Flying wing as cheap and simple option for basic fun flying.

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Sockmonkey

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Bear in mind I'm still not sure if adding junkers flaps to a plank means you can do away with reflex on the main wing. I think you either need to keep the reflexed trailing edge, or give the flap an inverted lift profile. Otherwise you would likely need to pull back on the stick constantly.
 

Hot Wings

Grumpy Cynic
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not sure if adding junkers flaps to a plank means you can do away with reflex on the main wing.
You can do away with the reflex. The Mitchell B-10 uses the 23 series foil with Junkers elevons that have a symmetrical profile. It is rigged to be at a 1 deg. negative pitch with the stick full forward. Trim tabs and/or spring trim could be used to provide neutral stick pressure at the desired trim speed. The U-2 used an inverted airfoil and twist on the Junkers. Didn't work out exactly as planned........
 

cluttonfred

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Yes, you can do away with the reflex, but should you? Up elevon on a plank is good for ensuring roll control at low speeds by effectively washing out the tips, but do you want to be getting all of your balancing force from the tips even in level flight? I don’t know the answer and don’t have the math skills to figure it out but intuitively that seems more draggy than a little reflex over the whole wing.

You can do away with the reflex.
 

jedi

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Bear in mind I'm still not sure if adding junkers flaps to a plank means you can do away with reflex on the main wing. I think you either need to keep the reflexed trailing edge, or give the flap an inverted lift profile. Otherwise you would likely need to pull back on the stick constantly.
Like with an up spring!

A down weight and up spring makes a stable aircraft. Great in turbulence.
 
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