Design considerations

[jhmagill]

Let's say I'm using an enlarged 3-view to build a plane out of Depron. I plan on building an
under cambered wings airfoil by curving the foam over the edge of a counter. What
design considerations do I need to make going from a full profile airfoil to a
thin, under cambered airfoil? Do I need to increase the wing incidence? Do I
leave it alone? Do I need to make any changes to the tail incidence?
I'm looking at some WWI bi-planes and want to build a nice,easy flying plane around 1:10 scale (28" to 35").
What other design issues are there when building from 3-views?

Thanks

[slipstick]

Most WW1 biplanes start off with an "under-cambered" airfoil (not the correct technical description but most people understand it) so that's no big difference. You're effectively using a fairly high lift, high drag airfoil and that's what they're designed with.

And like the rest of us you'll have to set the incidences by trial and error. There's no particular reason why they would change.

You'll also have to decide whether to use accurate scale outlines and sizes. E.g. many "scale" models use larger tail surfaces than is strictly correct.....just because they fly better like that. But things like that are general design aspects, nothing to do with the building material you're using ;).

Steve

[BMatthews]

There's no need to make any significant alteration due to the cambered depron. Just go with the "normal" incidence angles you would use normally.