What was found
AT TOP OF DESCENT GOT INTERMITTENT THEN STEADY LOOP A LT NR 3 ENG FOLLOWED RED TABS TESTED LOOP-B TEST FAILED FOLLOWED ENG FIRE SEVERE DAMAGE CHECKLIST SHUTDOWN NR 3 ENG FIRE INDICATIONS CONTINUED UNTIL AFTER SHUTDOWN. FOUND 9TH STAGE METAL GASKET BLOWN OUT, WHICH CAUSED HOT AIR TO BE BLOWN ON THE -A- AND -B- FIRE LOOPS. REMOVED AND REPLACED GASKET PER STANDARD MAINT PRACTICES. FOUND NO FAULTS WITH -B- LOOP, OPS CHECK NORM PER M/M 26-10-00-5. INSP TIN FOIL ON DUCT JOINTS, NO DAMAGE FOUND. NR 3 ENG WAS RAN PER JRH, NO FAULTS NOTED ON IDLE ENG RUN. REOPENED ENG AND INSP DUCTS, NO FAULTS NOTED, ENG COWLINGS ARE CLOSED PER M/M 71-00-00-2. OK FOR SVC.