I saw a C-5 Galaxy fly overhead while visiting relatives in Delaware last November. I couldn't believe it hung in the air, more a feat of sheer engine power than aerodynamics, like a paper airplane made out of brick. Of course, that's what it's designed for: hauling. I don't know how accurate my intuition of flying machines may be, but I doubt there's much ability to recover from mechanical failure. One crashed yesterday. Everyone survived: congratulations to the crew.