Author Topic: Fly the Wing - Take off the Stabilizer  (Read 12265 times)

Beasho

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Fly the Wing - Take off the Stabilizer
« on: August 16, 2018, 04:03:53 AM »
Could this be a game changer? 

There is some debate on the effectiveness of BIG vs. SMALL stabilizers.  I just took mine completely off.  And the rig still flew. 

A little pitchy BUT IT FLEW!

I even attempt a few pumps at the end.

PS: Remember I was a TOTAL BEGINNER ON THIS THING WITH NO TAIL

https://youtu.be/R1JtyCniz0s
« Last Edit: August 16, 2018, 04:43:09 AM by Beasho »

Beasho

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Re: Fly the Wing - Take off the Stabilizer
« Reply #1 on: August 16, 2018, 04:08:01 AM »
Stabilizers are most important at slow speeds and for STABLE FLIGHT.  This would apply when LEARNING.  This may also apply when starting, or (maybe) when slowing down in a turn.

Unlike anything artificial that flies we are using Weight-Shift Control.  Hang gliders are the exception and have no tail.  Birds use weight shift control and wing warping and have very little tail.  Every single modern airplane with a tail uses control services. 
 
Check out where my front foot had to be to fly ~ 8 inches behind the front strap.  This is a huge revelation because it shows how much DOWN FORCE the tail wing is producing.  My CG (center of gravity) has moved on average 4 inches backward to fly in a stable configuration.  More math and pictures to come.
  • Down Force = Drag
  • Down Force becomes overwhelming front foot pressure in big waves
  • Any potential benefit of Downforce may be unnecessary at high speeds or with better skill
  • The flying wing is the most efficient and maneuverable configuration
« Last Edit: August 16, 2018, 04:45:40 AM by Beasho »

Beasho

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Re: Fly the Wing - Take off the Stabilizer
« Reply #2 on: August 16, 2018, 04:20:07 AM »
At the very least we could afford to fly with smaller stabilizers and or eliminate the camber on the stabilizer e.g. make the stabilizer symmetric.

Here Tony Logosz discusses the influence of stabilizers.  His experience stems from Kites and Windsurfers.  There may be a need for a vertical stabilizer in those contexts that we surf foilers do not need (as much).

https://youtu.be/p4W7mfIgIkk?t=133

SUPeter

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Re: Fly the Wing - Take off the Stabilizer
« Reply #3 on: August 16, 2018, 04:27:13 AM »
Definitely a game changer.  Making something relatively hard to more hard.  I'm taking a different tack.  More stabilizer, with propulsive effects.  Do you see there being a negative to having a stabilizer?  I'm curious.

Beasho

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Re: Fly the Wing - Take off the Stabilizer
« Reply #4 on: August 16, 2018, 04:28:09 AM »
PS: For you home-built types this could be great news.  Buy a front wing that works and then get 80% of the trim control by building small rear wings out of balsa & carbon.

I have found that the IWA is the perfectly balanced wing size that lets me get in early, to avoid death in big waves, and then pump when you run out of energy down the line.  The problem is the overwhelming front foot pressure and the sense that you are about to blow out of the water. 

My spidy-sense tells me there is something here.

Beasho

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Re: Fly the Wing - Take off the Stabilizer
« Reply #5 on: August 16, 2018, 04:31:41 AM »
Definitely a game changer.  Making something relatively hard to more hard.  I'm taking a different tack.  More stabilizer, with propulsive effects.  Do you see there being a negative to having a stabilizer?  I'm curious.

Removing the stabilizer IMMEDIATELY turned my Longboard into a Shortboard. 

The 6' 6" Easy Foiler pumped quicker and with more responsiveness than my Ghetto foiler.  This tells me is that the stabilizer has a HUGE influence. 

And YES - You can go Bigger, Go Smaller, Remove the thing or add trim tabs that could be modified on the fly depending on conditions. 
« Last Edit: August 16, 2018, 04:44:25 AM by Beasho »

Beasho

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Re: Fly the Wing - Take off the Stabilizer
« Reply #6 on: August 16, 2018, 04:38:04 AM »
The GoFoil design has changed VERY LITTLE since Kai first flew on an ELONGATED DOWNWIND board. 

There was in incredible cantilevered weight in the form of 10 Feet of Nose.  Without the huge downforce on the tail he may never have flown. 

