As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CORROSION FOUND AT LAV DUMP PAN AREA. RMVD CORRODED FRAMES & INTERCOSTALS. CKD INNER SKIN-NO DISCREPANCIES - OK TO REPLACE CORRODED PARTS. INSTALLED NEW FRAMES & INTERCOSTALS PER SRM 51-30-02 & EO B747-5330-23587A. DRILLED RT INTERCOSTAL FROM HOLES, DRILLED LH INCOSTAL FROM HOLES. INSTALLED RT & LH INTERCOSTAL PARTS ALSO INSTALLED DUMP CHUTE.