# SDR DALA2025090406543

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 3, 2025
- Submitted: September 4, 2025
- Operation: Air carrier
- Aircraft: [N821DX](https://openairdocs.org/aircraft/N821DX), registered now
- Make and model: Boeing 757-26D
- Registry model: [Boeing 757-26D](https://openairdocs.org/model/boeing-757-26d) (OpenAirDocs)
- Aircraft serial: 33961
- Aircraft time: 57,557 hours, 27,731 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: A/C Pack
- Condition: Failed
- Location: Zone 100
- Stage of operation: CR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: G, A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DALA2025090406543

## Discrepancy

DIV/PRES/DE- TO YUL DUE TO LOSS OF BOTH PACKS WITH CABIN ALTITUDE WARNING AND O2 MASKS DEPLOYED.   SECURED RT PACK V-BAND CLAMP TO SEC HEAT EXCHANGER, RESECURED COUPLING AT PACK PRIM HEAT EXCHANGER, R/R HOSES AND CLAMPS FROM ACM TO CONDENSER.

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