I have added drag components for the sail and the windage.  I also looked at the L/D for the rig with 12m masts but considered both 40sq.m and 50sq.m.

One of the interesting features that comes out of this is that the boat makes better VMG with 40sq.m of sail compared with 50sq.m:

The 50sq.m gives higher speed but at lower angle to the true wind by almost 5 degrees.  The 40sq.m is slower but at higher angle such that the VMG ends up higher.

These speeds to windward are much more realistic now that the additional drag components are taken into account.  

With 50sq.m on 12m masts I cannot get the Cl above 1.  With 40sq.m on the 12m masts I can get Cl of 1.1.   The top speed reaching is also a little faster with the 40sq.m rig.

Of course these results are only considering one hull and assume all load carried on that hull.  It is not a complete VPP that caters for shifting of displacement between hulls.  

For light weather performance there is likely to be advantage in going to taller rig.  The efficiency of the rig has a huge bearing on the windward ability and rig aspect ration is the key determinant of rig efficiency.  You may be able to improve span efficiency by having sails close to deck.

Rick

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