# SDR CA070315004

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 12, 2007
- Submitted: May 1, 2007
- Operation: General aviation
- Make and model: Aerosp ATR 42-300
- Registry model: [Aerosp ATR 42-300](https://openairdocs.org/model/aerospatiale-aeritalia-atr-42-300) (OpenAirDocs)
- Aircraft time: 28,396 hours
- Engine: Pwa PW120
- System (JASC): [3410 · Flight Environment Data](https://openairdocs.org/jasc/3410)
- Part: Hsi
- Part number: 7004544713
- Part serial: 7004544713
- Condition: Malfunctioned
- Location: Nr 1
- Stage of operation: CL
- How discovered: O
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CA070315004

## Discrepancy

(CAN) DEPARTING THE CREW OBSERVED A CIRCUIT BREAKER TRIP ON THE NR 1 EADI, RESET SUCCESSFUL. THIS WAS FOLLOWED BY A CIRCUIT BREAKER TRIP ON THE NR 1 EHSI. THE RESET ATTEMPT FAILED AND THE AIRCRAFT RETURNED TO POINT OF DEPARTURE WITHOUT FURTHER PROBLEM. MAINTENANCE REPLACED THE NR 1 SYMBOL GENERATOR UNIT.  THE SYSTEM FUNCTION CHECKED SATISFACTORY AND THE AIRCRAFT WAS RETURNED TO SERVICE. (TC NR 20070315004)

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