# SDR AALA202608188620

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 15, 2026
- Submitted: August 18, 2026
- Operation: Air carrier
- Aircraft: [N184US](https://openairdocs.org/aircraft/N184US), registered now
- Make and model: Airbus A321-211
- Registry model: [Airbus A321-211](https://openairdocs.org/model/airbus-a321-211) (OpenAirDocs)
- Aircraft serial: 1651
- Aircraft time: 78,417 hours, 30,613 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Bypass Valve
- Part number: 758A000002
- Condition: Overheated
- Location: Zone 100
- Stage of operation: CL
- How discovered: O
- Nature of condition: M
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA202608188620

## Discrepancy

AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED AND THE AIRCRAFT RETURNED TO DFW DUE TO THE FLIGHT CREW REPORTING WITH THE RIGHT PACK ON MEL THAT DURING CLIMBOUT THE LEFT PACK OVERHEATED RESULTING IN THE LOSS OF THE REMAING PACK LEADING TO A LACK OF PRESSURIZATION - THE AIRCRAFT LANDED SAFELY AT DFW WITHOUT FURTHER INCIDENT - MAINTENANCE REPLACED THE TURBINE BYPASS VALVE 10HH ON THE LEFT PACK PER AMM 21-63-53

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