Hi no-hoper,
Thanks for the information and correction of the wing manufacturing video. I think you are correct relative to the panel being placed against the ribs, it would appear to be an underside of the wing panel.
blakmax,
What you are seeing wrapped in the plastic bag is the wing panel including the fixture it is resting on. The fixture defines the desired shape (contour) that will
be established by the "baking process". After removal from the autoclave the wing panel is removed from the fixture. The skin is not bonded to the ribs per-se, but bolted using fasteners. For the composite ribs, a special fastner or bolt was designed by Alcoa working with Airbus for fastening metal to composite, see a picture of it below which was contained in an magazine article about Alcoa.
I am not sure the slabs or thick plates, from which the ribs are machined, are rolled at all. If they are not, the grains would have random orientations based upon the solidification pattern. Repair of the cracks, assuming they are readily assessable, might be acomplished by welding as the alloy, IMO, is weldable by TIG or Stir welding processes.
Machaca,
Thanks for all the information you have provided. Airbus' Charles Champion's remarks concerning the dispersion of cracking makes for an interesting search process I would think!