# SDR TRBA200731

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 12, 2007
- Submitted: June 14, 2007
- Operation: Air carrier
- Aircraft: [N545AT](https://openairdocs.org/aircraft/N545AT), registered now
- Make and model: Aerosp ATR 72-212A
- Registry model: [Aerosp ATR 72-212A](https://openairdocs.org/model/aerospatiale-atr-72-212a) (OpenAirDocs)
- Aircraft serial: 545
- Aircraft time: 15,233 hours, 17,222 cycles
- System (JASC): [2133 · Pressure Regulator/Outflow Valve](https://openairdocs.org/jasc/2133)
- Part: Outflow Valve
- Part number: 2096H010800
- Part serial: 428
- Condition: Failed
- Location: Cabin Pressure
- Stage of operation: DE
- How discovered: O
- Nature of condition: P
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/TRBA200731

## Discrepancy

DURING DESCENT A/C LOST PRESSURIZATION, ALT ON PRESS GAUGE WENT FROM 0 TO CURRENT ALTITUDE.  RATE WENT FROM -500FT (NORMAL) TO THE RATE AT WHICH DESCENDING.  DIFF WENT TO 0.  HUMMING NOISE HEARD FROM BEHIND COCKPIT.  NO ALERT OR CAUTION INDICATING A PROBLEM.  REMOVED AND REPLACED PNEUMATIC OUTFLOW VALVE IAW JIC NR 21-31-22.  REMOVED AND REPLACED MANUAL PRESS CONTROLLER IAW JIC NR 21-32-82.  PERFORMED FUT CK ON GND IAW JIC NR 21-31-00.  OP CK OK.

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