# SDR AT0300004

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 22, 2003
- Submitted: February 25, 2003
- Operation: Air carrier
- Aircraft: [N832AT](https://openairdocs.org/aircraft/N832AT), registered now
- Make and model: Doug DC-9-32
- Registry model: [Doug DC-9-32](https://openairdocs.org/model/mcdonnell-douglas-dc-9-32) (OpenAirDocs)
- Aircraft serial: 47451
- System (JASC): [2133 · Pressure Regulator/Outflow Valve](https://openairdocs.org/jasc/2133)
- Part: Outflow Valve
- Condition: Iced
- Location: Cabin Pressure
- Stage of operation: DE
- How discovered: O
- Nature of condition: F
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AT0300004

## Discrepancy

LOST CABIN PRESSURIZATION AT 20,000 FT IN ICING CONDITIONS.  SELECTED MANUAL AND THE VALVE WOULD NOT CLOSE ALL THE WAY.  MASKS DROPPED SUSPECT ICING AFTER 30 MINUTE HOLD.  OPERATED OUTFLOW VALVE AND PRESSURIZED TO 3 PSI, OPS NORMAL REF MM 21-32.  MASK DROPPED CHECK AND REPACK MASK, NO DEFECTS NOTED.

---
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.