## Friday, May 5, 2017

### Aery Model Design Software Program

Someone on my Simple Foam Free Flight Airplane group on Facebook group posted a link to a program you can download to design simple model gliders, known as the Aery Model Design Software Program. Although this program was created a long time ago, for computer technology I was able to install the program fine on a Windows 7 computer. The program lets you adjust proportions for a glider on the screen and then outputs a bunch of data along with a statement if the glider should fly or not.

 Should Fly but not Efficient Design

 Moment Arms and Tail too Small

Part of what I see the educational value of this is to demonstrate how changing different design parameters in a computer program can quickly recalculate what the results should be for the design drawing. Parameters could be lengths and widths of flying surfaces, tapering the flying surfaces, using different weights of wood,   or moment arms and balance.  It quickly became apparent to me that to understand at all what the program was calculating you needed some background in aerodynamics.

 Nose weight added to shorten nose moment

 From my program to help explain Moment Arm

 Further Moment Arm Explanation

The program was a project by Alan Scott Estenson as part of requirements for Master in Science at University of Minnesota Graduate School. I found Mr. Estenson on Facebook and attempted to contact him but received no response. The program was tested with some student groups in Minnesota which is mentioned in the documentation which can be found at this link: http://www3.eng.cam.ac.uk/outreach/Project-resources/Senior-glider/Aery-technical-paper.pdf

I worked with designing a sample glider and trying to make it more efficient. Gliders per the program are made from sheet balsa and fuselage of spruce, the wing is a flat-plate airfoil. My intention is to build some sample gliders using the program and report my results in future blog posts. In my gliders I will add dihedral for stability, something the author did not include to make the construction simpler.

 Taper the Wing Trailing Edge

The webpage I created http://ideas-inspire.com/basic-aerodynamics-with-lesson/ Basic Aerodynamics with Lesson should be of some help in understanding the Aery program but more research is needed also.  I am including some glider outlines I created with annotations on some of the factors in the design, mainly related to proper balance and drag reduction in the tail surfaces.

Bill Kuhl