# SDR 0501096717

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 14, 2005
- Submitted: July 20, 2005
- Operation: Air carrier
- Aircraft: [N617US](https://openairdocs.org/aircraft/N617US), registered now
- Make and model: Boeing 747251F
- Aircraft serial: 21121
- Aircraft time: 99,276 hours, 24,600 cycles
- System (JASC): [2612 · Fire Detection](https://openairdocs.org/jasc/2612)
- Part: Fire Loop
- Condition: Malfunctioned
- Location: Apu Bay
- Stage of operation: CR
- How discovered: O
- Nature of condition: N
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/0501096717

## Discrepancy

DURING CRUISE, APU FIRE LIGHT B LOOP ILLUMINATED WITH BELL.  THEN SELECTED LOOP A.  AIRCRAFT CONTINUED ON TO ANC AND LANDED WITHOUT INCIDENT.  ANC MAINTENANCE PUT APU FIRE LOOP B ON MEL.  18JUL05 SIN MAINTENANCE R&R UPPER FIRE DETECTOR ELEMENTS LOOP A & B.  OPERATIONAL CHECKS OK.

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