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Old 01-31-2003, 04:56 AM
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Ben Lanterman
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Default XFoil and airfoil data

Keep in mind that if you look at the front of the airplane that the lift of the wing carrys across the fuselage in an ellipse (or something roughly like it). A fuselage wide enough to produce a significant amount of lift toward the front will have the pressure distribution reasonably messed up by the relatively large pressure influence from the wing. You end up with something that resembles a wing with a long square lex.

A few years ago a design came out in the model press with a wing that had an aspect ratio of about 5 and a rectangular planform. A fuselage that was about 20% of the span wide was added to the front of the wing and had roughly the thickness of the wing in depth. The nose was a cylindrical section. The tail was mounted on two booms back fron the edge of the fuselage with the stab between them. It was interesting but nothing more was ever mentioned about it.

Basically canards work well because they are separate surfaces with their own wing carryover effects. Think about the real high aspect ratio that Rutan's designs use.

To get a canard effect it is easier to use a canard, lift is best produced by wings, fuselages are good to wrap equipment around but are not too good at lift generation (knife edge taking a lot of sideslip angle)