# SDR UIEA200400119

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 28, 2004
- Submitted: July 14, 2004
- Operation: Air carrier
- Aircraft: [N522MC](https://openairdocs.org/aircraft/N522MC), registered now
- Make and model: Boeing 747-2D7B
- Registry model: [Boeing 747-2D7B](https://openairdocs.org/model/boeing-747-2d7b) (OpenAirDocs)
- Aircraft serial: 21783
- Engine: Ge CF650E2
- System (JASC): [3440 · Independent Position Determining System](https://openairdocs.org/jasc/3440)
- Part: Indicator
- Condition: Malfunctioned
- Location: Hsi
- Stage of operation: CL
- How discovered: O
- Nature of condition: O
- Precautionary procedure: J, A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UIEA200400119

## Discrepancy

DURING CLIMB, WHEN CLEARED INS WAYPOINT AND SELECTING INS MDU, CDI ON C/A AND F/O HSI WOULD NOT CENTER X WHEN CLEARED VOR AND SELECTING ON INS MDU, HSI SHOWED ABOUT 30 DEGREE DIFFERENCE IN UPDATE.  EXCESSIVE DIFFERENCE IN DRIFT ON ARRIVAL .  23400 FUEL DUMPED.  AC RETURNED.  INS CHECKED OUT IAW 34-41-00.  HSI/ADI INTERFACE CHECKED ALL INDICATION IS NORMAL W/OUT REMARKS.

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