Glider basic questions of AOA and airfloil selection
 

Hi All,

A few questions concerning a EPP foamy glider I want to cut using my new foam cutter. It will be loosely modeled after an ASK18, I like the planform shape!

It seems the SD7037 foil is pretty common and since it is well proven in glider applications I will use it. I'm thinking a 72" ws with a root chord of 9" and 6" tip. The data for this foil indicates max lift/drag at 2-4 degrees positive AOA depending on reynolds number. Looking at the scale 3 view, the full scale AOA is a bunch. I will guess about 8 degrees positive. Did the full scale plane fly with a tail high attitude due to the AOA? How does 2 degees sound for my small model.

The full scale plane distance from trailing edge to horizontal stab is short, and I'm concerned that it might need a little more moment arm to keep it stable. Any rules of thumb on distance and stab/rudder size?

I am planing on using straight wing halves with dihedral and ailerons. Rules of thumb for the dihedral for a 72" span?

Thanks in advance for any advice,
Mitch