Best airfoil for an 18" flying wing?

[TheDudeVT]

I'm looking for advice on constructing a small 18" flying wing- Something I can throw in a backpack and take with me to the top of a mountain. Can anyone give me tips on airfoil selection, wing sweep and washout? I currently have a some light weight gear including 3S1P 340 LiPos, a brushless CD-ROM motor, Pheonix 10 controller and 2 CS4.4 servos.

I'd like to optimize the airfoil for speed, so probably a thin airfoil with some reflex?

I would appreciate any ideas you might have-

Kyle

[vintage1]

Its going to be really fast at 18", so I would be inclined to fake up a wing from soft 1/4" balsa sheet more or less sanded to an airfoil section. And reflex the elevons. Any more compleity than that is likley to be a waste of time.

[DaveGherardini]

since your planning on flying it high i would optmize the foil shape for lift. it will be plenty fast in a dive. its going to be nimble because of size and if windy it will be tossed around easily. there are 100's of potential shapes. But ide pic a very high lift shape for agl above 5k. But since your asking for a particular thin reflexed shape an E636 would be a fair comprimise..

[TheDudeVT]

Thanks, I'll give the e636 a try- I just got my foam cutter rig operational, so now I can try a few different airfoils.

Vintage1- I agree about making it simple, but part of the fun is making wings on my new home-made hands off foam cutter, which I neglected to mention.

Kyle

[BMatthews]

In that case may I suggest the HS2.0/8.0? Thin, not much camber and reflexed for plank style wings. Should be FAST.