# SDR COEA0803912

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 5, 2008
- Submitted: October 2, 2008
- Operation: Air carrier
- Aircraft: [N912FX](https://openairdocs.org/aircraft/N912FX), registered now
- Make and model: Aerosp ATR 42-300
- Registry model: [Aerosp ATR 42-300](https://openairdocs.org/model/aerospatiale-aeritalia-atr-42-300) (OpenAirDocs)
- Aircraft serial: 047
- System (JASC): [3440 · Independent Position Determining System](https://openairdocs.org/jasc/3440)
- Part: Indicator
- Part number: 457400TB0811
- Condition: Failed
- Location: Vsi/Tcas
- Stage of operation: CR
- How discovered: O
- Nature of condition: S
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/COEA0803912

## Discrepancy

AIR TURN BACK, ENROUTE, THE CAPT`S VSI FLASHED MOMENTARILY CAUSING A TCAS FAIL AND RESOLUTION ALERT, THEN WENT BLANK. SINCE THE COPILOT`S SYSTEM WAS OPERATING NORMALLY. A DECISION TO RETURN TO DEPARTURE WAS MADE SINCE PARTS WERE AVAILABLE THERE AND MAINTENANCE ALSO COULD BE ACCOMPLISHED. REMOVED AND REPLACED CAPT`S VSI/TCAS INDICATOR. (K)

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