# SDR IPXA2022111456334

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 11, 2022
- Submitted: November 16, 2022
- Operation: Air carrier
- Aircraft: [N573UP](https://openairdocs.org/aircraft/N573UP), registered now
- Make and model: Boeing 747-44AF
- Registry model: [Boeing 747-44AF](https://openairdocs.org/model/boeing-747-44af) (OpenAirDocs)
- Aircraft serial: 35662
- Aircraft time: 53,326 hours, 8,355 cycles
- System (JASC): [2612 · Fire Detection](https://openairdocs.org/jasc/2612)
- Part: Fire Warning
- Condition: False Activation
- Location: Apu Bay
- Stage of operation: CR
- How discovered: O
- Nature of condition: N
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/IPXA2022111456334

## Discrepancy

DIVERSION,  DECLARED A MAYDAY, PAN PAN.  APU FIRE MESSAGE DURING CRUISE AFTER BOTTLE DISCHARGE OF APU FIRE BOTTLE.  APU FIRE INDICATION WAS STILL ON INTERMITTENT.  THE FIRE BELL WOULD NOT SILENCE.  REFERENCE TASK I.D.# T3F18E000LR1W & T3F18E000LR20.  OPERATIONAL CHECK GOOD ALONG WITH ALL DMP'S REVERSED & MEL'S C/W.  REPLACED W720-451-18R BETWEEN CONNECTOR D63P TO T1814 PER SWPM 28-10. OPS CKS PER AMM 26-15-00-501.  ORIG SUB DATE:  11/14/2022

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