# SDR GTIA2021090335972

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 2, 2021
- Submitted: September 3, 2021
- Operation: Air carrier
- Aircraft: [N670NK](https://openairdocs.org/aircraft/N670NK), registered now
- Make and model: Airbus A321-231
- Registry model: [Airbus A321-231](https://openairdocs.org/model/airbus-a321-231) (OpenAirDocs)
- Aircraft serial: 7106
- Aircraft time: 16,766 hours, 7,188 cycles
- System (JASC): [2133 · Pressure Regulator/Outflow Valve](https://openairdocs.org/jasc/2133)
- Part: Outflow Valve
- Condition: Fluctuates
- Location: Cabin Pressure
- Stage of operation: CL
- 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/GTIA2021090335972

## Discrepancy

IMMEDIATELY AFTER TAKEOFF THE CABIN V/S WAS ERRATIC FROM -900 TO +900FPM. THE OUTFLOW VALVE FLUCTUATED ERRATICALLY FROM PARTIALLY OPEN TO A LITTLE OVER QUATER OPEN RAPIDLY AND THERE WAS A CYCLE CONSISTING OF MUCH AC AIR TO VERY LITTLE AC AIR WITH PAIN TO THE ECIS UP TO FL180.--

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