Select to expand quote
mathew said..Chris 249 said..
As I tried to make clear, I completely understand why people choose to have lots of sails and as you said it's up to the buyer, but the point is that the claim "modern sails have wider wind ranges" has been made for decades on end and yet there seems to be no evidence that it's really happening, or that modern windsurf sails have a wide range compared to other sails.
I think what you are observing is a reasonable assessment based on the evidence you presented. But I dont think it is accurate.
[ You noted "decades" which implies 80's to 90's era. In that era camber-inducers were only just invented by Gaastra. Full-length battens were still flimsy fibreglass or even wood. ]
A 6m slalom sail from that era could be used [ obviously depending on body weight ] from about 8kn to about 22kn. It didn't really matter what board you used because the sail didn't generate much top-speed. Due to their shape, they were typically quite powerful on the low-end, but sail deformation limited their top-end. The sail-deformation limited their use.
A 6m slalom sail from nowadays typically doesn't have good low-end ( its why formula-sails were invented because _area_ is key ), you use them from about 12kn. Those same sails - even a freeride sail - is quite capable of being used in 35kn of wind. The sail doesn't deform much at all - the limiting factor is typically the person's ability to sheet-in.
I agree that sail deformation limited the top end with the old sails and that the new ones have a vastly better top end. Manufacturers still seem to try to sell sailors just as many sails to cover the wind range. As your figures indicate, a lot of what it gained in top end handling with modern sails is lost due to their lower power at the bottom end.
I can't completely agree about your wind range figures since the wind range you quote for an ancient 6m slalom sail is way out of what I would have used at that time, and since I was top 20 at the slalom world titles at the time I wasn't particularly shyte. No one at the worlds or during the Aussie pro circuit at the time (which included Robby, Bjorn, Anders etc) would have used a 6m slalom sail in 8 knots because the lower wind limit was 15 knots and even in that a 7.8 or perhaps 7.3 was the standard sail.
Top end deformation and C of E shift were a problem, but that is to a significant extent a matter of technique, harness lines and back hand strength. Where those old sails did lose out, as we agree, was by having high aero drag that limited their top speed. I had an ex Pete Cabrinha Gaastra team 7.3 or 7.8 custom with foam/glass or carbon sandwich battens and something like 6 camber inducers and it, and similar sails, actually seemed to have amazing stability - at the cost of having a tight leach and deep upper camber that reduced the top-end speed. It would never make it as a production sail because it was also extremely unforgiving through gybes, although personally that suited my style very nicely.
I think essentially it's an issue about how we define range. We can have different (but equally valid) measures. Those of us who have done a lot of sailing on various OD longboards have spent a lot of time looking for power in light winds and practising holding onto a sail far over the top of its normal range, so our feeling for range is probably very different to that of other people.
I'll also say that I'm unsure how many people these days use a 6 in a true 35 knots. That is hitting well over 50 knots in the gusts. In such winds, people find it difficult walking, the water is covered in spume (not just white caps), things ashore are breaking, etc etc. I sail Sydney-Hobarts where we have sophisticated wind instruments so spend a lot of time getting real windspeed info and with respect, what many people call 35 knots is a wind that may hit 35 knots for very short times at the peak of the gust. That is actually a true 20 knots, by meteorological definition. Some people may be capable of using a 6 in a real 35 knots, but not the average sailor in what I would call normal conditions, with normal chop and gusts.