yet another scratch-built trainer

Nice to see some original aircraft. I hope you have a video cam so we can see it with the electronics installed, flying around Mauritious.
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Have some advice for you, if you would take it.
First, your diherdar is waay to much its gonna wobble and dutch roll on turn, you might read the 30 degrees somewhere but that is not for one wing but for the two together, if one is sitting flush, that means 15 degrees per wing, wich is still quite much, but should be ok.

Second, the tailfeathers or rather the complete tail end, sorry to say this but you should loose it completely, these patched on contol surfaces with a quite disproportionate tail smells disaster for me.
Check this article it is mighty useful http://flitetest.com/articles/Design_Parameters_for_Scratch_Built_Airframes

I would urge you to design conventional looking tail feathers from a thin material, with correct proportions to your wing, also check the lenght of the tail.
Elevont mixing wont do you much good because there isnt a long enough level on the horizontal stabilizer to actually force the plane with such a large wingspan to turn, especially with dihedral as it will naturally oppose the turning movement. 3 channel control is good with dihedral and it is easier on the beginner pilot as well, just wire the rudder to the aileron channel.

One more very important thing, as you will have no idea where the CG is located, when ready and everything is installed, set your cg location to 30% of the wing chord, make it balance there (a touch nose heavy might do you some good) than do glide tests, just toss the plane and look how it sails if it pitches up than move the cg forward, if it dives to the ground quickly than move the cg back. Important thing, that you should do this with the battery and everything installed first!

Dont take this the wrong way, I dont want to tell you how to do things, just some friendly advice. There are some golden rules in aviation that should be followed and it is very hard to grasp all of them on a scratchbuild airplane especially if you are new to this field.
My experience is either the pilot or the plane should be very solid to have a good time when flying, so if you are just starting this hobby I would advise you to opt for some well tried out desing that wont give you any surprises, there are a bunch of these here at FT.
Designing your own plane is a good challenge but should be started after you are familiar with the rules of flight and have enough flying time under your belt that you can handle a misbehaving plane! Belive me, I learned it the hard way!


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That's a lot of dihedral. And a lot of air is going to spill right off the wing tips and give you very little lift.
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basically as Exhodus and others said, you will need less dihedral, a tail made of thinner material (and probably with a classic rudder and elevator design. no need for the elevons, rudder elevator and throttle will be plenty for your first flight, and elevons on the tail wont really work too well anyway). another thing you will need is overhang in front of the wing, this is necessary to get the CG in the correct place. you do not want to fly a tail heavy plane. also, for that heavy and powerful electronics, I recommend a 40-60 inch wing span to get nice flying characteristics.

brave to try designing your first airframe. the first one I built that flew was my own design, it can be done, just remember to glide test, always glide test.
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