# SDR ASAA2017080621554

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 6, 2017
- Submitted: August 8, 2017
- Operation: Air carrier
- Aircraft: [N487AS](https://openairdocs.org/aircraft/N487AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44108
- Aircraft time: 7,121 hours, 2,341 cycles
- System (JASC): [3460 · Flight Management Computing Hardware System](https://openairdocs.org/jasc/3460)
- Part: Fmc
- Condition: Malfunctioned
- Stage of operation: DE
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2017080621554

## Discrepancy

ON DESCENT BOTH FMC SHOWED FMC DISAGREE - VERTICAL IN SCRATCHPAD. FLASHED ABOUT 10 TIMES. NO OTHER FAULTS OR INDICATIONS.  ACFT GROUNDED. INFLIGHT FAULTS OF RIGHT & LEFT FMC SHOW FCC DATA-SYNC ERROR, LAST FLIGHT. PERFORMED FIM 34-61, TASK 837, DUAL SYSTEM ERROR. EVENT IS AN INTERMITTENT FAULT. GROUND VERIFICATION TEST NORMAL.

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