Since then the 'designers' just made bigger wings.  There was little attention paid to the physics of what was going on underwater (*This may not be true for all designs).  Empirically they worked in small to medium sized waves.  Anyone who has ever tried to take off on a steep 8 to 10 foot +++ face knows that the current configuration is compromised. 

The dream is to pump up onto a non-breaking 15+ foot face and then race down the line, away from the death zone, flying free.

Here is the video of Kai's progression. 

Are we be putting Race Car bodies on Cadillac chassis?

https://youtu.be/h7XupqFOFSg
« Last Edit: August 16, 2018, 05:20:16 AM by Beasho »

PonoBill

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Re: Fly the Wing - Take off the Stabilizer
« Reply #7 on: August 16, 2018, 06:13:21 AM »
There's a guy in Maui building a flying wing foil, and the original notion of the geezerfoil was flying wing. There are a lot of good reasons for taking that direction, mostly centered around pitch control and drag. It's much harder to alter pitch with a fuselage and stabilizer. That translates into stability at a specific speed range and slow response below the range, loss of control above it.

It's rare to see designers and manufacturers move far from original designs--it takes a powerful reason to do so. And the answer to your question is Yes, we put race car bodies on Cadillacs for a very long time.
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Fishman

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Re: Fly the Wing - Take off the Stabilizer
« Reply #8 on: August 16, 2018, 07:13:30 AM »
So interesting, I love the way you think.

 You say it pumped quicker, but does the pump still create propulsion?  I don't know but I thought the "pump" propulsion came from leveraging power between the front and rear wings. Maybe if the wing was a lot wider (front to back)

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norcom

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Re: Fly the Wing - Take off the Stabilizer
« Reply #9 on: August 16, 2018, 11:48:49 AM »
There's been a discussion on the kite form about "riding stabless" for a while: http://www.kiteforum.com/viewtopic.php?f=196&t=2393935&start=10 I've been wanting to try it with the kite and the SUP foil just to see what it would be like but still haven't got around to it.

blueplanetsurf

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Re: Fly the Wing - Take off the Stabilizer
« Reply #10 on: August 16, 2018, 02:04:25 PM »
Cool Beasho, interesting stuff.  I like using smaller tail wings even with bigger front wings but have never tried no tail wing.   
I have thought of mounting a long batten off the tail as a stabilizer, instead of using a tail wing.  It should flex for easy pumping but would also stabilize the pitch of the foil, thoughts?

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DavidJohn

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Re: Fly the Wing - Take off the Stabilizer
« Reply #11 on: August 16, 2018, 03:29:36 PM »
Maybe motorcyclist should take off their front wheels to..  8)

https://youtu.be/HT9f0bv3Eck

Just kidding.. I was looking at the big Naish XL foil yesterday and their stabilizer is HUGE.. Personally I want to make foiling easier not harder and the guys in the shop said the big stabilizer helps heaps for stability.

Fishman

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Re: Fly the Wing - Take off the Stabilizer
« Reply #12 on: August 16, 2018, 04:19:29 PM »
Maybe keep the horizontal stabilizer,, but allow it to pivot up and down 15-20 degrees or so. Changing the angle may reduce drag and increase the pump push. 

There a flex fin  back in the late 70s which was a soft polyurethane, skateboard wheel type of polyurethane with a solid core inside, that thing would feel like it pushed me out of a turns.
The horizontal stabilizer would be acting like a fishes tail fin.
« Last Edit: August 16, 2018, 04:24:30 PM by Fishman »
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Evan Lloyd

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Re: Fly the Wing - Take off the Stabilizer
« Reply #13 on: August 16, 2018, 04:45:56 PM »
Well, that didn't take long.  We are officially in the weeds.  Next, we will be playing with mast lengths, fuselage lengths, tri-wings, and quad wings.  Maybe the surface of the wing should have divots like a golfball for better aerodynamics.  I can barely surf the damn thing and you guys want to make it harder.  "Hey buddy, you're looking good on that bike, let's take off the back wheel and see how you do." 

Like I need it to be more challenging.   ;)

kiwi

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Re: Fly the Wing - Take off the Stabilizer
« Reply #14 on: August 16, 2018, 06:07:20 PM »
After talking to the designer of the axis foils it seems the only foils which actually require the prefect stab is kite foiling. Apparently it's essential when flying at 40 knots  ;D no surprise really. I think he mentioned something about windfoiling also need them for high speed flight but everything else just has them to make them easy to fly.

 


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