dehedral vs polyhedral.what should i use and how much.

[Percy Jakson]

 :help:i want to know whether i should use dehedral or polyhedral for my first plane ? the wingspan would be of 45 inch and the chord length is 9 inch. i would use a clark y airfoil and it is a trainer with fueselage would be below the wing.i wan't to know should i use dehedral or polyhedral? i want stability since there won't be ailerons.if adding  ailerons would make it more stable and efficient i would add it since i have got two extra servos  .if i should use dehedral what should be the angle and if i should use polyhedral what should be the angle as well as the length of it.i can even give you the whole plan for the plane.i would wan't my plane to be efficient and stable.it would be very grateful to all the experienced pilots who help me.

[K K Iyer]

@percy jakson,
Hi,
If this is your first build, and your first attempt at flying RC, with all due respect, do not start with an own design.
After all if you needed to learn cycling, you wouldn't try to design and build a bicycle yourself first!

You have three options
1. Get an ARF powered glider like Easystar, Skysurfer etc. Probably most painless way to learn to fly
2. Get a kit with all matching parts and accessories like from Vortex-rc
3. If you must scratch build, look at something like Blu Baby. Plans and comments aplenty on the net. Hundreds of other suitable trainer plans too. Eg, Flite Test

If you don't like these options, and wish to proceed with your own design, then use dihedral of 6-11 degrees each side. Depends on many variables, but a ballpark figure to start with.
Simpler than polyhedral and no need for ailerons.
You have probably already researched wing loading, power loading, stab and fin sizing, decalage etc., besides dihedral...

Best wishes and welcome to the forum.
Regards

Edit:
If you indicate the equipment you already have (tx, rx, motor, esc, prop, servos, lipos) and the material you plan to use (balsa, coro, depron, thermocol), you may get specific suggestions from members.

[prabal276]

My suggestion will be to go with the FT old Fogey as your first RC plane if you have depron/foam board/corroplast.
It dosent require any experience and the electronics can be reused in many other FT designs such as the simple cub and the simple storch.
I think you should delay the resigning of your own plane, if possible because you can concentrate more on the building and flying part as someone has already done the testing and research for you.
Regards