Airplane doesnt turn!

[Itflys]

Hello all, take a look at these two foam profile planes ive been playing with. They are blucore and and balsa from a 3 veiw drawings of the AT 6 Texan. The yellow plane flys good it has an slightly undercamberd wing with a small amount of dihedral. No moving rudder. The ailerons are added to the wing outline. Wing span is 34" and weighs 14 OZ. With the silver plane i wanted to get a little more agressive it has the exact dimensions as the yellow plane except that it has a midwing, flatplate airfoil with almost 0 dihedral the ailerons are the same size as the yellow plane only they are cut into the wing. The throws on the ailerons are the same on both airplanes. The elevator on the silver plane has been moved forward a little to give more clearance for greater rudder throw. These two airplanes have the same weight they both uses the same engine, the norvel .061. The problem now is with the silver plane in that it won't turn. On hand launch the plane climbs out nice but when i try to roll the plane it begins to roll into the turn but then it gets out of control it tries to pitch up and gets all wacky. Im thinking that it is adverse yaw but im not sure. This is the first plane ive built using a flat plate airfoil, does this have anything to do with it? I tried to turn with the rudder and ailerons but this thing gets so wild ive had to bail out on 3 or 4 flights without damage to the plane. Will differential ailerons fix this? Any input would be great. Thanks John H

[sq8s]

You need to move your CG back some. Mabe just bolt a lighter muffler on. you will notice great improvment in handeling.

[Itflys]

Thanks for the reply the CG is in the same location as the yellow plane which flys and turns great i can give it a try any more suggestions out there.

[Mike Taylor]

When you crank in up elevator to initiate the turn, and "then it gets out of control it tries to pitch up and gets all wacky", you may be stalling the flat plate wing. Move the CG forward a bit and/or reduce the elevator throw to see if that helps.

[Sparky Paul]

Sounds like adverse yaw more than anything else.
Try no down aileron at all.
100% differential.
The down aileron is pulling the nose up when you roll.

[vintage1]

I'll go with Mikes theory. Move CG forward - thats needed with shorter wing-to tailplane distance.

Blob of lead on the mufller, and give it a try.

[Itflys]

Thanks for the input guys, Ill report back as soon as i get another good flying day. How about a little rudder to aileron mix to help initiate the turn, this plane does have a short tail moment.

[vintage1]

My thinking is that if it rolls, but up elevator doesn't then pull it ino a turn, its because its naturally nose up already, and you need some more rudder area or more forwad CG to get it down.

So rudeer might help, you can try that on te sticks anwway to see.