# SDR ASAA2021090435862

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 4, 2021
- Submitted: September 22, 2021
- Operation: Air carrier
- Aircraft: [N459AS](https://openairdocs.org/aircraft/N459AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 36352
- Aircraft time: 27,864 hours, 8,905 cycles
- System (JASC): [3460 · Flight Management Computing Hardware System](https://openairdocs.org/jasc/3460)
- Part: Computer
- Part number: 1714970501
- Part serial: 0000493
- Condition: Failed
- Location: E/E Bay
- Part time: 70,402 hours, 33,006 cycles
- Stage of operation: IN
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2021090435862

## Discrepancy

WHILE ACCOMPLISHING T/C (N8234000 FMC NAV DATA UPDATE) FAILED LOAD. MESSAGE: DATA LOAD IN-OP, NDB MEMORY FAIL. WOULD NOT CROSSLOAD BACK TO #1 AFTER FAILED ATTEMPTS. GROUNDED - YES. REMOVED AND REPLACED #1 FMCS COMPUTER REF B737-900 AMM 34-61-02. ALL TEST PASS. GROUND VERIFICATION TEST SUCCESSFUL.

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