Great interview. Main thing i missed was a discussion of what kind of performance tradeoff, if any, he got by going with a bolted connection between fuse and frontwing. He did allude to the advantage being ease of design and manufacturing when discussing the fuse (and im sure price) but he didn’t really mention any drawbacks. I wouldn’t expect a brand necessarily volunteering that in a product pitch, but the interviewer at least could have asked.
I’m looking forward to trying one. Let’s hope kt has a good partner for production that can deliver quality in a timely matter
I’m 100% off monobloc construction as a design concept. Metal is just a far superior material for managing the loads that occur between the mast and front wing. Carbon is superior at being really strong in one direction but that fuse area requires strength in many directions. Metal is just better for it.
I think for the absolute best designed system i’d have to go with Omen(don’t ride it never even seen it in person to be honest). Metal fuses, Bonded to wing to eliminate movememnt AND corrosion in that connection(corrosion being the hard part about the front wing connection because theres more room for water to get in). Metal for the half of the fuse that needs it, carbon for the part that doesn’t. Mast socket is great.
I don’t really understand the f-one, AFS, and now KT style Mast to fuse connection. Seems to me like it takes alot of material out of the fuse at an important point (structurally) and is more hydro drag. I mean the socket connection is really easy to get right. I just potted one last week (broken NL into North AL Fuse) and its tight as a tick. Also, the north front wing connection is that basic ass 3 bolt flat connection (which i’m on the record shitting on in the past) but godd damn if it doesn’t work great. (And i’m brutal on gear and real persnickity about connection movement). I mean maybe that mast connection system is about preventing dirtbags like me from playing with it!
My takeaway is connections and systems and whatever are about the details. How tight are the production tolerances. These things could be M8 Reiforced lego pieces and if the tolerances were good enought it would be fine. If your taking care of the toleranes and the design is whatever its going to be tight. Wing design is really all that matters (and all that anyone going to KT for the KDW is thinking about). The wings are why this is going to be great despite a Basic Bitch connection system and why the new slingshot (even if its the stiffest setup on the planet and assembles just by looking at it) is irrevelent.
Now how ABOUT those wing designs! That concave in the trailing edge camber is WOW! It looks like what made the lift 120 special but more cowbell. Who has the numbers for the whole range. Areas, Spans, Etc.
The omen construction indeed is bombproof. That’s what I’m riding. Zero play after more than a year. Still have to wiggle the foil from the mast every time.
I hundred percent agree with you on the wing design comment. Kane is obviously one of the stars of the industry. I really enjoy listening to him in interviews. He has that magic trifecta of passion, skills and youth. His output is probably more than a team of ten middle aged nine to fivers with mortgages, day care pickups and work from home schedules eating up their bandwidth.
I think they struggle with it because it’s not a good connection for carbon on carbon. It works really well with carbon mast in aluminum fuse, But yeah I’d take this connection as a sign that a full carbon or monobloc is coming
I feel like the F-One/KT/AFS style connection puts more direct roll input to the fuse - rather than just leaning the mast over in a socket, you’re driving the fuse in the direction of roll - to me that has felt like a more responsive setup than pure socket-style connections (came from lift).
After more than 2 years of almost daily use my mast to fuse connections (F-One) are still perfect. No play, no wear, and every wing fits perfectly (which has not been my experience with Lift…).
I’m about 170-175lbs, so not the most demanding end of weight range. So take this for what it is worth, but…from Armstrong to Lift to F-One…F-One is by far my favorite system from a performance perspective.
The deep rear concavity is interesting but not that new. I have a Medusa Pro 669 that also has a pretty deep rear concave, though maybe not as deep as the new KT foils.
However, what was most interesting and I think perhaps the innovative part (I’m not aware of any other current hydrofoil designed like this) was Kane’s explanation of the front symmetrical section. It never occurred to me in designing a foil that one might make it symmetrical. I always took it as a given that the top surface would need to have more curvature to produce the lift. But he’s right that at high speeds, you would need to push the front foil downwards to maintain neutral lift. And of course, that would cause a low pressure spike at the front and increased drag.
So then a big concave/camber/reflex (I disagree with Adrian’s definition of “reflex”) is needed to create the lift. They’ve apparently made it big enough that we can decrease our normal foil size by 20% if Ryan was not exaggerating, thus decreasing drag.
I’m sure this is not an entirely new idea and someone must have tried it for sail racing foils but I would imagine their only concern is high end and don’t really care about low end speed. But perhaps for our wind sports recreation, this may be a great application of this design.
All VERY interesting and now I’m going to wait for the KT foils to be released so I can go demo them.
I’m kind of annoyed that all these developments are being done with 70-80kg athletes and macking ocean conditions. Honestly, we all aspire to that but most of us don’t have that. My local run is a 3min/km bay run with downright shitty conditions by any objective measure.
These tiny foils CAN ride as slow as 3min/km - but they are super draggy at that speed. Unfortunately it isn’t being mentioned. Just because they extend the low range way down slow doesn’t mean you can practically ride them that slow. Its just for initially getting up or digging out of a hole. But it takes epic energy everytime to work out of the hole and up to speed.
And all of this gets amplified for heavier folks.
All this is to say that these foil designs sound great, and probably do work extremely well for the right conditions - but I still wish someone was designing really efficient wings for going slow that still ride well.
Id love to try the wiz. It looks cool and different. I feel like that dihedral would match the swing arc skating around under the rider. Id love to demo one if you know anyone at duotone!
I feel the same about narrow boards. It takes so much energy to stay up on a sup, or pop up with my hands touching each other prone, or climbing on sideways winging… that I’d be better off more rested than on foil quicker!
I was riding an 8’ down wind board yesterday in really small surf and noticed how the swing weight made it such that I just couldn’t generate enough speed to keep what is normally plenty of foil lifting. A small but stable board with a wide chord and thick foil would’ve been really fun!
-that said, if Kane has had as much design input as it it sounds like he has, these foils should work quite well and you don’t have to size down if you’re not pursuing top end speed.
Think about what makes the most percentage of lift for level cruise flight: Low pressure above the airfoil and a higher pressure below it.
I’m shooting from the hip here, but making a wing from scratch it looks like you can increase the pressure under a wing by creating a concave pocket on the underside to slow the laminar flow. Now there’s a pressure imbalance using the opposite of Bernoulli’s principle. I don’t know if 1) The concave creates a braking effect to the laminar flow approaching it, like a type of Tesla valve or 2) The concave itself is creating a pocket of high pressure as water flows through it. Either way, I have a feeling it would be hard to maintain laminar flow after exiting the concave section. So moving that high pressure pocket to the back of the wing lets the flow coming out of the concave simply spill out the back in a flap-shaped termination.
It’s worth mentioning that the first 10-15° of airplane flaps are usually referred to as Takeoff flaps because they add lift and reduce the angle of attack for a given speed by lowering the nose. Combine all that and planes take off in a shorter distance at a slower speed.
The Konrads are sick foils, and there’s another company called One Ocean Australia who make an Axis compatible foil too. That’s all I know about, but it’d be great to get a standard.
I remember listening to an interview with the Air Chair guy and he said all of those foils had a standard mount.
