What was found
TPE/ANC - FLT GT386 - AFTER TAKEOFF, NR 2 GENERATOR FIELD AND MAIN BREAKER TRIPPED FOLLOWED BY NR 2 BUS TIE BREAKER TRIP. ONE MINUTE LATER, NR 1 GENERATOR FIELD AND MAIN GEN BREAKER TRIPPED. COULD NOT RESTORE EITHER GENERATOR. RESET NR 2 BTB AND THE NR 1 BTB TRIPPED AND COULD NOT BE RESTORED. 20 MINUTES LATER, NR 3 BTB TRIPPED, DUMPED FUEL RETURNED TO TPE. APPROACH AND LANDING UNEVENTFUL. DURING T/S, TPE MAINT FOUND NR'S 1, 2, AND 3 GENERATOR CONTROL UNITS DEFECTIVE. REPLACED 3 GCU'S ALL ENG RUN-UP AND NR'S 1 AND 2 GENERATOR CHKS NORMAL. NR 2 GEN INOP, DEFERRED MEL ITEM 24-1. MAINT REPLACED NR 2 GEN AND NR 2 GCU AGAIN. OPER NORMAL. (X)