Here's the latest NACAAirfoilGenerator script with various minor and a few major improvements since first release:



RELEASE NOTES:
- Now generates all 'basic' NACA four-digit and five-digit series airfoils, including 43012A.
- Variable thickness trailing edge (T.E) implemented.
- Zero T.E. thickness airfoils now draw correctly.
- Conformity of output with official NACA ordinates has been verified* for NACA 0012, 6518, 23012, 43012 & 43012A, see file:
NACAAirfoilGenerator ordinates vs airfoils-2015-03-23.3dm in the attached zip.

* "verified" is probably not the best word, as errors are known to exist in the original NACA ordinate data. As you can see though, output from the script appears to be a reasonable match to the ordinates for the above mentioned airfoils at least:



KNOWN LIMITATIONS:
- Five-digit airfoils with reflex camber lines are not yet implemented.
CAUTION:
A4 coefficient (slider) value input can be set by user 'out of NACA limits'.
- Input parameter validation is rudimentary where it has been implemented.
- TODO: Implement four-digit modified, five-digit modified, and six-digit series - http://m-selig.ae.illinois.edu/ads/naca980820.bas contains working (public domain) code likely worth incorporating.

Generating airfoils with less than 60 chord-wise stations is not recommended as the airfoil's curvature smoothness, when checked with a curvature analysis tool, reduces noticeable. Conversely, generating more than 100 stations doesn't appear to yield much if any noticeable improvement.

I'll make a post about how the thickness distribution curve for the 43012A was generated with an additional reverse-action script another day. That kept me pretty busy for quiet a while.

As ever, any feedback - especially bug reports - is always appreciated.

- Hamish