# SDR ASAA2015041211318

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 12, 2015
- Submitted: April 15, 2015
- Operation: Air carrier
- Aircraft: [N459AS](https://openairdocs.org/aircraft/N459AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 36352
- Aircraft time: 4,181 hours, 1,385 cycles
- System (JASC): [3460 · Flight Management Computing Hardware System](https://openairdocs.org/jasc/3460)
- Part: Warning Message
- Condition: False Activation
- Stage of operation: DE
- How discovered: O
- Nature of condition: N
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2015041211318

## Discrepancy

AT 22K FT DESCENDING CAPT SIDE MFD LOST NAV DATA AND SIGNALED VTK LOST DATA ON BOTH CDUS FO MFD HAD FULL NAV DATA LNAV/VNAV DISENGAGED RESTORED NORMAL OPERATION IN 30-40 SECONDS.  ACFT GROUNDED. DFCS BITE LOGGED FMC CHANNEL A FAULT FMC BITE IAW 34-61 TASK 801. SHOWS NO CURRENT FAULTS. NO CURRENT DISCREPANCIES NOTED.

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