What was found
DURING C-16 CHECK, CORROSION AND 3 EACH .2500 INCH CRACKS WERE FOUND ON LOWER EXTERIOR FUSELAGE SKIN (LT AND RT KEELBEAM) AT BS 727+5 - BS 727+10, STR 27 LT - STR 27 RT. MAINTENANCE CUT SKIN FOR ACCESS TO KEEL BEAM; TRIMMED OUT DAMAGED AREAS OF OUTBOARD LOWER FLANGE ON KEELBEAM BS 727+5 - BS 727+10, STR 27 LT - STR 27 RT; BLENDED OUT AND TREATED CORROSION; PERFORMED HFEC INSPECTION OF CUTOUTS TO VERIFY NO CRACKS EXIST; FABRICATED A DOUBLER, TRIPLER, FILLER & REPAIR ANGLE FOR LT KEELBEAM, AND FILLER & REPAIR ANGLE FOR RT KEELBEAM; INSTALLED REPAIR PARTS IAW AWA ER.