SDR UALA2010040801180

Service difficulty report · Fire Loop · Boeing 747422

Difficulty date: April 8, 2010
Submitted: April 9, 2010
Operation: Air carrier
Aircraft: N181UA
Make and model: Boeing 747422
Aircraft serial: 25278
Aircraft time: 78,252 hours, 9,621 cycles
Engine: Pwa PW4056
System (JASC): 2612 · Fire Detection
Part: Fire Loop
Condition: Faulty
Location: Nr 1 Nacelle
Stage of operation: IN
How discovered: 9
Nature of condition: O
Precautionary procedure: K

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

What was found

'ENG 1 FIRE LP B' EICAS STATUS MSG DISPLAYED. ENG 1 FIRE LOOP B FIRE OR FAULT OUTPUT. FAULT HAS OCCURED IN CRUISE, SUSPECT WIRING CHAFED. CHK NR1 ENG FIRE LP -B- WIRING UNDER EA-CLAMP FOR CHAFING, RING OUT FOR SHORTS-GND & RESIST REF FIM 26-11TSK852, REPAIR AS REQUIRED. PERFORMED INSP, CKD IAW MM. FOUND DETECTOR RESPONDER'S CERAMIC HSG AT LOWER FWD TS683 IS BROKEN. PART NEEDS TO BE REPLACED AS PART BECOMES AVAILABLE.