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Old Aug 03, 2006, 01:33 AM
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Buzz Bomb's Avatar
United States, GA, Stone Mountain
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Why does the Slow Stick fly so slow?

Hi all...

I'm currently designing a float plane for the lake in my backyard. The lake is really the only place I can fly a plane safely in my neighborhood. I'm doing all this so when I get withdrawl from not being able to fly because of family/fatherly responsibilities, I will have something I can fly right quick in my backyard. The Aero Ace that was taking up this role is getting boring.

I want the plane to have a lot of thrust but not a lot of speed. I have no problem doing that. What I want to know is what makes a plane like the GWS Slow Stick fly so slow?

Is it the wing design that does it? Or is it weight vs lift? Incidence of the wing, etc?
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Old Aug 03, 2006, 01:41 AM
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Fountain Valley, California
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It has a large wing, some call it a kite or parachute. It has a high AOA (angle of attack) that is; it is angled up compared to the stabilizer. It has a low wing loading (it's relatively light).

These qualities make the Slow Stick slow.

Now, boomerace, hell be along, hes made and flown more Slow Sticks than anyone. He can tell you everything youd ever want to know about Slow Sticks.

Will
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Old Aug 03, 2006, 02:25 AM
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Canberra, Australia (Southside)
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Large wing area + light weight = light wing loading -> slow flight

Thick section with undercamber = drag -> slow flight

I've seen a slow stick float plane around here somewhere called the 'float plane'. Enjoy!
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Old Aug 03, 2006, 02:34 AM
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I think I asked the question in the wrong way. I understand about high lift to weight, thrust vs speed, drag, etc. I was more concerned with the wing design than anything.

I've looked at pics of the slow stick and I see that it has some dihedral, but it is also swept back to some degree. What is that called? More importantly what does the sweeping back of the wings do?
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Old Aug 03, 2006, 02:44 AM
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Sweep (which is the right term BTW) increases the angle of attack of the stall... which helps control at slow speeds. You can go too far, though... past 30 degrees, you can get a 'deep stall', where after the stall the AoA wants to keep on increasing.

The thick airfoil is likely to make more lift at higher AoA as well. If you want a real slow flier, you need a high-lift airfoil.
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Old Aug 03, 2006, 02:48 AM
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Quote:
Originally Posted by Andrew McGregor
Sweep (which is the right term BTW) increases the angle of attack of the stall... which helps control at slow speeds. You can go too far, though... past 30 degrees, you can get a 'deep stall', where after the stall the AoA wants to keep on increasing.

The thick airfoil is likely to make more lift at higher AoA as well. If you want a real slow flier, you need a high-lift airfoil.

I'm not quite getting what you mean by AoA of the stall. Could you explain more about that?

Thanks
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Old Aug 03, 2006, 03:42 AM
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Ok, people usually talk about a stall speed... but really, the wing stalls at a particular angle of attack (that is, angle between the wing chord and the relative wind). That sets a speed because there's a speed at which the angle of attack you need to maintain level flight equals the stall angle of attack; you can't fly level any slower.

Landing speed in fullsize flying is 30% above the stall; with models you can't really tell, but you'd aim for about that, because any slower and the handling gets intolerably mushy. In any case, for a slow flier you clearly need a very slow stall. There are two ways to achieve that, and you can use both at once. One is low wing loading, and the other is to use a wing foil that stalls at a high angle of attack. Sweep helps by increasing the stall AoA even further. Flaps help by increasing it further again, and also creating drag so you can run more power at slow speeds (which helps with the mushiness, and allows prop wash to give you some more lift as well).
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Old Aug 03, 2006, 07:29 AM
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Greenville/Anderson area of SC
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Joe,

While you are designing your new "water taxi", try flying the Slow Stick flying boat: http://www.rcgroups.com/forums/showt...at#post5379931

I'm flying one off my pond.

Just what you are looking for.
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Old Aug 03, 2006, 07:41 AM
Next time I'll ARTF...
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Canberra, Australia (Southside)
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That's the one I was thinking of!

I think the 'sweep' that you speak of is washout (a sort of twist where the trailing edge kicks up a little at the rear). This is a feature of slow flying wings which aids stability / eliminates tip stalling. Not too much or you lose an angle of attack.

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Old Aug 03, 2006, 10:14 AM
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United States, GA, Stone Mountain
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Quote:
Originally Posted by Solid Hit
Joe,

While you are designing your new "water taxi", try flying the Slow Stick flying boat: http://www.rcgroups.com/forums/showt...at#post5379931

I'm flying one off my pond.

Just what you are looking for.
Thanks for the info. But I have already read that thread from front to back. I have stuff to use to make a home made one from old planes. I was trying to avoid buying new equipment (ESC, motor, servos, etc). Especially for something like this.
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Old Aug 03, 2006, 01:20 PM
turn, turn, turn.
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Last edited by kkens4; Aug 03, 2006 at 05:40 PM.
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Old Aug 03, 2006, 03:54 PM
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Suckiness is in the mind of the belittler. Slow Sticks are fun.
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Old Aug 03, 2006, 03:57 PM
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First plane I could actually fly on my own. Still have it and fly it. Very relaxing and great for AP or drop box.

Will
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Old Aug 03, 2006, 05:07 PM
turn, turn, turn.
Athol, Massachusetts
Joined Oct 2005
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Quote:
Originally Posted by roidspop
Suckiness is in the mind of the belittler. Slow Sticks are fun.
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Last edited by kkens4; Aug 03, 2006 at 05:41 PM.
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Old Aug 03, 2006, 05:11 PM
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LOL! Having a bad day kkens4?
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