Mean aerodynamic chord for complex wing shapes - RC Groups
Feb 25, 2013, 05:50 PM
person
Discussion

# Mean aerodynamic chord for complex wing shapes

Gents,

I'm trying to figure out the MAC for a wing that's comprised of a straight section in the middle with two swept sections on either side. It's constant chord, so relatively simple. I'm just wondering if there's a way I can take the dimensions of the different wing sections (which are known) and compute the location of the MAC to determine where to put the CG?

Regards,

-DE
 Feb 25, 2013, 07:40 PM Registered User You can simply do a weighted average of the MAC for each single panel
 Feb 25, 2013, 09:10 PM Registered User Why don't you use the multi-panel CG calculator: http://wingcgcalc.bruder.com.br It's called a flying wing calculator but all it does is find the MAC and draw the CG based on the % you enter. So it's really a generic CG calculator. Once you've generated your configuration you can ask it to generate a link to your configuration that you can post elsewhere. Here's an example of a wing with straight center section and swept tips: http://j.mp/ZwoJuf
 Feb 25, 2013, 09:40 PM Red Merle ALES VI If you have a spreadsheet program Sailplane Calc may be of interest to you. It will do what you ask for a four panel wing. There is also an article I wrote which explains its use. Go to the Articles/Files page at www.TailwindGliders.com Curtis
 Feb 25, 2013, 09:56 PM Cognitive dissonance Or you can use Dan's nice CG calculator spreadsheet that can do up to 9 panels on each wing half, and do a good analysis of the tail and fuse contributions as well: www.rcgroups.com/forums/showthread.php?t=1106300 Kevin
 Feb 26, 2013, 12:57 AM person Sweet, thanks guys!
Jan 25, 2015, 03:18 PM
Registered User

# MAC form planform

Hi,

Here is the software that compute the position and length of the mean aerodynamic chord form a b&w picture of the planform of the wing (or airplane).
This is helpful in case of complex shape like elliptic wings.
You will find the executable, a short guide and some sample planforms.

Best regards

Philippe