# SDR 9809499621

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 9, 1998
- Submitted: March 26, 2000
- Operation: Air carrier
- Aircraft: N621NW
- 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: 47544
- System (JASC): [2170 · Humidity Control System](https://openairdocs.org/jasc/2170)
- Part: Coalescer Bag
- Condition: Dirty
- Location: Cabin
- Stage of operation: CR
- Nature of condition: O
- Precautionary procedure: B
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/9809499621

## Discrepancy

AT FL280, THE CABIN PRESSURE CLIMBED RAPIDLY.  THE FLIGHT CREW INITIATED AN EMERGENCY DESCENT TO 10,000 FEET AND GAINED CONTROL OF CABIN PRESSURIZATION.  NO FURTHER PROBLEMS WERE NOTED AND THE AIRCRAFT LANDED AT DESTINATION WITHOUT INCIDENT.  MAINTENANCE REPLACED THE LEFT WATER SEPARATOR AND RIGHT COALESCER BAG.  OPERATIONAL CHECK NORMAL.

---
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.