Contact   Imprint   Advertising   Guidelines

Monofoil or "riding stabless", setup and riding

A forum dedicated to Hydrofoil riders


User avatar
Øyvind
Rare Poster
Posts: 27
Joined: Thu Sep 21, 2017 11:00 am
Kiting since: 2010
Local Beach: Najomtien, Thailand
Favorite Beaches: Najomtien, Thailand
Style: hydrofoil
Gear: BRM kites, Kanaha board & Ketos foil
Brand Affiliation: None
Contact:

Re: Monofoil or "riding stabless", setup and riding

Postby Øyvind » Tue Aug 28, 2018 4:27 pm

Hi.

I tried "stabless"
phpBB [video]

I like it, it is very agile/responsive to any turning, and more smooth & fast.
I did find it hard to switch feet around, because now board very quickly "Nose-dives", as soon as my feet are off the board.
Any suggestion how to make the Board go more "flat forward", or maybe even "Nose-up" a little, when the feet are off the board ?
I see Horst talks about "shiming inbetween strut and wing", but I dont quite understand what this means.

Also, would it be a good idea to mount the wing straight on the Mast, ( no fuselage ) ?
( and also move the mast forward of course, so the wing stays at the correct position )

Tips and suggestion highly appreciated.
Thanks,
-Oyvind.

User avatar
Peter_Frank
Very Frequent Poster
Posts: 8809
Joined: Wed Oct 16, 2002 1:00 am
Kiting since: 0
Brand Affiliation: None
Location: Denmark

Re: Monofoil or "riding stabless", setup and riding

Postby Peter_Frank » Tue Aug 28, 2018 4:46 pm

Moving the mast forward will not change the pitch stability, and it will most likely turn like shit (like normal or even small stabbed foils do when mast moved over the wing) :wink:

A wing with a pretty normal profile (camber/curve) will never be stable without a stab, it will either pitch up or down when "unattended" like when you leave the board for a while.
"Unstable", and it will usually pitch forward yes :roll:

Then there are some "tricks" to avoid having the stab, and still some or even good stability.

If a wing is swept back, and even better add some washout, then you can make a lifting profile stable again :thumb:

If a wing has an "S" camber, it will have less overall lift yes, but it WILL have more lift than a symmetric profile, and be stable again :thumb:

These are the two known ways to make wings without a stabilizer stable, and used a lot in aviation.

8) Peter

User avatar
Horst Sergio
Frequent Poster
Posts: 406
Joined: Thu Oct 29, 2015 10:57 pm
Kiting since: 1999
Favorite Beaches: Every puddle I can find in Central Europe,
the unpopular the better
Style: SLOW STYLE & stuntkiting
Gear: Just MONOFOILS, no training wheels ;-)
OZONE chrono, FLYSURFER sonic²/r, CONCEPTAIR wave
Brand Affiliation: KITEJUNKIE.com 's prank monkey
Contact:

Re: Monofoil or "riding stabless", setup and riding

Postby Horst Sergio » Wed Aug 29, 2018 9:43 pm

@Oyvind:
:thumb: greatest respect, very nice to see you riding strabless stabless, which is extremly difficult. Did you realy even do a strabless stabless jibe. That's a First, not Philippe and not me have been able to show this. :thumb: :thumb:

As Frank said there is nothing to do about that the board will immediately nose dive or even backflip if it is riding for itself.
About shiming this is something you have to feel for your personal setup ans speed window: If you feel that the nose is going down to much at high Speeds and you have to angle your back leg, this means you have to shim: increasing the angle inbetween wing and board to get boards nose higher and therefore haveing a compfortable riding Position with both legs nearly straight.

To prevent nose dives during jibes,
there is something special about monos: Right in front of the feet switch you have to increase the pitch significantly, so that the board stays nose up for this Moment before you land again on the board and push it down … lets say this is the technique for straps which I need to get my front foot locked again, could be different with strabless.


@Frank:

Yes, I had a discussion about improving monofoil wings with the kite designer from flysurfer Armin, who also tried and liked it. I think the conclusion was:
You are right for traditional airplanes with load inbetween wings that tricks like swept back wings, S curve camber and offset are helpful for flying wings.

But if the load point is 2 or 4 times the wing span above the wing, all those tricks could be worthless and only regulation as human brain can do the stabilisation job.


