# SDR DALA2024120311411

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 2, 2024
- Submitted: December 3, 2024
- Operation: Air carrier
- Aircraft: [N944DZ](https://openairdocs.org/aircraft/N944DZ), registered now
- Make and model: Boeing 737-9GPER
- Registry model: [Boeing 737-9GPER](https://openairdocs.org/model/boeing-737-9gper) (OpenAirDocs)
- Aircraft serial: 38729
- Aircraft time: 30,514 hours, 12,488 cycles
- System (JASC): [2131 · Cabin Pressure Controller](https://openairdocs.org/jasc/2131)
- Part: Control Valve
- Condition: Abnormal
- Location: Left Pack Flow C
- Stage of operation: CR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: B
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DALA2024120311411

## Discrepancy

SHIP 3944 -PRESS/DE- DECLARED EMERGENCY DUE TO UNABLE TO MAINTAIN CABIN PRESSURE ON RIGHT PACK. LEFT PACK ON MEL. CORRECTIVE ACTION: REPLACED RIGHT PACK STANDBY TEMP CONTROL VALVE AND LEFT PACK FLOW CONTROL VALVE. BOTH PACKS PASS SINGLE PACK CONFIDENCE CHECKS. OPS CHECK GOOD.

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