hallo,guyz:

I wanna scratch build my first flying wing.
but i don't know how to build the twist or so-called washout?
and if i use different airfoil for the root and tip,then how to build such a wing?whether if i need to build a wing jig first?

thank you for your comment!
Dan

If it’s foam you need to make hot wire templates for the root and tip airfoil section then attach them to the foam at the angles that you calculate with something like the Panknin twist spreadsheet . If you want to work in balsa then you will have to draw each rib and calculate the angle of attack for each rib. Back in the stone age we used to do it all with pencils and a calculator, it took days. Now a program like CompuFoil can do all the work for you in less time than it takes to pick the airfoils you want to use from the menu.

--Norm

I'd certainly be interested in the thought process behind your design once you get there and technical info such as airfoil choices, wing sweep, wing twist, taper ratios etc....

I've just finished a very nice MS Excel spreadsheet for Dr. Panknin's twist spreadsheet. There are others out there but mine is accurate and also has a tutorial on how to obtain the airfoil data.

I've yet to post it on my website as I don't know what to use for Zero Lift Angle or Cmo of the airfoils, it'll be part of the tutorial. It's either Viscous or Non-viscous but as I write this I'm not sure exactly what Dr Panknin was looking for, it affects the data quite a bit, obviously.

Curtis
Montana

Thanks above
I am about to build a full balsa flying wing ,and I just want to design my own flying wing,the design method which i am using now got from the b2streamline,a arcticle titled"step by step design procedure for flying wing r/c model aircraft without any vertical stablisation aid".
and thank u for your pankin's sheet .
to cloudyifr: it seems your site is not available right now.
Dan

http://h1.ripway.com/cloudyifr/index.html

They must have been doing some maintenance as it's rare to go down, I use the website for my job on a daily basis too. I checked and bandwidth wasn't exceeded, try again and you should be able to get in.

Do you have a link to the article?

Thanks
Curtis

when you decide on you foils and such the washout is simple to build into a balsa wing just prop the triling edge stoch up b the amount of twist or tip reflex you want and build away I assume you will be building on a flat surface so the roo will be built flat and the tip le will be built on the same plane as the root but the tip will be twisted..

same as when building a glider wing with a bit of wash out in it..

you can make the ribs using the sandwich method, a template for the tip and one for the root, tack glue a load of blanks together and sand the whole lot in one go, then set up spars as shown in fotos

CloudyIFR:
I found the design procedure in this site http://www.b2streamlines.com/OTW.html,check this link

and the download link is

http://www.glide.net.au/on-the-wing3...tware-Windows/

and thanks for all buddies who reply my thread