Need a big glider airfoil
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Need a big glider airfoil
I plan on scratch building an EPP sailplane, 4.3 meter wingspan. So far I am thinking about using a sd7037 or s3021 airfoil, but Im not sure which is better suited to a plane of this size. I expect the final weight to be around 90 - 100 oz's. Could anyone suggest some preliminary wing parameters (chord, thickness, root). Also, the wing will be built as 2 pieces... where each half is composed of 2 panels. So, its possible to maybe use a different airfoil at the tip panel.
Mainly, I dont really know much about bigger planes, so any advice would help alot.
Thx in advance
Mainly, I dont really know much about bigger planes, so any advice would help alot.
Thx in advance
#2
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RE: Need a big glider airfoil
I don't konw what kind of your sailplane?
It is a powered sail or no-power?
I plan make a electric sailplane, wingspan is 200 inchs.
root airfoil is RG15
http://www.nasg.com/afdb/afshow.phtm...dat&name1=RG15
tip airfoil is NACA23012
http://www.nasg.com/afdb/afshow.phtm...ame1=NACA23012
or NACA 8H12
weight/area about is 3kg/sqm
It is a powered sail or no-power?
I plan make a electric sailplane, wingspan is 200 inchs.
root airfoil is RG15
http://www.nasg.com/afdb/afshow.phtm...dat&name1=RG15
tip airfoil is NACA23012
http://www.nasg.com/afdb/afshow.phtm...ame1=NACA23012
or NACA 8H12
weight/area about is 3kg/sqm
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RE: Need a big glider airfoil
EPP doesn't have a lot of it's own strength. To help things along without needing to get into complex spar systems that sort of defeats the simplicity of the EPP concept I would suggest a thicker airfoil at least for the center panes. Something like a Selig 4233 at 12% would be a good choice.
Actually any sailplane of this sort of span is going to require a complex and well designed spar system. The span alone means you're going to put a big load on the wing in higher G loaded turns and pullups. And if you want to make it a fairly high aspect ratio so it sort of looks scale like then you'll need a rigid skin on the wing to support it from torsional twisting as well.
At this size it's not a Cut N' Chuck project. Structural details to support the flight loads need to be carefully evaluated and planned for.
Actually any sailplane of this sort of span is going to require a complex and well designed spar system. The span alone means you're going to put a big load on the wing in higher G loaded turns and pullups. And if you want to make it a fairly high aspect ratio so it sort of looks scale like then you'll need a rigid skin on the wing to support it from torsional twisting as well.
At this size it's not a Cut N' Chuck project. Structural details to support the flight loads need to be carefully evaluated and planned for.
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RE: Need a big glider airfoil
Hi Mike.
Wingsection : you could use a HQW 2,5 12 or if you want a wing a little big thicker you might consider HQW 2,5 14. 2,5 stand for the chamberline and 12 and 14 for the thickness in relations to width of wing
I could suggest a rootcord f 300 mm and a tipcord of 200 mm.
These sections from mr. Helmuth Quabeck a very good and they respond admirably to flaps. Make these 22 % of wingcord.
and make the wing with 2 or ( better ) 3 flaps and ailerons in each wing.
Use a modern computerradio and have your pride and joy towed aloft by a competent pilot.
look into : www.gliders.dk
www.f3j.dk
www.iggnorge.com
www.igg-sverige.se
Kind regards,
hld - OY - 9901
Wingsection : you could use a HQW 2,5 12 or if you want a wing a little big thicker you might consider HQW 2,5 14. 2,5 stand for the chamberline and 12 and 14 for the thickness in relations to width of wing
I could suggest a rootcord f 300 mm and a tipcord of 200 mm.
These sections from mr. Helmuth Quabeck a very good and they respond admirably to flaps. Make these 22 % of wingcord.
and make the wing with 2 or ( better ) 3 flaps and ailerons in each wing.
Use a modern computerradio and have your pride and joy towed aloft by a competent pilot.
look into : www.gliders.dk
www.f3j.dk
www.iggnorge.com
www.igg-sverige.se
Kind regards,
hld - OY - 9901