# SDR UALA2011050202139

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 1, 2011
- Submitted: May 27, 2011
- Operation: Air carrier
- Aircraft: [N791UA](https://openairdocs.org/aircraft/N791UA), registered now
- Make and model: Boeing 777222
- Aircraft serial: 26933
- Aircraft time: 60,049 hours, 8,797 cycles
- Engine: Pwa PW40903
- System (JASC): [4950 · APU Bleed Air System](https://openairdocs.org/jasc/4950)
- Part: Check Valve
- Condition: Malfunctioned
- Location: Apu
- Stage of operation: NR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UALA2011050202139

## Discrepancy

FLIGHT CREW REPORTS "APU BLEED AIR" MESSAGE ON APU START UP.  CHECK APU CHECK VALVE OPEN & CLOSE FREELY, CLEANED PRESSURE SENSOR.  ERASED STATUS MESSAGE & START APU CHECK NO STATUS MESSAGE & MAINT.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.