# SDR 2005UALA01163

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 18, 2005
- Submitted: October 25, 2005
- Operation: Air carrier
- Aircraft: [N556UA](https://openairdocs.org/aircraft/N556UA), registered now
- Make and model: Boeing 757222
- Aircraft serial: 26650
- Aircraft time: 44,730 hours, 16,405 cycles
- Engine: Pwa PW2037
- System (JASC): [2130 · Cabin Pressure Control System](https://openairdocs.org/jasc/2130)
- Part: Relief Valve
- Condition: Open
- Location: Cabin Pressure
- Stage of operation: CR
- How discovered: O
- Nature of condition: W
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2005UALA01163

## Discrepancy

LOSS OF CABIN PRESSURE.  LOWER POSITIVE PRESSURE RELIEF VALVE FOUND OPEN.  REPLACED VALVE, OPS CHECKED OK.  RETURNED AIRCRAFT TO SERVICE.

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