flying wing c of g

[mscj]

Here's the specs--6.75 root cord, 4.75 tip cord, 8.25 sweep, 40 in span, rtf weight somewhere between 16-17 oz....I've used a program called cmEi that figures mac and cg point--my question is, where should the cg be on a flying wing? I think 10-20% is right, but I'm looking for professional opinions! My calcs put it from 4.5-5.0 inches from the nose. Close, not so close, anyone? Thanks for the help, Mike.

[Sparky Paul]

12 to 15 percent of the m.a.c. should be OK. Move aft after flying, if you want more activity.
.
Sparky Paul
http://www.angelfire.com/indie/aerostuff
PJB's Seriously Aeronautical Stuff
http://home.earthlink.net/~pjburke1/aindex.html

[MikeC]

On my wings I have used "just forward" of the 25% MAC. I start 1/4" in front of the 25% mark for my first flights and adjust from there. My wings have all been sailplanes though, no motors.

Mike

[Gus Morfis]

Hi! It sounds like you are in the right ball park. I usually balance my wings at about 10% of the MAC to start with. This will make it doggy, to be sure. But then after test flying, in order to sort out your control throws and your trims, gradually shift your CG aft, until you are comfortable with your model....Cheers...........Gus

[mscj]

Thanks for the help, guys! Test flight today or tomorrow, weather permitting.