# SDR 9WGA2023053054502

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 30, 2023
- Submitted: June 2, 2023
- Operation: Air carrier
- Aircraft: [N545JN](https://openairdocs.org/aircraft/N545JN), registered now
- Make and model: Doug MD-11F
- Registry model: [Doug MD-11F](https://openairdocs.org/model/mcdonnell-douglas-md-11f) (OpenAirDocs)
- Aircraft serial: 48545
- Aircraft time: 90,140 hours, 16,748 cycles
- System (JASC): [3400 · Navigation System](https://openairdocs.org/jasc/3400)
- Part: Control Unit
- Part number: 4059060901
- Part serial: 94050629
- Condition: Inoperative
- Stage of operation: TO
- How discovered: V
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/9WGA2023053054502

## Discrepancy

AIR RETURN DUE TO UNRELIABLE AIRSPEED. SWITCHING CADC SIDE TO 2, OPS NORMAL.  R & R CADC #1 IAW AMM 34-16-01. PERFORM LEAK CHECK ON #1 SYSTEM IAW AMM 34-11-00-700-801. OPS CHECK NORMAL, NO FAULTS NOTED AT THIS TIME.

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