# SDR IPXA2018041028439

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 10, 2018
- Submitted: April 11, 2018
- Operation: Air carrier
- Aircraft: [N457UP](https://openairdocs.org/aircraft/N457UP), registered now
- Make and model: Boeing 757-24APF
- Registry model: [Boeing 757-24APF](https://openairdocs.org/model/boeing-757-24apf) (OpenAirDocs)
- Aircraft serial: 25478
- Aircraft time: 29,144 hours, 17,453 cycles
- System (JASC): [4950 · APU Bleed Air System](https://openairdocs.org/jasc/4950)
- Part: Valve
- Part number: 97980612
- Part serial: 725C
- Condition: Malfunctioned
- Location: Apu
- Stage of operation: CR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/IPXA2018041028439

## Discrepancy

APU FAILED IN FLIGHT,   THE APU FAULT LIGHT AND EICAS ILLUMINATED.  PERFORMED AN APU BITE TEST IAW MM 49-61-05-742-049.   REVERSE FLOW PRESENT ON BITE. IAW FIM 49-11-00-815-880-002-2.  REMOVED AND REPLACED THE  APU SURGE VALVE IAW MM 49-53-01. OPS CHECKED GOOD,  NO FAULTS SHOWN ON APU BITE CHECK.

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