# SDR AMCR201010

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 28, 2010
- Submitted: October 28, 2010
- Operation: General aviation
- Filed by: [Alticor Inc, repair station AMCR163C](https://openairdocs.org/faa-repair-station/AMCR163C/alticor-inc.md) (OpenAirDocs)
- Aircraft: [N254DV](https://openairdocs.org/aircraft/N254DV), registered now
- Make and model: Bombdr BD1001A10
- Aircraft serial: 20262
- Aircraft time: 367 hours, 291 cycles
- System (JASC): [2130 · Cabin Pressure Control System](https://openairdocs.org/jasc/2130)
- Part: Actuator Valve
- Part number: 4485253
- Part serial: 391
- Condition: Faulty
- Location: Cabin Pressure
- Part time: 367 hours, 291 cycles
- Stage of operation: DE
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AMCR201010

## Discrepancy

DURING DESCENT, PASSING THROUGH FL410, CABIN OXYGEN MASKS DEPLOYED. THERE WAS NO WARNING OR INDICATION. CABIN PRESSURE WAS FINE. AFTER MASKS DEPLOYED, CREW GOT THE NORMAL INDICATION WHICH WAS A CAS MSG THAT "PAX OXY ON". REPLACED ELECTRO-PNEUMATIC ACTUATING VALVE (EPAV) AND TESTED SYS WITH ALL NORMAL OPERATION.  BUT, THE REPLACEMENT VALVE'S 'SHOP FINDING REPORT' FROM STATED THE VALVE WAS INSPECTED AND TESTED WITH 'NO FAULT FOUND' AND HAD A HISTORY STATING THE PREVIOUS REASON FOR REMOVAL WAS AN INTERNAL OXYGEN LEAK INTO THE PAX SYS CAUSING DEPLOY MODE. NO CONFIDENCE IN REPLACEMENT VALVE (SN 218) SO ANOTHER REPLACEMENT TO BE INSTALLED.

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