Help on wing design
 

Time ago, I´ve posted some questions about this particular wing. It´s a obscure Argentinian bomber called AeMB2 Bombi. Lack of 3 views doesn´t help...but finally I´ve it!.
I´m planning to build over 3 views, without plans. But wing at root has an airfoil very thick. It´s at 22 or 23 %. I´ve used profili2 to make a NACA 4423, and seems to be very close to taht of real thing.
But at wing tips my plans are to use NACA1408. ¿Why? just for enhance scale appeareance.
Model may be 1/8 scale EG 85 inch wingspan with a Saito 80 on its nose. I want it to fly like a bomber not as a P51!
I doesn´t want to have a spin stable plane capale of fly very well at low speeds, WITHOUT TO TIP SPIN !
Is this mix between NACA 4423 & 1408 SAFE ?
Look at my website for more details please:
http://www.geocities.com/bacosistemas01/AeMB2.html

RE: Help on wing design
 

I would say that's a very dangerous combination. You have a wing that is tapered approximately 50% and your tip airfoil will definitely not have the same maximum lift as the 44xx series, which will invite stalling at the tip. From this picture,

http://www.ipmschile.cl/imagenes/Art.../Bombi%203.jpg

The root airfoil looks more like a 23xxx series. You could then use the 44xx series at the tip with reduced thickness. Full size airplanes like the B-25, T-6 and P-38 use a similar progression.

RE: Help on wing design
 

WS
Thanks for your answer. Let me said that chilean IPMS model was build using info from my website, and it isn´t very accurate...At this moment I´ve lots of new information, but I can´t publish yet
Look at
http://www.geocities.com/bacosistemas01/Imagenes_1.html
There are lots of photos about the real thing.
Thanks again