AirplaneDesign.aero

[Will]

I've just started sketching out a design for a homebuilt aircraft with elliptical wings. They won't be perfectly elliptical (assuming I don't decide that they're too big of a headache), I will probably make the wings using the foam and hotwire method and do the wing in 6-8 sections.

I have a number of questions:

1. Is it okay to use the same airfoil from root to tip just scaled down where the wing gets narrower?

2. It seems like it would be very tricky to design the spars without curvature so is there a way to do design them to be straight?

3. Anyone know any good online references for the spitfire or perhaps the P-47 Thunderbolt with info on airfoils used and detailed structural drawings?

Thanks,

Will

[steven42]

Hi Will
The spar in the spitfire is straight. This is achieved by having a ellipse section behind the spar that is about two times the width of the ellipse section in front. As the center of lift is about 1/3 the way back the wing, the lift on each rib is balanced about the spar. The P-47 Thunderbolt looks like it is using the same trick. The elevator of the spitfire seems to use the same shape but reversed. The spar line has become the hinge line for the moving surface. Hope this has been of some help.

Steven42