What was found
DURING C1 CHECK, MAINTENANCE FOUND KEEL BEAM CHORD UPPER SURFACE RH SIDE STA 999 HAS CORROSION. EVALUATED KEEL BEAM CHORD UPPER SURFACE R/H SIDE AT STA 999, REMOVED CORROSION, FABRICATED 1EA RETAINER, SHOT PEEN REMOVED AREA, TREAT AND PRIME 1 EA RETAINER AND REWORKED AREA INSTALLED RETAINER IAW B767-200 SRM 53-50-12-REPAIR AND ENGINEERING #145T8610-1. AIRCRAFT RETURNED TO SERVICE AFTER C1 CHECK COMPLETED.