As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING A ROUTINE INSPECTION SOME PAINT BLISTERING WAS NOTICED ALONG THE LT AFT SPAR UPPER CAP IN THE THE EXPOSED AREA OF THE LT WHEEL WELL. FURTHER INVESTIGATION REVEALED THAT THE SPAR CAP HAD SEVERE EXFOLIATION TYPE CORROSION AND WAS CAUSING THE SPAR CAP TO FLAKE APART. ONCE THE AFT SECTION OF SKIN WAS REMOVED, IT WAS NOTICED THAT THE CORROSION HAD EXTENDED ALL THE WAY THOUGHT THE CAP. INSPECTION OF THE REMAINING SPAR CAPS REVEALED NO CORROSION.