Wave oriented hydrofoil

[Starsky]

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I am never listening to anything you ever say again.

[ROLAVI]

Hi

Here is the results of my tests in waves,
I'm very close to Peter's explanation. And like Peter, I dream about hydrofoil in waves (you will never slash a wave like a surfboard, but the feeling of riding waves with an hydrofoil is awesome)

1- I prefer to ride long mast (at least 90cm). For 2 main reasons:
Long mast allows to ride in shallow water with the wings can be deeper in the water
Long mast allows to prevent the board touching the water. When the board touches the water during turns, it stop your turn (as the board starts to be flatter on the water)

2- I love front wing with no anhedral.
Anhedral seems to be good but it is not (except constant anhedral). If you use anhedral only on tips of the wing (with flat part in the center, like the zeeko race wing for exemple, cerbon freeride wing have a constant anhedral) when you turns, the tip of the wing can ventilates more easily when it is close to the surface of the water. Flat wings prevent this

3- I love front wing with thin profil and medium AR
In fact in waves, you have a lot of acceleration and you need to control this increase of power. With a thin profil and medium AR, the power increase is smoother, then you can be concentrated to your turn.

4- I love small back vertical fin. You know there is 2 different back wings: ones with anhedral or dihedral, and the other fully flat. When I use flat wings, for waves I add a 2.5cm height back vertical fin on the back of the fuselage for waves (specially if my front wing is without anhedral). When I ride for freeride, I keep my 4.0cm vertical fin (in order to prevent yaw effect).

When you use small vertical fin + flat back wing and flat front wing, the rotation point of the foil is between the mast and the back wing, which is perfect for turns (the foil turns like a surfboard)

If you use: Front wing with anhedral, back wing flat with no vertical fin, the rotation point is between the front wing and the mast (tacks are easier, but jibes and front turns more difficult, then surf more difficult)

5- I love mast with a smaller cord.
Smaller is the cord of the mast and shorter turn the hydrofoil. 115mm is a maximum for waves (for example, I prefer my carbon mast with a 99mm cord, than my alloy mast with 115mm of cord).

6- I love to ride strapless: when you ride in small waves, usually the water is not deep enough. Then when you turns with speed, you can touch the ground and break something if you keep straps. If you ride strapless, the stress on the hydrofoil is close to nothing because when you touch the ground you fall immediately.

7- I love to ride very small board.
In Waves, I love to ride my 108cmX46cm board (we are in production now). The fact that the board have no nose makes the turns closer. This is due to the fact that the board have no inertia (in fact the inertia center is close to the foil inertia center).
Here below is the green board I use in waves

ride easy
Nicolas

Nice. When can I order the shorter green board? I need a smaller strapless option to my strapped pocket board.

[PD Gorby 67]

The picture with the dolphins is really cool.

Here is an example of surfing a hydrofoil, without the kite confusing things.

https://vimeo.com/91188392

[tegirinenashi]

The picture with the dolphins is really cool.

Here is an example of surfing a hydrofoil, without the kite confusing things.

https://vimeo.com/91188392

Conceded. (The awkward thing is that I saw this video earlier. There is no excuse of not having morning coffee too).

P.S. I asked this question at appropriate venue:
http://physics.stackexchange.com/questi ... ve-surfing

[jespin4845]

I dont care what anyone says, shutting the power off of the kite and riding the non-breaking wave that i thought 7 months ago was impossible to ever catch is fun as hell
Yea its not bottom turns and what not in surfing in a traditional sense, but doing s carves and catching that flow of water is riding the wave to me, especially when ur kite goes slack and u feel like ur laird hamilton in those videos u watched as a kid

[Peter_Frank]

I dont care what anyone says, shutting the power off of the kite and riding the non-breaking wave that i thought 7 months ago was impossible to ever catch is fun as hell
Yea its not bottom turns and what not in surfing in a traditional sense, but doing s carves and catching that flow of water is riding the wave to me, especially when ur kite goes slack and u feel like ur laird hamilton in those videos u watched as a kid

Precisely, very well put !

