As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING INSPECTION FOR CRACKS ON THE RIB FLANGES OF THE HORIZONTAL STAB ASSY, THE RIB DESCRIBED BELOW WAS FOUND CRACKED (ALONG WITH 7 OTHER RIBS; EA RIB FAILURE IS DOCUMENTED ON SEPARATE SDR FORMS) ON THE LOWER FLANGE AT RT HORIZONTAL CANTED STA 29.92, BETWEEN THE FWD AND AFT SPARS. CRACKS EMANATE FROM THE FASTENER HOLES. THE RIBS WERE REPLACED IAW MFG KIT 128-6200-001.