Wednesday, September 17, 2008

A Lancair builder has collected a list of links to tech papers, e.g. NLF215F


Interesting technical papers

There is link to the NLF215F airfoil tech paper. It was particularly interesting. Now I understood the philosophy of the profile - I was always wondering, why this profile has the low drag bucket at so high Cl (around 0.5) rather than what is realized in cruise with small aircraft (up to 0.2). But, it seems, that this airfoil is designed to be used with -10 degrees flaps. With those, the low drag bucket gets into the cruise area. Heureka.

Here is a direct link to the paper:


N91CZ said...

You are correct. The use of negative flaps also greatly reduces the pitching moment of the section in cruise.
I've used the following two charts during presentations when discussing this concept relative to Lancair performance.

N91CZ said...

Unknown said...

Thanks for your comment. I will look at your links!