MaxSurf profile question

[ErikG]

When making a 0009 profile MaxSurf and comparing it to a published 0009 profile in "Theory of wing sections". There is a significant difference around the forward 20% of the profile...

The published profile is blunter and slightly thicker than Masurf's built in 0009 profile.

Why the difference? Andrew?

[Andrew Mason]

Erik

You appear to be correct, the section looks to be wrong. I have redone the fit using Maxsurf Pro's surface fitting code and this gives the following control point x and y positions -

-1000.0 0.0
-940.9 7.3
-800.5 20.9
-593.2 35.3
-370.2 46.7
-176.0 43.9
-79.3 34.5
-1.4 16.7
0.0 0.0

These co-ordinates are in millimeters and are using 9 control points and order 4 splines. I will ammend the 0009 template in the shipping version of Maxsurf to reflect the corrected control points

The fit for the leading part of the aerofoil looks like this, compressed 4:1 along the longitudinal axis -