# SDR P5CA9800748

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 31, 1998
- Submitted: March 26, 2000
- Operation: Air carrier
- Aircraft: [N850FT](https://openairdocs.org/aircraft/N850FT), registered now
- Make and model: Boeing 747122
- Aircraft serial: 19755
- System (JASC): [3610 · Pneumatic Distribution System](https://openairdocs.org/jasc/3610)
- Part: Isolation Valve
- Part number: 39831021
- Condition: Inoperative
- Location: Left
- Stage of operation: TX
- Nature of condition: O
- Precautionary procedure: D
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/P5CA9800748

## Discrepancy

LOW DUCT PRESS ON LEFT WING DURING START.  ISOLATION VALVE DOES NOT CLOSE.  REMOVE AND REPLACED ISOLATION VALVE.  OPS CHECK GOOD IAW MM 36-11-07.

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