Monday, September 8, 2008

NLF airfoil with low pitching moment

I have been searching the web for such airfoil, and it seems like there is no such thing in the public domain. At least I have not found one.

For a canard/tandem configured aircraft, the main wing should have very low pitching moment, preferably zero if possible. The flying wing airfoils generally don't have very extensive laminar flow and they are not that interesting except for some exceptions (found one Wortmann airfoil which has quite high L/D but does not really compare to the drag coefficient of the NLF414F at high reynolds number).

So what I would be looking for would be:
- a thick (16-20%) low reynolds number natural laminar airfoil which has low or zero pitching moment, has design cruise Cl of 0.1-0.2 and which would have comparable drag charasteristics than the NLF414F or not very much higher drag than the NLF414F and which would have design cruise reynolds number around 5 million (not 10 million like the 414F) and which would achieve unflapped Cl of 1.2...1.3 at reynolds number 0.8 million.

So am I looking for an impossible airfoil? If you know that someone has designed and tested in wind tunnel this kind of airfoil, please let me know!

2 comments:

Craig Catto said...

Hi Karoliina, I designed and built most of the Gold Class Formula 1 aircraft wings at the Reno Air Races. And used a modified NLF 414 airfoil on "Endevor". This airfoil was modified for low cd at higher cl's and also lower pitching moments. Mods were done by Harry Riblet here in the USA. He is an old school guy and has no email. However if you wish, I can give you his snail mail info.. Regards, Craig Catto

Unknown said...

Thanks for your comment. Very nice to hear from you! This NLF414 modification is very interesting and I would like to learn more about it. You can give me his snail mail if you want my address is format karoliina dot t dot salminen at gmail dot com. Thanks a lot in advance!