# SDR DALA2026091605170

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 11, 2026
- Submitted: September 16, 2026
- Operation: Air carrier
- Aircraft: [N709TW](https://openairdocs.org/aircraft/N709TW), registered now
- Make and model: Boeing 757-2Q8
- Registry model: [Boeing 757-2Q8](https://openairdocs.org/model/boeing-757-2q8) (OpenAirDocs)
- Aircraft serial: 28168
- Aircraft time: 92,148 hours, 24,451 cycles
- Engine: Pwa PW2037
- Engine time: 67,436 hours, 20,320 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Shutoff Valve
- Condition: Faulted
- Location: Zone 100
- 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/DALA2026091605170

## Discrepancy

ATB- DUE TO CABIN ALT WARNING CAUSED FROM LEFT BLEED TRIP CAUSING LEFT PACK OFF WITH RIGHT PACK ON MEL. O2 MASKS DEPLOYED.   REPLACED HPSOV. REPLACED FAN AIR TEMP SENSOR AND OVER TEMP SENSOR. OPS CHECK NORMAL. (8644527) (AIRCRAFT GROUNGED)

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