design programs

[frank40]

I will like to design my own plane, this will bee my first :eek: . Dose anyone knows some programs to cal. CG and wing-profile design programs.

Thanks in advance.

[CloudyIFR]

XFLR5 I believe is one that may interest you.

Search via your favorite search engine.

Curtis
Montana
www.TailwindGliders.com

[Montag DP]

Some of the most useful programs for me:

Profili 2 (uses the XFoil engine for processing) (http://www.profili2.com/eng/default.htm)

TurboCAD Pro 14 3D modeling software (http://www.cadandgraphics.com/tcpro14.html) (it's not the latest version but it has almost all the same features for 1/10th the price).

For all the rest of the design calculations I just use "pencil and paper."

[frank40]

thanks for your help ;)

[eflightray]

Airfield Models site (http://www.airfieldmodels.com/) is a great source for information on designing, the maths involved, trimming and , well just about everything. Well worth a look.

[windywestflyer]

I'm building my own plane as well. The programs I'm using are called xfoil, profili, and octave. Octave is an engineering math program that is good for data processing and all around math. It's very powerful. You could use excel instead if you feel better with it. All of these programs are free.

The best advice though is to build it the best you can and guess if you have to. If it looks right it'll probably work.

[frank40]

Hello again

I have been building my first design, done some test flights and it is still in one pice. :D
But I do have some difficulty to fine the CG and the thrust angle. I use the program sailorplane Cal.
To fine the CG but I am not sure that it is correct to use this prog. For a delta design.

Again thanks for you help, I will keep trying tile I get it right.

[frank40]

Hello again

I was wondering if there is a way to calculate the reflex offset for delta wings. All my delta winged planes have to have 4-8mm off up reflex. And does anyone know why it is so.

Thanks in advance

[Montag DP]

Hello again

I have been building my first design, done some test flights and it is still in one pice. :D
But I do have some difficulty to fine the CG and the thrust angle. I use the program sailorplane Cal.
To fine the CG but I am not sure that it is correct to use this prog. For a delta design.

Again thanks for you help, I will keep trying tile I get it right.If you wait a month or two I should have a spreadsheet done to help find the CG of any plane. Basically you'll be able to build all the structures in separate pages and then it will tell you where the CG should be. You'll also be able to use it to experiment with component placement (like the battery, servos, etc) to see where to mount them to get the CG right.

Unfortunately it won't be done for awhile. But for now maybe just try a flying wing calculator. Draw the wing so it covers the area of the wing + fuselage of your design, and that should be plenty conservative.

[frank40]

Hi Montag DP

Sounds like just the program that I need, I will look forward to when it is done. I have found some info, that I understod so I think I am Ok for now.