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-19 CHECK 4 EACH .5 INCH CRACKS WERE FOUND AT RIVET HOLES IN NR 4 SLAT BETWEEN SLAT STA 64.25 AND 78.25. MAINTENANCE CUT OUT CRACKS IN NR 4 SLAT 45.5 TO 61.5 INCHES FROM INBOARD END; FABRICATED A FILLER AND SPLICE PLATE; INSTALLED REPAIR PARTS IAW B737-300 SRM 57-43-01 FIG 206.