What was found
DURING HEAVY CHECK, MAINTENANCE FOUND RIGHT HAND HORIZONTAL STABILIZER RIB 11 AT FRONT AND MIDDLE SPAR HAS A CRACK. REMOVED DAMAGED RIB 11 FROM RT HORIZONTAL STAB. LOCATED, DRILLED, ALODINED AND INSTALLED NEW RIB 11 ON RT HORIZONTAL STAB REF SRM 51-40-08, 51-41-01, 51-41-02.