat or leeboards mounted on the side of the hull that can be swung down into the water on the lee side of the boat to counter leeway.

Large ocean racers with canted keels need auxiliary dagger boards to reduce leeway. Additionally, they have two rudders because they are typically very wide in the stern, and when heeling, one center rudder would be raised substantially out of the water, even at a low angle of heel. BTW, the rudder of any typical monohull, when heeled excessively, loses grip and makes it difficult to steer the boat.
 
  • #33
gleem said:
BTW, the rudder of any typical monohull, when heeled excessively, loses grip and makes it difficult to steer the boat.
Pffft. Who wants "typical"... :wink:

1780085623533.webp
 
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  • #34
tech99 said:
Heeling is caused by the couple created by the sideways force of the sails and the opposing sideways lift of the keel. Heeling is opposed by righting moments caused by the weight of the keel and bouyancy.

Yes, I am not sure why I wrote what I did (now corrected) - I was tired after a long day sailing!
 
  • #35
DaveC426913 said:
Pffft. Who wants "typical"... :wink:

This thread is about sailing boats, that well-known monstrosity has no place here :wink:
 
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  • #36
Technically it is a motor sailer. I think it is a MacGregor 26 M. This picture gives a better impression. Did I get it right @DaveC426913?

1780249766147.webp
 
  • #37
gleem said:
Technically it is a motor sailer. I think it is a MacGregor 26 M. This picture gives a better impression. Did I get it right @DaveC426913?

View attachment 372207
Yes. Mine is a 26X. The 26M's sibling abomination.
 
  • #38
pbuk said:
This thread is about sailing boats, that well-known monstrosity has no place here :wink:
OK, It's not a great sailboat, and it's not a great power boat. But it is suitable for it's purpose. Jack of all trades, master of none. Everyone knows this, it just takes one look.

Don't #@%$ on other peoples boat choices, they may want different things than you do. They may have different constraints.

PS: I'd be happy to spend a day out on Dave's monstrosity. But I'd rather go out on my old C&C33 that I sold almost 20 years ago.
 

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