I was just wondering about dihedral. I understand that it makes the plane have 'self-righting characteristics' and is used extensively on trainers. What about negative dihedral? I saw a plane at the airport the other day - it was a huge, high-wing cargo plane (military), and the wings seemed to have the opposite of dihedral, where they were higher at the center and pitched down. How would this affect flying, and how does dihedral work in the first place?

What I'm guessing is that the lower the body of the plane hangs below the wings, there is a larger moment created by gravity pulling down on the plane about the axis, which I guess would be through the point there the wings are joined to the plane. Maybe with the reverse pitched dihedral there is a cancellation of the self-righting/moment for the big, heavy plane, so it is a little more nimble???

What do I know.