Service difficulty report · Relay · Boeing 747422

Difficulty date
October 4, 2012
Submitted
October 18, 2012
Operation
Air carrier
Aircraft
N178UA
Make and model
Boeing 747422
Aircraft serial
24385
Aircraft time
91,567 hours, 11,033 cycles
Engine
Pwa PW4056
Part
Relay
Condition
Failed
Location
Cockpit
Stage of operation
IN
How discovered
O
Nature of condition
B
Precautionary procedure
K

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

What was found

CREW REPORTS THE FOLLOWING CB'S WERE FOUND OPEN UPON ARRIVAL TO FLT DECK. GRID A11, C10, C12, E11, A6 ALL ON THE OVERHEAD. CREW ALSO NOTED SLIGHT ELECT ODOR IN FLT DECK. ALL OF THE C/B'S ABOVE WERE ON THE 115VAC STBY BUS. FOUND MAIN STATIC INV INOP AND DAMAGED STBY PWR TRANSF RELAY BEHIND COCKPIT P6 PANEL AND FOUND LEFT EFIS CONTROL PANEL INOP. REPLACED ALL, STBY POWER TEST CHECKS NORMAL NOW, ALL C/BS STAY IN, NO SMELL NOTED. OK FOR SERVICE.