# SDR 2005UALA00299

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 5, 2005
- Submitted: April 12, 2005
- Operation: Air carrier
- Aircraft: [N647UA](https://openairdocs.org/aircraft/N647UA), registered now
- Make and model: Boeing 767322
- Aircraft serial: 25284
- Aircraft time: 57,161 hours, 9,384 cycles
- Engine: Pwa PW4060
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: A/C Pack
- Condition: Malfunctioned
- Location: A/C Bay
- Stage of operation: CR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: B, A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2005UALA00299

## Discrepancy

LOSS OF BOTH PACKS CAUSED RESULTANT PRESSURIZATION PROBLEM.  ALTHOUGH RT PACK WAS DEFERRED IN STANDBY MODE PER MEL AT THE TIME OF THE EVENT, THERE IS NO RECORD OF ANY DEFECT OR MAINTENANCE ACTIVITY AGAINST THE LT PACK, PRIOR TO OR AFTER THE EVENT.  RT PACK COMPRESSOR OUTLET TEMP SENSOR AND RT PACK RAM AIR INLET ACTUATOR WERE BOTH REPLACED. MAINTENANCE ALSO REPLACED LT BLEED ISOLATION VALVE DUE TO DAMAGED BUTTERFLY SEAL. HOWEVER, NONE OF THE AVAILABLE DATA EXPLAINS LOSS OF CABIN PRESSURIZATION.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.