Free body diagram of a sailboat

  • #26
DaveC426913
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The design was from a time when neither forms of protection were in common use (look at the original adverts for such boats). Here's one for the original Centaur. (Do you have a similar reference that you could post, Dave?)
http://sailboatdata.com/viewrecord.asp?class_id=4090

I have heard that it could be solved by tipping the mast forwards by a few degrees.
This is not the first time such an idea has come up. Mast rake on this boat should be 4 degrees.
 
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  • #27
DaveC426913
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Is here an owners association which you can contact for other person's experience with this boat.? If it is characteristic of the design then everybody should have the problems.
Yes, I am in lengthy discussions with sailors on the forum specifically for this boat.
It is they who are making the suggestions of adjustments that I am bringing here for validation.

This page, documenting a test by Roger MacGregor (the designer himself) suggests:
If the boat wants to round up into the wind, unroll a bit more genoa, or let the mainsail out. This will move the center of pressure on the rig forward, and make is less likely to round up into the wind and waves.
http://www.macgregor26.com/photo_ga... winds/photo_gallery_page_4_heavy_weather.htm
 
  • #28
sophiecentaur
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The situation as described poses a problem under really bad conditions as it implies that you need to heave to and can't run before a storm.
 
  • #29
gleem
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Yes, I am in lengthy discussions with sailors on the forum specifically for t
his boat.
It is they who are making the suggestions of adjustments that I am bringing here for validation.

This page, documenting a test by Roger MacGregor (the designer himself) suggests:

MacGregor's suggestions are typical for any boat in heavy conditions. He even suggest that the boat might even have excessive lee helm under certain conditions. Can you ever produce lee helm? If yes when at what point can't you?
 
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  • #30
sophiecentaur
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I don't think the Physics approach will help too much here. After all, even with a lot of computing power and know how, there's still a need for physical testing on cutting edge hydro and aero dynamics designs. So - no shame in a practical approach here.
 
  • #31
DaveC426913
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The situation as described poses a problem under really bad conditions as it implies that you need to heave to and can't run before a storm.
How so? The boat will round up. That's what you want, if you want to stop sailing.
 
  • #32
DaveC426913
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I don't think the Physics approach will help too much here. After all, even with a lot of computing power and know how, there's still a need for physical testing on cutting edge hydro and aero dynamics designs. So - no shame in a practical approach here.
Well, this is what I was afeared of. See post 19. ... and post 1. You guys are expanding the scope beyond answerability.
 
  • #33
sophiecentaur
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How so? The boat will round up. That's what you want, if you want to stop sailing.
I have heard. though, that when conditions are really bad (no personal experience) it may be better to run. But (bad metaphor, perhaps) it's a rock or a hard place.
 

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