# SDR KCSA20200727411

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 24, 2020
- Submitted: July 27, 2020
- Operation: Air carrier
- Aircraft: [N707CK](https://openairdocs.org/aircraft/N707CK), registered now
- Make and model: Boeing 747-4B5
- Registry model: [Boeing 747-4B5](https://openairdocs.org/model/boeing-747-4b5) (OpenAirDocs)
- Aircraft serial: 26395
- Aircraft time: 95,164 hours, 16,832 cycles
- System (JASC): [2130 · Cabin Pressure Control System](https://openairdocs.org/jasc/2130)
- Part: Cabin Pressure
- Condition: Malfunctioned
- Stage of operation: CR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/KCSA20200727411

## Discrepancy

CABIN ALT AUTO.  UNABLE TO BRING CABIN DOWN MANUALLY, GRADUAL DECOMPRESSION OF CABIN. PERFORMED CABIN PRESSURE CONTROL TEST ON CPCS-A AND CPCS-B.  BOTH PASSED AND PERFORMED CABIN PRESSURE CONTROL SYSTEM CABIN PRESSURIZATION GROUND TEST.  NO LEAKS FOUND IAW AMM 21-31-00.

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