Interesting discussion comparing Harryproas to trimarans.
A 12 m (39 ft) Harryproa and a 9m (28 ft) Dragonfly trimaran with the same weight and about the same sail area will perform quite differently depending on the conditions.
The tri will be faster in little wind due to its much lower wetted area, slightly more sail area and taller mast (more wind higher up). I am comparing the schooner proa to the touring Dragonfly 28. Downwind the Dragonfly can fly much more sail area and there will be no contest
As the wind increases, the proa should catch up and become faster due to its longer waterline length, and as you say, it will not have to reef as early.
I can only guess at which speed performance will be equal, say 5 knots boat speed upwind or reaching and 8 knots downwind.
I am now assuming the sail shape and sail/mast combination is equally good on both. I also assume we will never sail dead downwind, because then the aft schooner sail will blank the forward one.
However, the first assumption of both boats having the same weight, may not be correct. Rob suggests an empty weight of only about 800kgs for the Ex40 which would be about half the weight of the Dragonfly. Maybe more equipment is included in the Dragonfly figure, but I guess there will be a significant weight penalty for the Dragonfly anyway.
Just my 2c
Rune
http://www.multihullsolutions.co.uk/Dragonfly28.html
the only was that is standing headroom is if you are 4 ft tall
Im not dissing the boat, I know they perform very well and the configuration offers workable interior volume not available to cats in this size bracket until around 30ft or more. Like the idea of the stepped hull and I think thats part of its secret in offering a decent accommodation and a top class turn of speed. Short forays offshore?, not with me in it.
Ultimately though, on the same weight with the same sail area, a Denney Proa can hold its sail area longer as winds increase, and I expect the longer lee hull will pull more speed. If its still a matter of comparable accommodation there might be a compromise or two there but I am optimistic that features such as privacy could be better afforded, just dont expect a walk around cabin.
Posted by: ru-eno@online.no
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