# SDR ASAA2023101345624

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 13, 2023
- Submitted: October 16, 2023
- Operation: Air carrier
- Aircraft: [N461AS](https://openairdocs.org/aircraft/N461AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 36363
- Aircraft time: 35,853 hours, 11,199 cycles
- System (JASC): [2130 · Cabin Pressure Control System](https://openairdocs.org/jasc/2130)
- Part: Unknown
- Part number: UNKNOWN
- Condition: Unknown
- Location: Unknown
- Stage of operation: DE
- How discovered: V
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2023101345624

## Discrepancy

ON DESCENT WITH POWER AT IDLE UNABLE TO MAINTAIN CABIN ALTITUDE. WITH POWER AT IDLE CABIN ALTITUDE CLIMBS AT 1000 + FPM (UP TO 2000' FPM). GROUNDED - YES. PERFORMED FIM TASK 21-31 TASK 801 FAULT CODE 30 "LO ONFL/HI LEAKG" & FC:31 "ACFT RATE HI" TN 83453 10/12/2023. PREFORMED BITE TEST ON PACK/ZONE TEMPERATURE CONTROLLER REF AMM 21-61-00-700-806-002. TEST PASS. PREFORMED AIRPLANE PACK OPERATAION CONFIDENCE CHECK REF AMM 21-00-05-780-801. CABIN LEAKAGE RATE FALLS INTO OPTIMUM LEVEL. TEST GOOD.

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