If anybody doubts whether it is SURFING, they havent tried it themeselves yet...

Anyone who has learned to foil, and doing S carves, knows what a huge impact even a 1 foot wave has on glide and speed and freedom.

So when you carve around in a 1-2 foot wave, you get a huge powerspike in terms of speed and glide, and you can let the kite hang drifting

Even with a relatively big amount of experience, I am still amazed and feels awesome, when you do a sharp turn when powered on the light side, and you feel the acceleration in the turn - you can actually get more "kick" in the turn in terms of power, if done sharp, particulary in really light wind !!!

An awesome and unexpected feel - but everyone who carves/ride waves knows what I am talking about

The power from the wave is in fact much higher than when on a surfboard - because a hydrofoil is much more sensitive and because of the low drag it accelerates faster - which you can feel immediately - AWESOME !

But agree, got nothing to do with regular waveriding, so only time will tell what we find works - doing DTL carves is of course what we try as used to it, and it works great IMO, but it might develop to something else, just like noone really wants to jump much anymore (if used to waveboards), simply boring, compared, just occasionally doing a megajump just for the feel and knowing you can - nothing but that

Regarding fuselage lenght or stabilizer size (or rear stabilizer V/upsweep or not).
If you have a short fuselage or no stab, you can "twist" the hydrofoil easier, yes.
But this is not turning IMO, just sideslipping which feels so wrong.
To have some stab area/length gives you the right driving surf feel - just like if you try to ride waves with a finless skimboard - it can turn on a dime it seems, but actually it does not turn at all and feels wrong
So some area is important for the "surf" feel IMO - I think most knows what I mean.
This is why we see most race oriented hydrofoils having no stab area at all (or no anhedral/dihedral rear stabilizer) - as it gives the lowest drag and you can turn tight on tacks, instead of the good surf turn feel many of us likes.

Also, the mast and COE has to be quite aft (almost the same thing) - meaning the mast can not be just above the front wing, as then you get a stiff and not driving foil at all, very wrong - IMO almost the same as having no stab or no rear wing up/downsweep/dihedral

So being able to twist the board as fast as possible, is IMO far from what gives you the best driving surfy feel in the turns/carves.

Of course, there might be a point where it will feel too stiff if too stable in terms of yaw - I dont know - but havent met that wall yet...

Narrow wings versus bigger wings ?
Disagree that big wings in terms of span, can turn just as fast - I experience the opposite.

Yes, when you are learning, a narrow wing is way easier to turn, and later you learn to turn the higher span wings tighter too - but it is WAY easier to turn a low span wing fast, and even more important - what I mean with "bubbles" is in tight carves, the bigger span will often have some or a lot of ventilation/cavitation of some kind - easy to spot on video when doing 360s on different wings.

I am a firm believer that it is better to avoid these bubbles if you can - eventhough often the wing dont really stall it seems, but it does not seem right
Difficult to explain, and maybe nobody knows what I mean ?

Still, an awesome thread this is, and the very reason I love hydrofoiling, is the ability to play and feel even the smallest waves when out carving around

PF

[ahmthai]

Who out there has actually ridden a short mast (<60cm) hydrofoil in the waves? Please share your experience.

-Andrew

[revhed]

And as for flying the wings deeper in "cleaner H20" less "white water" to avoid drop out with a standard length STRUT?
R H

[ronnie]

It might still be early days in hydrofoil development.

If someone can get the 2 positive lift wings in a canard configuration working, where the wings are close together, it might be a good wave setup.
http://mypaipoboards.org/hydrofoil/paip ... foil.shtml

[Starsky]

Who out there has actually ridden a short mast (<60cm) hydrofoil in the waves? Please share your experience.

-Andrew

There was a thread on short masts for learning purposes. The clear consensus is that they result in more touch downs in anything less that flat water. That's tough to accept for anyone looking to eliminate touch down altogether. I understand your point regarding the shorter arc, but also understand that a more standard length geometry can carve at a harder angle without wingtip breach or board rail touch down. Kind of quick vs hard carve. Surfboards vary drastically for different styles and conditions, I would imagine foils can too.