----- Original Message -----From: bjarthur123Sent: Saturday, May 28, 2011 3:09 PMSubject: [harryproa] Re: Swing-wing rig....junk"in actual fact" implies you have quantitative data. to me that means two boat testing. have you compared the favored and unfavored tacks in this way?
ben
> My junk rig has an airfoil shape cut into the panels, with a draft of 1/3 the chord length. A junk rig with an airfoil shape is essentially the same as a big, modern square top mainsail. The only difference really is that the sail does get pushed around the mast on one tack....
> But think about this. On the "favoured" tack with the mast to windward, the sail will set a great shape, but the mast will be exposed to the wind and creating drag. On the so called less favoured tack, the mast is hidden in the shadow of the sail, and creates very litle drag. So in actual fact, there is no noticable drop in performance due to the contact between the sail and mast. Sure it looks a little weird, but who really cares?
>
> Also, the leading edge of a sail is very sensitive to turbulence, and a marconi rig with a mast right at the leading edge of the sail will hurt it's efficiency big time (unless the mast rotates), whereas a junk rig will not.