What was found
FJ33-5A ENGINE SERIAL NUMBER 361138, FROM AIRCRAFT SF50-0236 (N19VJ), WAS RETURNED TO THE REPAIR STATION FOR SCHEDULED CHECK 3 HOT-SECTION MAINTENANCE. TYPICALLY, CHECK 3 MAINTENANCE IS PERFORMED “ON-FUSELAGE”; HOWEVER, ENGINE 361138 WAS SELECTED FOR WILLIAMS INTERNATIONAL’S OPERATION MONITORING PLAN (OMP). OMP REQUIREMENTS INCLUDE “AS-RECEIVED” ENGINE TESTING AND SUBSEQUENT ENGINE DISASSEMBLY BEYOND THE SCOPE OF CHECK 3 REQUIREMENTS. AS-RECEIVED ENGINE TESTING RESULTS REVEALED NOMINAL ENGINE PERFORMANCE CHARACTERISTICS WITH INTER-TURBINE TEMPERATURE (ITT) BEING 6° RANKINE ABOVE THE NEW-ENGINE PRODUCTION ITT LIMIT FOR THE FJ33-5A ENGINE MODEL. DISASSEMBLY OF THE ENGINE’S COMPRESSOR SECTION REVEALED ONE LIBERATED 3RD-STAGE INTERMEDIATE PRESSURE COMPRESSOR (IPC) BLADE. NOTE: THE IPC ROTOR IS A THREE-STAGE AXIAL COMPRESSOR. FURTHER DISASSEMBLY OF THE ENGINE REVEALED DOWNSTREAM SECONDARY DAMAGE TO OTHER ENGINE COMPONENTS.