ORIGINAL: plugin
bkdavy, now that you're on the subject of airfoils let me know if I get this right: The dihedral causes the plane to level itself when on straight line. The symmetry of the airfoil will determine if the plane flies straight inverted or if it needs a little elevator. Right?
Sort of..........
Dihedral helps level the wings when one is higher than the other. The tail helps "the plane to level itself" when the nose is too high or too low.
The airfoil being symmetrical will usually decrease the amount of elevator needed when the airplane is inverted. Airplanes with symmetrical airfoils almost always need different elevator deflection right side up versus upside down.