Re: [Amel Yacht Owners] Weight distributuion


James Alton
 

Bill,

   Thanks for your input and opinion.  It seems that most of the Amels that I have seen to date seem to be down by the stern at least some but on the other hand I don’t hear many complaints about handling or performance.  Perhaps as you allude the Amel hull is not too sensitive to fore/aft trim changing those parameters?    That would certainly be a desirable trait to have on a cruising hull but not something that I have studied or thought about much so far...   You make a good point about the shallow bows of some boats  being must more sensitive to fore/aft trim changes than the deeper Amel bow.  The (by todays standards) relatively sharp and deep bow entry of the Amel is one of the things that I really like about the hull design as it seems to eliminate much of the pounding as compared to a more flatish entry.

    I like the way my boat handles the way she is  (very slightly down by the stern) and want to do my best to not mess that up by altering the weight distribution and changing the fore/aft trim of the boat in an unfavourable direction.  My testing in light conditions with no sail up shows that the boat has only a very slight tendency for the bow to blow off which to me means that the boat will be under control at low speeds while maneuvering and so far that is how it has worked out.  The bow also does not blow off after a slow tack as many other boats I have sailed do which is important in the event that I am ever forced to tack in a critical area, perhaps with no engine as a backup.  I found that while coasting along with no sail up I could continue to turn the boat towards the eye of the wind down to about 1/10 of a knot of boat speed in light air conditions.  I feel that this type of balance is really nice in gusty conditions since the boat tends to not be directionally affected much by the gusts giving me one less thing to worry about.  Depressing the stern further would increase windage forward and reduce it aft while also moving the CLR aft, all of  which will combine to increase the tendency for the bow to blow off at low speeds, hence my concern.    On the other hand the windage of an arch would be a little like having some mizzen out and tend to hold the bow up an might compensate for some or even all of the fore/aft trim change due to adding the arch.  I guess one could try to work some of this out mathematically but sometimes  the only way to know for sure  is to make the actual change and live with it.  So this is why I am trying to gather as much information as I can before committing to a particular arch design,  thanks for your contribution even it if is just speculation.   

Best,

James
SV Sueno,  Maramu #220

On Dec 16, 2017, at 1:59 PM, greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:

James,


I could speculate about the effect of minor changes in fore and aft trim, but it would be just that--speculation  Some boats have a very carefully calibrated bow immersion, any deeper and they wallow, and any higher they come out of the water.  I really don't think the Amel hull design is such that the line drawn on the plans is clearly better than one a tipped a little one way or the other.

When we first bought Harmonie, and she was empty of gear, she was on the waterline as drawn by Amel within a cm or so.  She rides a bit stern heavy right now.  Nothing in the way she handles indicates she has a serious problem with that.  Her helm balance is easily adjusted with sail trim. I can work her upwind easily, and she is well behaved overall.

< /div>
However...  all that said, I am not now and never have been a racing sailor tuned in to the really finer points of tweaking a boat.  I work hard and study to make her go upwind as best as I can, and pretty much figure everything else will follow along once I have that dialed in!

Bill Kinney
SM160, Harmonie
Fort Lauderdale, FL
 


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