As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPPER SPAR CAP WAS FOUND WITH SEVERE EXFOLIATION CORROSION BEHIND THE FUEL TANK. TANK WAS PULLED TO COMPLY WITH SB. THERE WAS NO INDICATION OF CORROSION SWELLING ON THE SURFACE OF THE WING. THE AREA WHERE THE CORROSION OCCURRED IS NOT VISIBLE FROM INSPECTION PANEL ACCESS AND REQUIRES THAT THE FUEL TANKS BE PULLED FOR INSPECTION OF THIS AREA. MFG HAS ADDRESSED THIS IN SB. (K)