As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT GROUNDED FOR HEAVY MAINTENANCE. CORROSION ON THE FORWARD SIDE OF FRAME 1380 AT THE UPPER SPAR CAP ABOVE STR 27R. CORROSION FRAME 1380 ABOVE STRINGER 27R FOUND OUT OF LIMITS IAW SRM 53-00-07, FIG 101. REPAIR AREA AT FROM 1380 IAW ENGINEERING DOCUMENT 47225REA04.