# SDR ASAA2018123177618

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 27, 2018
- Submitted: December 31, 2018
- Operation: Air carrier
- Aircraft: [N435AS](https://openairdocs.org/aircraft/N435AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 43292
- Aircraft time: 20,840 hours, 6,848 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: P
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2018123177618

## Discrepancy

BOTH FMC'S FAILED DURING DESCENT. VTK DISPLAYED ON CAPT'S DISPLAY. NORMAL OPS RESTORED AFTER ABOUT 30 SECONDS. QRC PROCEDURE WAS NOT USED. GROUNDED - YES. FMC R LOGGED FMC-L PRES POS LAT RATE FAULT LEG 1 & FMC LEFT & RIGHT LOGGED CDU-R GRD FAULT. COMPLETED B737-900 FIM 34-21 TASK 801, ADIRS BITE, NO FAULTS NOTED. COMPLETED FIM 34-61 TASK 824, ADIRS FAULT ISOLATION. COMPLETED FIM 34-61 TASK 804, CONTROL DISPLAY UNIT BLANKS, NO FAULTS NOTED. COMPLETED FIM 34-61 TASK 801 FMC BITE #1 & #2 FMC NO FAULTS NOTED.

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