slope wing question

[omega blood]

What airfoil(s) and how much washout for a fast slope wing?

[Ollie]

A lot depends on what kind of wing planform you are talking about. For a fast, plank type wing, see:
http://www.bowmanshobbies.com/jw.html
For the coordinates you have to join the X-Foil group, see:
http://groups.yahoo.com/group/xfoil/files/JW%20Airfoils/

For a swept back flying wing, the S5010 is very good. It has been used on F3B and F5B flying wings in Germany.
Also the MH64. See:
http://www.mh-aerotools.de/airfoils/index.htm

For the design of swept back and tapered flying wings there is a spreadsheet to calculate the washout.
See:
http://www.b2streamlines.com/Panknin.html

For a sweptback flying wing, the washout depends on the zero lift angles of attack of the airfoils, the pitching moment coefficients of the airfoils, the amount of sweep back, the taper ratio, the aspect ratio, the CG location and the pitch trim conditions the the designer wants. There are no simple, pat answers to the question of how much washout. A change in any one of these factors will change the amount of washout. So, the answers vary all over the lot, from zero to over 10 degrees.

[omega blood]

Thanks olie. I'm planing on an epp wing for my buddy. somthing like a wing warrior or zagi clone.

[Ollie]

This site has verbal comments as well as technical data on a number flying wing airfoils. See:
http://www.aerodesign.de/english/profile/profile_s.htm
There is one in the group that is supposed to be an improvement on the Zagi airfoil.

If you are thinking about a Zagi type planform, one of the best things you can do is fill in the gap between the inside ends of the elevons with a bat tail addition. There is a lot of drag associated with the Zagi planform because of middle effect and a chopped off airfoil contour. This drag limits top speed severely as well as reducing light air performance. In otherwords, the trailing edge between the elevons should curve back to a point and be as thin as possible consistent with durability. For an example of this planform see the Horton IX at:
http://www.nurflugel.com/Nurflugel/Horten_Nurflugels/horten_nurflugels.html


Keeping all the radio gear and linkages inside for a bump free exterior will also improve speed. Think about RDS drives for the elevons.

[omega blood]

AHHHH the horton IX. If I could make it look like one I would. It's on my to do list and it's not for me.
Thanks for links olie.


P.S. BTW what does "nurflugel" mean?

[Ollie]

Nurflugel is German for "only wing."