# SDR 2001UALA01308

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 28, 2001
- Submitted: July 10, 2001
- Operation: Air carrier
- Aircraft: N7446U
- Make and model: Boeing 727222
- Aircraft serial: 21900
- Aircraft time: 58,953 hours, 35,295 cycles
- System (JASC): [3610 · Pneumatic Distribution System](https://openairdocs.org/jasc/3610)
- Part: Valve
- Part number: 39271611MOD
- Condition: Failed
- Location: Nr 3 Engine
- Stage of operation: DE
- How discovered: O
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2001UALA01308

## Discrepancy

CABIN PRESSURE CANNOT BE MAINTAINED IN DESCENT.  *S/D*  SUSPECT NR 3 ENG HIGH PRESSURE MODULATING VALVE.  REPLACED HIGH PRESSURE MODULATING VALVE.

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