As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE IN HEAVY MAINTENANCE PERFORMING INSPECTION IT WAS NOTED THAT THE WING CENTER SECTION RBL 70.5 STRINGER 17R IS CORRODED BETWEEN B.S. 740-760. REMOVED CORROSION, FABRICATED INTERNAL ANGLE FROM 7075 T6 .063" DIM 16.125 X 2.750", EXTERNAL DOUBLER FROM 7075 T6 .071" DIM 24.250" X 3.625". INSTALLED REPAIR, NO OTHER DEFECTS WERE NOTED AIRCRAFT WAS RETURNED TO SERVICE.