What was found
DURING AN A, B, AND C INSPECTION, FOUND THE HORIZONTAL STABILIZER MOUNTING FACES NOT PARALLEL WITH THE VERTICAL STABILIZER, HORIZONTAL STABILIZER ROLLER CLEARANCE CHECKS IAW MM 27-40-00 OUT OF SERVICE LIMITS. INSPECTED STABILIZER IAW MFG COMMUNIQUÉ NR 70 AND FOUND RT HORIZONTAL STABILIZER RIB, PN 45A21104012, CRACKED. REPLACED RIB AND REINSTALLED STABILIZER, HORIZONTAL STABILIZER ROLLER CLEARANCE CHECKS NOW WITHIN SERVICE LIMITS. IAW COMMUNIQUÉ NR 70, ROLLER GAP DIMENSIONS OUT OF SERVICE LIMITS MAY BE CONTRIBUTING TO PROBLEM. AFFECTED STRUCTURE HAS NOT YET BEEN INCLUDED IN SCHEDULED INSPECTIONS GUIDE. (K)