What was found
LCQ - MAJOR REPAIR - DURING C-17 CHECK EXFOLIATION CORROSION WAS FOUND ON KEEL BEAM LOWER ANGLE IN RT AIR CONDITIONING BAY, BS 540. MAINTENANCE REMOVED 2 EACH ANGLE SUPPORTS FOR ACCESS AND FOUND CORROSION INDICATIONS IN ALL SIX HOLES; REAMED OUT HOLES AND PERFORMED HFEC INSPECTION, 5 HOLES, NO CRACK INDICATION. CRACK FOUND IN AFT HOLE OF HORIZONTAL FLANGE; CUT OUT CRACKED AREA ON KEEL BEAM LOWER ANGLE; PERFORMED ANOTHER HFEC INSPECTION, NO CRACK NOTED. FABRICATED A REPAIR ANGLE, FILLER, STRAP, AND SHIMS; INSTALLED REPAIR PARTS IAW AWA ER 15-5313-03119-SS1.