As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FWD CARGO TRANSITION AT RBL-21 CORRODED MULTIPLE AREAS BETWEEN STA 500A TO STA 500H+10. GROUNDED - YES. REMOVED CORROSION FOUND TO BE OUT OF LIMITS, REMVOED AND REPLACED FWD CARGO TRANSITION AT R-BL21 STA 500A TO 500H+10 IAW B737-900 SRM 53-00-53-2R-5W= 3" O= .040 R= .000 L= 2" D= .040.