Slotted wing for propeller ?

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Vigilant1

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If we are talking about the ability of surfaces to act as a conventional rudder does--to push or pull the aircraft around the yaw axis using lift--then only their distance fore or aft of the CG matters. If we placed them on the wingtip exactly as far aft as the CG, their "push" or "pull" force arrow would point right through the CG and produce no rotation at all (just a displacement of the whole airplane to the left or right).
Now, if we are instead talking about causing yaw using drag (to pull on one wingtip or the other and thus rotate the aircraft around the yaw axis), then putting the drag surfaces out on a wingtip does provide leverage for that mode of operation. Do we want to yaw the airplane using differential drag?
 
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cluttonfred

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What he said plus a poor illustration…aerodynamic center, center of gravity, lever arm for impact of canted panels on directional control/stability. Compare that to the fin and rudder’s area and lever arm.

A71ECA2E-B410-41DC-BD75-135993FDE5D6.jpeg

If we are talking about the ability of surfaces to act as a conventional rudder does--to push or pull the aircraft around the yaw axis using lift--then only their distance fore or aft of the CG matters. If we placed them on the wingtip exactly as far aft as the CG, their "push" or "pull" force arrow would point right through the CG and produce no rotation at all (just a displacement of the whole airplane to the left or right).
Now, if we are instead talking about causing yaw using drag (to pull on one wingtip or the other and thus rotate the aircraft around the yaw axis), then putting the drag surfaces out on a wingtip does provide leverage for that mode of operation. Do we want to yaw the airplane using differential drag?
 
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WINGITIS

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I can see you just do not get it, a P-38 does not have them on the center-line, you also have the CG way to far back!

The AC lengthwise in relation to the CG is just for stability in side winds..

How do you think Planks and Flying Wings work.............
 

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WINGITIS

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They often use drag rudders/other drag devices to control yaw.
Often but not always!

Here is the ACTUAL AC from the diagram provided and with the tail removed, still behind the CG:

The CG cannot be where Cluttonfred put it because he has it on the back wheels.....

It would be somewhere between the Pilot/s and the engine, depending on where the fuel tanks are.

AC CENTER .pngAC WITH TAIL REMOVED.png
Winton-Facet-Opal.jpg
 
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Vigilant1

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Often but not always!

Here is the ACTUAL AC from the diagram provided and with the tail removed, still behind the CG:

The CG cannot be where Cluttonfred put it because he has it on the back wheels.....

It would be somewhere between the Pilot/s and the engine, depending on where the fuel tanks are.

View attachment 116194View attachment 116196
View attachment 116195
You can certainly try to design your own plane to work like that if you want. Regardless, it is very clear that the actual aircraft that was actually designer by Stark doesn't use the aileron surfaces as some type of forward V-tail. As you can see, he designed the plane with a generous conventional rudder, and that is how yaw control is accomplished.
If you want to use similarly placed surfaces to control both roll (by changing wing camber at the tips) and yaw (primarily through drag, though lift would work if they are far enough aft), you may need some sort of split surfaces to make it functional.
 
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WINGITIS

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You can certainly try to design your own plane to work like that if you want. Regardless, it is very clear that the actual aircraft that was actually designer by Stark doesn't use the aileron surfaces as some type of forward V-tail. As you can see, he designed the plane with a generous conventional rudder, and that is how yaw control is accomplished.
If you want to use similarly placed surfaces to control both roll (by changing wing camber at the tips) and yaw (primarily through drag, though lift would work if they are far enough aft), you may need some sort of split surfaces to make it work.
My initial statement was that I wondered if he had tried them as Ruddervators with the tail controls locked.

Maybe he did, he certainly would have gained an appreciation of how they affected the aircraft as NON CONVENTIONAL ailerons, but I dont think that has been recorded/documented anywhere.
 

Tiger Tim

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It’s all moot: if those could be used as rudders think about which way they would have to move to yaw the plane one way. Now think about how they’d have to move to roll the airplane the same way.
 
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