# SDR DTHA2008001

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 11, 2008
- Submitted: March 6, 2008
- Operation: Air carrier
- Aircraft: [N407FJ](https://openairdocs.org/aircraft/N407FJ), registered now
- Make and model: Dorner DO328300
- Aircraft serial: 3157
- System (JASC): [2133 · Pressure Regulator/Outflow Valve](https://openairdocs.org/jasc/2133)
- Part: Outflow Valve
- Condition: Dirty
- Location: Cabin Pressure
- Stage of operation: CR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DTHA2008001

## Discrepancy

EN ROUTE DTW TO CLT AT FL310 UNCOMMANDED CABIN ALTITUDE CLIMB TO 9100'.  MAINTENANCE DETERMINED PNEUMATIC OUTFLOW VALVE/FILTER ASSY CONTAMINATED.  VALVE AND FILTERS CLEANED, FUNCTION RESTORED.

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