# SDR SWAA2025062382930

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 17, 2025
- Submitted: June 23, 2025
- Operation: Air carrier
- Aircraft: [N8645A](https://openairdocs.org/aircraft/N8645A), registered now
- Make and model: Boeing 737-8H4
- Registry model: [Boeing 737-8H4](https://openairdocs.org/model/boeing-737-8h4) (OpenAirDocs)
- Aircraft serial: 36907
- Aircraft time: 36,350 hours, 17,638 cycles
- System (JASC): [2130 · Cabin Pressure Control System](https://openairdocs.org/jasc/2130)
- Part: Check Valve
- Condition: Inoperative
- Location: Zone 100
- Stage of operation: CL
- How discovered: O
- Nature of condition: J
- Precautionary procedure: B, A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/SWAA2025062382930

## Discrepancy

@APPROX FL190 CABIN ALT ALERT SOUNDED IMMEDIATELY STARTED DECENT TO 10000 FT. CABIN MASKS AUTO DEPLOYED WHILE CREW DOWNING OXYGEN. COMPLETED DECENT W/ QRC & QRH PROCEDURES AND RETURNED TO ORIGIN JAX<[01] DURING INITIAL PACK CONFIDENCE CHECK FOUND GROUND AIR CONDITIONING CHECK VALVE DAMAGED REF TTG8Q0138LR3 FOR REMOVAL AND INSTALLATION. PERFORME3D CABIN PRESSURIZATION CONDITIONAL INSPECTION IAW AMM 05-51-81 REF TTG8Q0137MMM AND PERFORMED EXCESSIVE CABIN PRESSURE LEAKAGE CONDITIONAL INSPECTION IAW MM 05-51-91 REF TTG8Q137 MQ0.

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