As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MCN - MAJOR REPAIR - DURING C-16 CHECK DISCOVER 4 CRACKS IN BOTTOM OF THE NR 5 SLAT SKIN AT SS 163 TO SS 174. MAINTENANCE REMOVED DAMAGED AREA IAW BOEING 737-300 SRM 57-43-01-2. FABRICATED REPAIR FILLER AND SPLICE PLATE IAW BOEING 737-300 SRM 57-43-01. INSTALLED FABRICATED REPAIR PARTS IAW BOEING 737-30051-40-02-0 FIG 14.