Hi all, i am Stefano Basso from Italy, i am sail designer of wingssails, sails the world's most compact, I created the SUPER COMPACT SAIL DESIGN CONCEPT
this is the wingssails speed special 5.6
forum.windsurfing.nl/viewtopic.php?f=16&t=13868245
for more info
Stefano Basso facebook profile
WINGSSAILS group profile
Wow, I've never seen anything look like that before 
Just a question, is batten number 4 a bit too short? It looks like it could do with a bit more tension.
Be interested to hear how it performs 
Jeezuz, talk about violating every principle of good design, especially K.I.S.S.
Your sail looks Frankensteinian: an ad hoc conglomeration of band-aids upon band-aids desperately trying to patch over the absence of any real comprehension of the relationship between luff-curve, mast-curve, tension distribution, seam shaping and twist.
I remember, as a grommet, reading an interview with Phil McGain in 1987 or so. He was asked about his design process, and his answer was etched in my mind from that moment on: "Take the SIMPLE designs that are working well and refine those designs." You could do worse than to meditate on those words. Good luck.
Hi nebbian, thank you, here are some photos of the sail in action.
the sailor is Jan Walters from Holland
Setup:
Fanatic Falcon Speed
Caspar speed 25
Wingssails Speed Special 5.6, luff 397, boom 155.
Conditions:
Den Helder, het Kuitje. Flat water, angle about 120 degrees, gusts 24 knots.
Jan Wolters:
Sail feels suuuper easy. Easy to handle, especially upwind.
Very light in the hands. But, luckily, it's still powerfull. No problem with planing at all. Also enough drive downwind.
Almost never sailed a sail that handles and sails this light.
average speed 36knots - 66.6 km/h
top speed 37knots - 68.7 km/h
Hi nebbian, this is the SUPER COMPACT SAIL DESIGN CONCEPT:
THE MOST COMPACT SAILS IN THE WORLD
WINGSSAILS PRESENTS:THE SUPER COMPACT SAIL DESIGN THE MOST COMPACT SAILS IN THE WORLD by Stefano Basso Wings sails presents the super compact sail design concept It 's a design concept that involves sail mast and boom, that is, the rig. The goal is simple, reduce the rigid parts that make up the rig, analyzing the points: - Reduction of the length of the boom - Reduction of the length of the mast - Reduce the number of battens The result: - Sails lighter - Rig lighter - Increased top speed - Improved acceleration - Increased Maneuverability - Lower costs The unique design of Wings sails allows for super compact sails but with well proportioned lines and elegant. No sails with stubby lines
Di: Stefano Basso
djdojo,
Man , what is your beef???? Here is a bloke willing to give it a go. Puts money and effort into trying some ideas and all you can do is bag the crap out of him.
I think it's great we have people in this sport willing to give it a go, who cares if the first attempt may not be absulutely perfect, his next will be better. Good on him and it should be encouraged.
How has your ultra negative post contributed to our great sport???
veramente bella Stefano ! forza ITALIA !! 
spero che arrivano qui !
see i can spell ;-)
Hi Stefano, I am italian too but I live in Bermuda.
Great to see some 'italians' are still applying in this sport.
Anyway, how can we order or evaluate your products?
my 2009 5.6m race-sail is 432cm luff, 180 boom, so this sail with 396 luff/155 boom is quite different in design.
with a much shorter luff the power is closer to your body so in theory should be easier to hold on to in stronger winds and feel lighter.
the very short boom should increase stiffness.
the foot of the sail looks cut quite low, i can see the end of the bottom batten dragging in the water not to mention my toes in strap hitting foot of sail.
concept is great,love to try one out.
djdojo, Communication Skills Coach.... hmm...
Not sure if there are any advantages in Wingsails 5.6 over a Severne Reflex, Pryde Evo or any of the other good speed sails but at least he made a much better effort showing off his skills at sailmaking than you did in your choosen field.
If this is a backyard effort, then my apologies for such a brutal critique, but if this is a serious designer, then perhaps a provocative critique might prompt some better ideas.
If I strip back the gratuitous metaphors, my message might turn out something like this:
It looks a bit like a triangle of high tension from the clew to the front of the third batten to the foot, with much less tension within this triangle (for which batten load can only compensate so much), and the roach area just floppy. While this may create an even progressive twist in a static situation, it is unlikely to retain that continuity of twist and shape distribution (and therefore stability of centre of effort) through gusts and over chop.
Having lots of bits and pieces of battens and tack straps and stuff can get the static shape where you want it, but only by a smooth integration of mast and batten curves and loads can you achieve a rig that responds dynamically in ways that self-organise to make the most of gusts, lulls, and bumps while giving the rider a smooth and controllable ride. This self-organising responsiveness has been the holy grail of race/speed sail development since Bruce Peterson and Dave Russell hooked up with Gaastra and their ADTR contraption in the late 80s and coined terms like "free-leech" and "progressive twist" as they started to attend to the dynamic aspects of their designs.
There are now 20 years worth of examples of ways in which designers have played with these factors with evolutionary steps. The core structure is the same: circular carbon mast, monofilm sail body, wider-than-mast luff sleeve, fiberglass battens, plastic camber inducers and a boom to hang on to. There have been no revolutions in the past twenty years, just refinements of this basic model. The recessed clew is a standard now but has been in and out of vogue for ages. Hot Sails Maui had them in the early 90s.
The design ideas evident in this "speed special" cannot be defended on the grounds of progressing the sport, because there is nothing new there. Either bring something radically new: (a la footstrap, camber inducer, carbon spars, high aspect fins), or refine what is already kicking arse.
Perhaps this is more constructive than my first post, perhaps not. Perhaps if this had been in the general forum under "look, I made my first sail!" I would have been more encouraging, but it was made as a post from a commercial sailmaker in what I've previously perceived as an elite speed forum. If my perception has been inaccurate, I apologise.
To those who red-thumbed my second post in this thread, was it because you were still cross with me for my first post, or was there something about the second post that was offensive in and of itself? Serious question, as the objections to the first post were pretty clear, but the second?
Clearly my tone in the first post was out of line, and would perhaps barely have been in order even if the sail in question had been made by Kai Hopf and he'd asked for my considered opinion in private. For this I'd like to say sorry to Stefano and others who were offended.
To those who are seriously interested in going faster than 50 knots, a rigorous discussion of design principles and examples is surely desirable, no? We trade rougher blows than this in the kiting forums all the time (even with posters whose mother tongue is not English), and for those who search beyond the rhetoric and chest-thumping there are often valid insights to be had.
Stefano, would you like discussion of your sail's design, or did you just want to show it to us? What are your goals as a sailmaker? Fun, personal satisfaction, commercial profit, 50knots?
I just watched an episode of Big Bang Theory, and your post sounded just like something Sheldon would say
It can be easy to criticise...Green thumbs to someone having a go at designing and putting his money into the sport. Red thumbs because the "communication" was a put down...I perceived it that way (and it appears others did too).
A bit of diplomacy goes a long way in my book, regardless of whether you are right, wrong or indifferent.
I take back the diplomacy...and am going to keep it simple DjDojo - Put your money where your mouth is. red thumbs rule.
