juanpasala wrote:
For?
Would you care to elaborate?
All hydrofoiling. Me personally for waves, I see huge benefits for ventilating/cavitating. More efficiency is always good too. It means smaller more capable foils, better upwind, faster. The design of most foils makes no sense logically. Having another surface produce negative lift is just stupid. I get you could think you need an airplane style setup under the water, but if airplanes could move their center of gravity like we can they wouldn't need control surfaces either.
ronnie wrote:From what I read, they don't pump as well as regular foils
But is that particular to the concept or just the designs so far. If you look at the design of the Spitfire, one it is quite small compared to the best pumping foils at 2500+cm2 and two it has squared off low AR wings, which would be less efficient. Pumping is all about efficiency and lift? Or is there something else? I am waiting for the monofoilers to answer that.
I remember Nicolas explaining that a canard foil was much harder (way more iterations) to develop than a conventional design where pretty much any characteristic from the front wing can be mitigated with adequate stab tweak.
From my own experience, with a limited number of foils in my background, the main difference I see in terms of pumping between the Spitfire XXLW and the GoFoil Kai, both of similar size, is that when you deweight your front foot on the GoFoil, the whole board rises, whereas the SpitFire requires an active push from the back alongside the front deweighting to get the board to rise up. Deweighting both front and back makes the board rise with the goFoil, whereas it doesn't do as much with the spitfire. It tends to stay neutral or drop down. That is very obvious when bailing out, which is an extreme case of deweighting! One shoots in the air, the other tamely drops.
So pumping a canard, or at least this canard, requires a slightly different technique, with more pushing at the back while deweighting the front. I'm sure with extensive practice this is possible to achieve, but it is different, and arguably harder.
So there is both different design and use principles. It seems just not enough people ,both designers or users, have crossed that valley to find if it really is greener.
I guess there is a well established conventional design, with many followers, and the designs are mostly about refinements of that design. And venturing out of that model is more uncertain in terms of results for your R&D investments, and even if you obtain good or better results (as I believe the spitfire does), then there still is a massive task at hand to convince users that your unconventional design works better. That, to me explains why so few companies go for that.
The pumping factor is not that meaningful for kitefoiling. I switch from one to the other easily and it only takes a few minutes to find my marks again. A carbon SpitFire, with buoyant wings, would probably incite more high end users to go towards that design. I must admit that when paired with a big floaty board like the Scrambler, the weight and lack of flotation of the spitfire make waterstarts quite technical. So the GoFoil tends to be my typical go to option for that board. On other decks, this matters less, and the bulletproofness, performance and inherent safety of the spitfire is the way to go in some contexts.
I've had my eye on the Spitfire for a year or so, to try and learn foiling on one. I like that it requires more back foot pressure and inherent safety. Has any tried learning on one?
I did teach my ex and our son with the spitfire xlw, and it went pretty well. Standard issues with handling the gear, walking to deep enough water, positioning the board for waterstart etc, which are the same with pretty much any kind of foil, maybe harder with heavier ones, not sure. But past that initial stage, the first flights went well. I'd definitely recommend that for learning.
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