Service difficulty report · Wire · Boeing 747422

Difficulty date
May 8, 2010
Submitted
May 13, 2010
Operation
Air carrier
Aircraft
N182UA
Make and model
Boeing 747422
Aircraft serial
25279
Aircraft time
78,628 hours, 9,627 cycles
Engine
Pwa PW4056
Part
Wire
Part number
W350803318
Condition
Damaged
Location
Oil System
Stage of operation
NR
How discovered
O
Nature of condition
B
Precautionary procedure
O

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

What was found

NR 4 ENG HAS NO OIL PRESSURE INDICATION, BREAKER D4 WAS POPPED. FOUND MULTIPLE WIRES BURNED AND ARCING ON WIRE HARNESS 10 INCHES AFT OF TRANSMITTER. BUNDLE WAS DAMAGED BY COOLING VALVE MOUNTED ON INBOARD SIDE OF FAN COWL. WIRE HARNESS IS FOR OIL PRESSURE TRANSMITTER AND LOP TRANSMITTER. COLLARED AND TAGGED BREAKER D4. WIRES W3508-033-18 AND W3508-031-18 ARE DAMAGED. REPAIRED IAW MM. WIRES WERE REPARIED WITH SPLICES. HARNESS WAS REPOSITIONED TO PREVENT CONTACT WITH NACELLE VENTILATION VALVE. WILL NEED TO REPLACE WIRES WHEN HARNESS IS REMOVED OR ENGINES NEXT SHOP VISIT.