# SDR ASAA2019031728665

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 17, 2019
- Submitted: March 19, 2019
- Operation: Air carrier
- Aircraft: [N479AS](https://openairdocs.org/aircraft/N479AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 60576
- Aircraft time: 14,719 hours, 4,814 cycles
- System (JASC): [3460 · Flight Management Computing Hardware System](https://openairdocs.org/jasc/3460)
- Part: Fmc
- Condition: Malfunctioned
- Location: Cockpit
- Stage of operation: CR
- 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/ASAA2019031728665

## Discrepancy

LT FMC FAIL W/VTRK ON LT NAV DISPLAY AT CRUISE. TRIED (USING FMC FAIL C/L) TO RESTORE BY PLACING FMC SOURCE SEL SW TO BOTH ON RT. TEMPORARILY RESTORED BUT AFTER SWITCHING TO NML, HAD IMMEDIATE LT FMC FAIL AGAIN. CONTINUED ON SINGLE R FMC. GROUNDED - YES. RE-BOOTED LT FMC - SYS OPS OK. NO HISTORY.

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