Hello,I am planning to build a flying wing.I am almost done with my hot wire cutter so I can cut my own wings out of foam :)But I just do not know which airfoil.The plane needs to glide well, have got some weight on board, it will have about a 100mm wing span which is about 40 inch.Maybe this will be my first fpv plane so if it can fly for a little time that should be great.What kind of wing I a not shore of. I think I am going for the normal wing so wings to the back. But I can also do the wings to the front, but for what should that be better? Does is have more control or does it turns better?I have found 2 airfoils the sd 7003 and the sj-5. Should that be somthing?
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Are you planning on putting any washout on the wings at all? if not you will want to use a reflexed airfoil like any of the Eppler 300 series on this page here.
The hard part is figuring out the trim you'll need which is based on your planform and your CG configuration; here's a design strategy I recommend: Make a modified Eppler airfoil such that the elevon on the trailing edge is constructed of 3/16" foamcore board or a similar flat material. This way you can try out several different elevon shapes with whatever airfoil you cut on your wire cutter to find the right trim; it will be impossible to do so otherwise, unless you are modeling the plane in something like XFLR-5 or X-Plane's 'Planemaker' first before the physical build. The pictures below illustrate what I mean, I took the Eppler 332 and cut off the trailing edge, replacing it with a piece of foamcore board (shown in blue) and after that I added washout, that is, I lowered the angle of incidence of the airfoil at the wingtip relative to the airfoil at the wing root. Note that all the geometry shown here is very exaggerated and not to any scale; normally you wouldn't be able to see any pronounced washout at the wingtips as washout wouldn't normally exceed six degrees or so. Also, note the elevon is thicker at the wing tip than at the wing root; if you need me to explain this let me know, but suffice to say this should be the case if the wing tip is located more aftward than the wing root relative to the CG.
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Hey Edward,
Are you planning on putting any washout on the wings at all? if not you will want to use a reflexed airfoil like any of the Eppler 300 series on this page here.
The hard part is figuring out the trim you'll need which is based on your planform and your CG configuration; here's a design strategy I recommend: Make a modified Eppler airfoil such that the elevon on the trailing edge is constructed of 3/16" foamcore board or a similar flat material. This way you can try out several different elevon shapes with whatever airfoil you cut on your wire cutter to find the right trim; it will be impossible to do so otherwise, unless you are modeling the plane in something like XFLR-5 or X-Plane's 'Planemaker' first before the physical build. The pictures below illustrate what I mean, I took the Eppler 332 and cut off the trailing edge, replacing it with a piece of foamcore board (shown in blue) and after that I added washout, that is, I lowered the angle of incidence of the airfoil at the wingtip relative to the airfoil at the wing root. Note that all the geometry shown here is very exaggerated and not to any scale; normally you wouldn't be able to see any pronounced washout at the wingtips as washout wouldn't normally exceed six degrees or so. Also, note the elevon is thicker at the wing tip than at the wing root; if you need me to explain this let me know, but suffice to say this should be the case if the wing tip is located more aftward than the wing root relative to the CG.
I hope this helps.
Try the MH series, e.g MH 45, MH 60 etc.
MH45
MH60 10%
ritz
PW51