>nor as heavy. If you have the dihedral begin at the fuselage, then the spar has to be alot stronger, and therefore heavier. If this is true, and I don't have reason to doubt him, then basically doing away with the stub wing and beginning the dihedral at the fuselage will require a significantly stronger spar to carry the additional loads. Not being an engineer, I don't know the
You know that when you are in a turn, your wings have to produce more lift perpendicular to the wing to result in the same vertical force... The same occurs with dihedral angle. Both wings are in a constant bank, but towards each other, therefore wings with dihedral must produce more lift than wings without dihedral to achieve the same vertical force, and hence, must be built stronger. According to my number crunching, during straight and level, a 5 degree dihedral carries 1.00382 times to load of a wing with no dihedral. 10 degrees carries 1.0154 times the load. (My formula was just 1/cos(5 deg)) Those numbers lead me to believe that the real problem is that when you have a dihedral, you have a joint in the middle of your spar, where the bending moment is the largest (right under your seat). So, in order to beef this joint up enough to have the same strength as a straight spar takes a bit of weight---think about how heavy the joint is where you connect the outer wings to the stub wings. Perhaps I'm wrong, but the above is the reason I'm not persuing dihedral throughout my entire wing. Mark Youkey myou...@cox.net Oklahoma City