By the way, even if high AR monos are still not the basic idea of monofoiling, but it is not just insane that they are also rideable, but on top what can be done with them :D
http://kiteforum.com/viewtopic.php?f=19 ... 7&start=10

ronnie
Very Frequent Poster
Posts: 3804
Joined: Sun Jul 24, 2005 6:39 pm

Re: Monofoil or "riding stabless", setup and riding

Postby ronnie » Fri Aug 31, 2018 10:23 am

Not sure if this is a wing and stabiliser, canard, or monowing. Its different!

https://yt3.ggpht.com/a-/ACSszfG_4FNxcN ... ff-rj-k-no


User avatar
Horst Sergio
Frequent Poster
Posts: 406
Joined: Thu Oct 29, 2015 10:57 pm
Kiting since: 1999
Favorite Beaches: Every puddle I can find in Central Europe,
the unpopular the better
Style: SLOW STYLE & stuntkiting
Gear: Just MONOFOILS, no training wheels ;-)
OZONE chrono, FLYSURFER sonic²/r, CONCEPTAIR wave
Brand Affiliation: KITEJUNKIE.com 's prank monkey
Contact:

Re: Monofoil or "riding stabless", setup and riding

Postby Horst Sergio » Sat Sep 01, 2018 11:46 am

I would say basicly a canard,
but with massive extra drag and lower stability, so in sum similar to all the twin tip foils we have seen the last years and I fear it will have the same "success" :-?

Oh and I think a shorter chickenloop would be helpful for his back :wink:

User avatar
flying grandpa
Medium Poster
Posts: 140
Joined: Tue Mar 11, 2014 10:02 am
Kiting since: 2005
Local Beach: Siemiany, Rewa
Favorite Beaches: Stegna, Orle, Karwia
Style: hydrofoil long distance, slalom, waves
Gear: ZEEKO, Soul, Sonic.
Brand Affiliation: NONE
Location: Poland

Re: Monofoil or "riding stabless", setup and riding

Postby flying grandpa » Sat Sep 01, 2018 9:17 pm

After four learning monofoil sessions done with back XXL Spitfire foil and 13m Sonic 2, I tried to ride behind a motorboat. Didn’t expect it would be as easy. Start speed some 8-10 knots, max about 15. With higher speed the nose dives, not easy to prevent it. For me it looks reason is that COP cannot follow COG at lower AoA = higher speed.
Horst Sergio wrote:
Wed Aug 29, 2018 9:43 pm
But if the load point is 2 or 4 times the wing span above the wing, all those tricks could be worthless and only regulation as human brain can do the stabilisation job.

I wonder if camber increase would increase COP forward travel enough to keep up with COG forward move at higher speed - helping our brains to solve the problem.
I was trying Carver and XL front foils -less cambered (probably)- and found them really difficult, almost unrideble.
Sergio, what are your experiece with low cambered foils?
Below are 2 short clips from motorboat session:
phpBB [video]

phpBB [video]

What can I do to improve video quality? I loaded it to youtube directly from iphone.
Last edited by flying grandpa on Wed Sep 05, 2018 8:50 am, edited 1 time in total.

ronnie
Very Frequent Poster
Posts: 3804
Joined: Sun Jul 24, 2005 6:39 pm

Re: Monofoil or "riding stabless", setup and riding

Postby ronnie » Sun Sep 02, 2018 8:49 am

flying grandpa wrote:
Sat Sep 01, 2018 9:17 pm
After four learning monofoil sessions done with back XXL Spitfire foil and 13m Sonic 2, I tried to ride behind a motorboat. Didn’t expect it would be as easy. Start speed some 8-10 knots, max about 15. With higher speed the nose dives, not easy to prevent it. For me it looks reason is that COP cannot follow COG at lower AoA = higher speed.
The front XXL wing might work better? The front wing may have better anti-stall characteristics. A bit like the upper blue curve, or the lower yellow curve, in this lift/AOA graph?

https://sites.google.com/site/late631re ... rodynamics

User avatar
flying grandpa
Medium Poster
Posts: 140
Joined: Tue Mar 11, 2014 10:02 am
Kiting since: 2005
Local Beach: Siemiany, Rewa
Favorite Beaches: Stegna, Orle, Karwia
Style: hydrofoil long distance, slalom, waves
Gear: ZEEKO, Soul, Sonic.
Brand Affiliation: NONE
Location: Poland

Re: Monofoil or "riding stabless", setup and riding

Postby flying grandpa » Sun Sep 02, 2018 9:22 pm

Hi, ronnie.
In my first movie low motorboat speed was main reason of stall. The software is very interesting, but for our purpose it lacks wing momentum graph/calculations at varius speeds.
But front XXL wing may be a good idea, as it looks more cambered. I will try as soon enough wind will come.
Will post the resilts.

