SDR UALA2011012700449

Service difficulty report · Buss · Boeing 757222

Difficulty date: January 27, 2011
Submitted: February 17, 2011
Operation: Air carrier
Aircraft: N543UA
Make and model: Boeing 757222
Aircraft serial: 25698
Aircraft time: 73,888 hours, 21,461 cycles
Engine: Pwa PW2040
System (JASC): 2450 · AC Power Distribution System
Part: Buss
Condition: Faulted
Location: Left
Stage of operation: CL
How discovered: O
Nature of condition: J
Precautionary procedure: A

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

LEFT BUSS PROBLEM, RTFL. AFTER ACFT PARKED RESET THE C-B & DID NOT TRIP, INSPECTED ALL WIRING RELATED TO THE SYS IN P6 PANELS, NO LOOSE OR OVERHEATED CONNECTIONS NOTED, REPLACED C/B C326,TRANSFORMER T10040 AND RELAY K10566. RUN BOTH ENG WITH HEAVY ELC LOAD,TESTED HMG, BPCU HAS NO RELATED FAULT HISTORY.