What was found
LVL 3 ENG 3 FIRE ALERT ILLUMINATED DURING CLIMBOUT, PASSING FL220. C/W QRH. EMERGENCY DECLARED. NR 3 ENGINE FAN & REVERSER COWLS, FOUND NO EVIDENCE OF FIRE OR OVERHEAT, INSPECTED LOOP`S. WHEN CREW PULLED BACK THROTTLE, FIRE ALERT WENT AWAY & SHUTDOWN ENG INFLT, FIRED FIRE BOTTLE AFTER BLOCK IN. FAILED UPPER LT FIRE DET ASSY LOOP A, FOUND IN NR 3 ENG, LT UPPER TURBINE RAIL FIRE LOOP RAIL ASSY BROKEN, BOTH LOOPS BENT 90 DEGREES AT RAIL BREAK, REMOVED AND REPLACED THE LH UPPER TURBINE FIRE DETECTOR ON NR 3 ENG IAW MM 26-11-03-4-1 & PERFORMED FDCU BITE CHEACK IAW MM 26-11-02-5-0. ALL TESTS PASSED, NO CURRENT FAULTS FOUND.