As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING C CHECK, CRACK INDICATION ON NR 4 SLAT OUTBOARD ACTUATOR SUPPORT RIB. REMOVED ACCESS PANEL AT NR 4 SLAT IAW SRM 51-30-2. LOCATED AND DRILLED HOLES ON NEW RIB IAW SRM 51-30-5. INSTALLED NEW RIB AT NR 4 SLAT OUTBOARD ACTUATOR IAW SRM 51-30-2. INSTALLED ACCESS PANEL AT NR 4 SLAT IAW SRM 51-30-2.