As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CORROSION WAS FOUND ON INTERNAL AND EXTERNAL SKIN SURFACE AT LAV TUB CUTOUT (LT) STA 2090. S-35L - S-36L. S: 1"X0.8- BLEND OUT THE CORROSION, RECORD SIZE, REPLACED THE INTERNAL DOUBLER AND RESTORED SURFACE TREAT, AND PAINT PER B747-400 SRM 53-00-01 ALLOWABLE DAMAGE 1. FIG 101 AND B747-400 SRM 51-40-02 P1 ORIG.MAT.0.071" DAMAGE DIM.L1.22" W1.01"D0.004.