Addressing Bill Roberts paragraph post of last week "fixed foils won't work...". I've got Doran Oster and Bill both fussing at me now in the same week! I agree that fixed surface-piercing foils are always in a dynamic situation, with everything changing all the time- variable lift, driving force (wind), drag, heeling angle, fear of crashing in the driver's heart, etc....

But this is the reason for the tapered surface-piercing foils as seen in the old Icarus I photos from the 1970s, and now the 36 foot Spitfire biplane foiler from Perth. The question that I see is- can I buld a modern tapered shape that will avoid some of the disadvantages of previous shapes. Bill Roberts and Doran- and Dr. T-foil (Sam Bradfield)- say it's hopeless. BUMBLEBEEs fly anyway...despite what the engineers said years ago. BTW- High speed photos of insect flight are absolutely amazing, with flexible (plastic) wings, superflexible joints and vortices. Well, that nails the name for my next foiler.