IMHO, considering incidence is measured with respect to chord line, making
the spar perpendicular to the chord would make it easier (mathematically) to
select the strut lengths. Having said that, I don't think it is hard at all
to figure out what the lengths would be in case the spar was perpendicular
to the bottom of the airfoil.
Ameet
On Thu, Nov 19, 2009 at 6:54 AM, vman1922 <kkamp72@comcast.net> wrote:
>
> In the layout of a 612 rib template I am not sure what to use as a vertical
> reference for the spar. Should it be 90 degrees from the cord line or 90
> degrees from the bottom wing surface????????
>
> I believe this would also affect the angle of incidence.
>
> Thanks! You all make this a great place to exchange info!
>
>