User avatar
flying grandpa
Medium Poster
Posts: 140
Joined: Tue Mar 11, 2014 10:02 am
Kiting since: 2005
Local Beach: Siemiany, Rewa
Favorite Beaches: Stegna, Orle, Karwia
Style: hydrofoil long distance, slalom, waves
Gear: ZEEKO, Soul, Sonic.
Brand Affiliation: NONE
Location: Poland

Re: Monofoil or "riding stabless", setup and riding

Postby flying grandpa » Wed Sep 05, 2018 6:42 am

Yesterday tried front XXL wing. A bit higher speed was needed and it become quite comfortable. Also max speed was higher making comfort speed bandwidth wider.
So, tried carver once again. Success. I liked this wing the most. Widest speed bandwidth.
So tried Zeeko carbon race wing.
Succes. Rideble.
Tried Zeeko speed wing. Failure.
Tried older wing from another french foil brand. Failure.
First thoughts are below:
- more wing surface helps
- careful hydrodynamic design to avoid waterflow instabilities is a must
- all above foils were not designed for monofoilig - there is more room for comfort for sure, especially to widen comfort speed bandwidth.

User avatar
Horst Sergio
Frequent Poster
Posts: 406
Joined: Thu Oct 29, 2015 10:57 pm
Kiting since: 1999
Favorite Beaches: Every puddle I can find in Central Europe,
the unpopular the better
Style: SLOW STYLE & stuntkiting
Gear: Just MONOFOILS, no training wheels ;-)
OZONE chrono, FLYSURFER sonic²/r, CONCEPTAIR wave
Brand Affiliation: KITEJUNKIE.com 's prank monkey
Contact:

Re: Monofoil or "riding stabless", setup and riding

Postby Horst Sergio » Wed Sep 05, 2018 8:30 am

Thank's for testing and all the shared Information :thumb:
flying grandpa wrote:
Wed Sep 05, 2018 6:42 am
- all above foils were not designed for monofoilig - there is more room for comfort for sure, especially to widen comfort speed bandwidth.
My words, this is the main reason why I started this topic: Let's try to collect Information about the needs for a well balanced monofoil and one day a shaper who is willing to put them into a monofoil only product. :thumb:
flying grandpa wrote:
Wed Sep 05, 2018 6:42 am
- more wing surface helps
- careful hydrodynamic design to avoid waterflow instabilities is a must
-Yes surface is a must for beginning to allow slow flying speeds. But since some days a ride a 550 mm² high AR 7 wing to understand its characteristics and it behaves pretty well maybe also due to low surface
- Yes it is also my impression that hydrodynamic design should have been set well all over:

Tried a simple flat Nobile wing as monofoil a while ago and was surprised by its high drag, while I still think flat wings could have some potential for even more gentle surfacing
Tried a high swept back wing out of fiberglass and it felt spongy and not to good

Most experience for me 63 kg with this three Levitaz wings all with pretty low chamber (Surface in mm² / Span in cm / Chord in cm / AR)

Cruizer (990 / 63 / 19 / 4,3)
Best beginner wing tested till now, due to highest surface, range till now 16-34 km/h but expandable. Needs a 96 cm strut otherwise wide span will breath in 360 and it is not so good in surfacing, maybe shorter strut in waves possible. Due to slow speeds great to learn manouvers and for flying landings (use actuall reinforced struts to stand the loads). Riding it long time at higher speeds can consume leg force as if pitching up force can be violant due to high surface. Greatest for ultra light wind.

Element (680 / 50 / 16 / 3,9)
Most used and still most liked and all purpose wing speed range 19-38 km/h but expandable. Not tested but for sure also able to use 85 strut due to low span and great surfacing characteristics (no catapults). Not the best in any disciplin but very good in most and so overall. Even with this low AR upwind angle (with freerace foilkites) up to 38° are possible.
Just one experience in waves but felt the great potential. Very nice save jumping and landing anyway (wing forward or flying).

Aspect (580 / 60 / 12 / 7,0)
Definetly no beginner wing but if you manage get it in flight at 21 km/h it also could be flown pretty high, till now just 35 km/h but high potential. Due to lower surface it feels less violant at higher speed, but back brain concentration is higher so don't think to ride it 2h 50 km wide as the Element. Behaviour for just 12 cm chord is realy "stable" and gentle but use it with a 110 cm strut which feels to be a need. Feels interesting due to even higher performance as up to 30° upwind and great for boosting. But on the end more experimental as main goal of monofoiling for me is no sharp tips and no 110 cm struts but a performant but save and compact all over design.

Hope to get a new wing today, lets see

@ronnie:
yes, hope to find somebody who can deal with also the Information in the diagramm to find the best monofoil profile


Return to “Hydrofoil”

Who is online

Users browsing this forum: Séb and 3 guests