As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT IN BASE MAINTENANCE: NOTICED 2EA CRACKS ON INTERNAL STRUCTURE MAIN RIB STIFFENERS 1ST AND 2ND FROM FWD TO AFT LOWER END INBD SIDE STAB STA 92.70. REMOVED AND REPLACED RIB ASSY ON RH HORIZONTAL STABILIZER INTERNAL STRUCTURE STA 92.70 IAW SRM 51-40-02 AND BOEING DWG 182A5301.