# SDR ASAA2023010741439

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 7, 2023
- Submitted: January 9, 2023
- Operation: Air carrier
- Aircraft: [N442AS](https://openairdocs.org/aircraft/N442AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 43293
- Aircraft time: 33,824 hours, 10,705 cycles
- System (JASC): [2200 · Auto Flight System](https://openairdocs.org/jasc/2200)
- Part: Unknown
- Condition: Unknown
- Location: Unknown
- Stage of operation: NR
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2023010741439

## Discrepancy

ON DEP, HDG BUG WAS STUCK ON RWY HDG. UNSELECTABLE IN HDG MODE OR IN LNAV. F/D HDG MODE WAS NOT WORKING. APPROX 5 MINS LATER, HDG WAS AGAIN SELECTABLE. F/D HDG MODE AVAILABLE. NO FURTHER ISSUES. GROUNDED - YES. ACCOMPLISHED B737-900 FIM 22-11 TASK 803. OPS TEST NORMAL REF MCP LRU TEST REF B737-900 AMM 22-11-00-740-801.

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