# SDR UIEA2012121700553

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 17, 2012
- Submitted: December 17, 2012
- Operation: Air carrier
- Aircraft: [N418MC](https://openairdocs.org/aircraft/N418MC), registered now
- Make and model: Boeing 747-47UF
- Registry model: [Boeing 747-47UF](https://openairdocs.org/model/boeing-747-47uf) (OpenAirDocs)
- Aircraft serial: 32840
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Valve
- Condition: Malfunctioned
- Location: Smoke Overide
- Stage of operation: IN
- How discovered: V
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UIEA2012121700553

## Discrepancy

MX PICKUP SMOKE OVERRIDE VALVE OPEN.  REMOVED VALVE FOR TROUBLESHOOTING, FOUND BUTTERFLY SHAFT SHEARED.  INSTALLED SMOKE/OVERRIDE VALVE IAW MM 21-58-06.   GROUND TEST - OK IAW TASK 21-58-00-705-001.

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