# SDR 2009F00060

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 26, 2009
- Submitted: August 26, 2009
- Operation: General aviation
- Aircraft: [N350FW](https://openairdocs.org/aircraft/N350FW), registered now
- Make and model: Beech 300BEECH
- Aircraft serial: FL421
- Aircraft time: 1,566 hours, 1,376 cycles
- System (JASC): [2132 · Cabin Pressure Indicator](https://openairdocs.org/jasc/2132)
- Part: Switch
- Part number: 10138402833
- Part serial: 298
- Condition: Out Of Tolerance
- Location: Barometric
- Part time: 1,566 hours, 1,376 cycles
- Stage of operation: IN
- How discovered: 9
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2009F00060

## Discrepancy

DURING SCHEDULED 12-MONTH TESTING OF CABIN ALTITUDE WARNING SYS NOTED ANNUNCIATOR INDICATION COMING ON AT 9,940 FT ALTITUDE; BELOW 10,000 FT MINIMUM SERVICE LIMIT ALTITUDE.  REPLACED PN 101-384028-33 BAROMETRIC SWITCH WITH IMPROVED PN 101-384028-47 SWITCH ASSY.  HAVE NOTED SAME OLDER PN SWITCH TO FAIL OUT-OF-TOLERANCE IN OTHER SERIES ACFT.  RECOMMEND MFR ISSUE A RECOMMENDED TYPE SB TO REPLACE OLDER STYLE BAROMETRIC SWITCHES WITH IMPROVED PN SWITCH.

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