# SDR MALA030167

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 22, 2003
- Submitted: February 26, 2003
- Operation: Air carrier
- Aircraft: N457XJ
- Make and model: Saab 340B
- Registry model: [Saab 340B](https://openairdocs.org/model/saab-340b) (OpenAirDocs)
- Aircraft serial: 340B457
- System (JASC): [3420 · Attitude and Direction Data System](https://openairdocs.org/jasc/3420)
- Part: Computer
- Part number: 6226190113
- Part serial: 3045
- Condition: Malfunctioned
- Location: Ahrs
- Stage of operation: NR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/MALA030167

## Discrepancy

DURING FLIGHT NR 2996, CAPT AND F/O'S HEADING OFF 10 DEGREES.  YELLOW HEADING ON EHSI ON ABOUT EVERY 2 MINUTES.  HDG SLAVE RESETS TO ABOUT 5 DEGREE DIFFERENCE.  F/O'S HDG MATCHES MAG COMPASS, CAPTS HDG DRIFTS TO ABOUT +9 DEGREES.  AIR RETURN TO DTW.  MAINTENANCE REPLACED NR 1 AHRS COMPUTER P/N 622-6190-113, SN/OFF 3045, SN/ON 279.  NR 1 AHRS OPS CHECKS GOOD IAW SF340, MM CHAP 34.

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