Hey Mike,

 

Thank you for taking the time to help me out.  I value anyone's actual experience over my rationalizations.  I've never seen a Proa in the flesh, much less sailed one.  Here are some of my rationalizations... please point out anything that is wrong.

 

In my brief, I state two configurations... racing and cruising.  The idea being... if I was trailering to a race, I would unload the "cargo" in the lee hull.  Similarly, if I was cruising around and "found" a race to play in, and if I sized up the competition, I could unload the "cargo" at the dock and go have some fun.  That leeward cargo includes, most of the potable water, all fuel, portable generator(s), some of the battery bank.  I'm looking at electric motors so the battery weight is sizable.  It also includes toys like kayaks, bikes and general "junk" that any couple gathers in the attic.

 

In race mode, we'd be on top of it all the time so getting caught aback shouldn't be an issue.  In fact, in light airs (in a race) I'd plan on running as a Pacific and freek out the competition by tacking and/or shunting at will.  In Pacific "mode" as you suggest, I'd more readily fly the long hull (old lee hull) and remove its surface drag.

 

When running conservative... in cruise mode, the leeward righting moment is 170,000 ft-lbs.  To windward, its 57,000 ft-lbs (33% of leeward).  So I would have had to be running pretty hard (more than 33%) before the shift to be an issue.  Also, its my understanding, that the EasyRig weather vanes in an aback situation.

 

Although I have not decided, I am also looking into doing wings instead of an EasyRig.  In that case, they will not use sheets, but will have attached rudders controlling their angle of attack.  They should wheather vane and eliminate any possiblity of going aback.

 

I am concerned that I'm missing something fundamental.  Besides the possible lighter weight of the leeward hull, is there anything about the sail placement (HarryProa vs Atlantic) that makes aback more sensative on an Atlantic?