just saw pics of your flex tail edge board,it looks ,uh, interesting. Definetly not normal. I like that. Nice to see some one thinking out side the box. Can we get some details maybe.
Ill tell you a secret... that flextail edgeboard is only about 9" long... photographed on a piece of white paper taped to the hood of my pickup. Its a scale model built with high density PU architectural foam, laminated paper and wood glue, computer circuit board, bondo, spray paint, etc. AND the hopes of generating a bit of fresh discussion. It scales to 6-0" x 21" w/longer and shorter applications to stand, kneel and prone. Its not a new idea or original with me. I simply couldn`t afford the time and money for the same board as a full-size project, and wanted to share an idea in some way other than by writing or drawing. I believe this type of board could help resolve a number of nagging issues common to conventional equipment. Consider that the board in the photos could be built with less tail kick, so I designed it with what I thought would be the maximum deck angle and dihedral. Speed, maneuverability, flexibility AND adequate rear flotation? The answer to that question still awaits. As with most flexible equipment, the big challenges are construction and tuning. Dale
When I first saw it, I thought it was showing the tail in flexed and unflexed positions… a double exposure kind of thing maybe done on a computer. Now I can see that that the spoiler looking thing is in fact a rigid component to limit the flex of the lower part. I hadn’t even considered the added flotation, etc. Pretty far out Dale - I like it!
Dale, is this a similar concept to John Kelly’s hydrohulls with perhaps a lot more tail kick action? Perhaps a shortboard version? -Rob Olliges http://www.surfresearch.com.au/00000190.html 
Rob, Its an old idea that deserves to be explored. George Greenough has been using a similar design on his carbon graphite sailboards for many years... hes described them as “spoons to stand up on.” Think about that! The basic purpose is to have both the speed of a flat-rockered tail and the wide range maneuverability and control of a tuned flex tail. The rigid (foam) kicked tail limits the range of flex, and provides rear buoyancy as well as the means to stand on the tail without inhibiting the torque/flex action. Nice photo of John Kellys board! Thats another old idea deserving an in-depth article. John took the chine and strake concept (used extensively by George Greenough), and applied it to the tail instead of the rails. Such fascinating stuff. Dale
There’s an OK picture of an unfinished Kelly hydrohull blank in Vol.4 #1 (I think) of Surfer’s Journal as well as detailed descriptions in his book Surf and Sea. Rob Olliges