Star Test - Compufoil Professional

by Michael Shellim c. 1998

CompuFoil Professional is a fully featured plotting package which runs under Windows 3.x, 95 or NT. The system is modular; extra features being added and paid for as required.

Feature List

• Full sets of ribs in straight taper, elliptical, or modified elliptical planforms
• Templates for foam wings.
• Sheeting compensation
• Wire kerf compensation
• Leading edges
• V-notches
• Building jig holes
• Spar slots

Impressions

Demo version v1.05A was installed on Pentium 120 PC running Windows '95. Tests consisted of

1. Generating some simple template plots
2. Generate compete "lofted" set of ribs for an elliptical planform.

A great deal of effort has obviously gone into the package. Some examples:

• Fractions can be entered as fractions rather than decimals, so if you're using to 1/16" sheet you can type in the sheet thickness as 1/16.
• Spars are generated parallel to the airfoil surface, exactly as you would draw them.
• You can generate a truncated elliptical wing (a true ellipse would have zero tip chord).
• The system allows the generation of general closed shapes such as circles and ellipses e.g. for bulkheads.

In Use

There is a myriad of options available in the program, but this flexibility comes at the expense of usability. For example, there are five different object types which are used by the program, each of which has a corresponding file type. I spent quite a while trying to figure out the relationships between .COR, TPL, LFT, USR and INV files and I haven't fully worked out how they are related.

Rib generation is very fast. A "join the dots" approach is used to generate a section rather than a more complex curve-fitting algorithm, but the difference is almost undetectable in the finished outputwith the airfoil co-ordinates supplied.

The help system is comprehensive. The help interface is unusual, consisting of two windows, one of which acts as a Table of Contents.

Some of the more advanced features such as the full screen airfoil editor are difficult to use "out of the box". If you are one of those who likes tinkering, you'll love this software!

See Screen Shot (18KB).

Note: since first publishing this review, I received some words of clarification from author Eric Sanders

[...] I want to give you a clarification of the file types first of all. .COR, .INV, and .USR are all simple text files of the coordinates. They are exactly the same. The different extensions are there for the user to help organize their files (.cor-standard coordinate files, .usr-user modified files, .inv-inverted airfoil files). The .TPL is a template file which saves all template information, the .LFT is a lofted file which saves all template informaiton as well as the wing information (panel length, rib spacing, root and tip airfoil type, chord lengths, etc).

Thanks Eric!

Availability

CompuFoil Pro has a modular architecture. All the functionality is built in to the package but extra features have to be unlocked before they can be accessed. This is done by purchasing a code number from the author and entering it into the system.

All prices as of 14 May 1995 - check before ordering.

Base CompuFoil program $35.00

Allows for printing of single foam or rib templates. This includes sheeting and wire kerf compensation, full foam template structure (ramps, washoutable base angle), leading edges, leading edge v-notch. The items listed below are not available in non-demo form in this simple configuration.

 

Modification Module: $12.00

The Full Screen editor - CompuFoil's built in co-ordinate editor.

 

Generate Module: $15.00

Loft full sets of ribs, an individual rib or foam template, or a three part set consisting of a root and tip foam template and a subrib for your joiner rod carrier. These can be lofted in a straight taper, elliptical, or modified elliptical planform. CompuFoil will also calculate the surface area, projected area, volumes, and automatically handle tip washout as well. Washout will automatically set the foam template base angle or jig hole angles in the case full set of rib loftings.

 

Jig Holes/Spar Slots: $10.00

Define template reference holes e.g. for either building jigs, or alignment rod/joiner tube placement. Compensates for washout.Spar slots allow you to position full depth spars, or stringer notches on your template in six different manners. If you're lofting ribs, CompuFoil can also automatically place tapered spars as well (both in thickness and width!).

 

DXF output: $10.00

N.A.C.A. Generator: $18.00 - Airfoil generator can produce four, five or six digit N.A.C.A. airfoils.

 

Airfoil library $13.00

240 airfoils to choose from. These include sailplane, power, slope, free flight, and flying wing type.

Contact:

You can download a demo or from Eric Sanders' web site at http://www.compufoil.com.

Pro's and Cons

If you want a high-end package which will cope with any requirement, look no further - but be prepared for a learning curve if you want to use all the features.

PRO'S

• Full featured, flexible package - fully justifies "professional" tag.
• Only pay for the functionality you need.

CONS

• Flexibility comes at expense of ease of use.

Merit Rating

• Features -
• Output Quality -
• Ease of use -
• Documentation - (on-line help)
• Robustness -