# SDR ASAA2023021841982

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 18, 2023
- Submitted: February 20, 2023
- Operation: Air carrier
- Aircraft: [N478AS](https://openairdocs.org/aircraft/N478AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44105
- Aircraft time: 28,188 hours, 8,914 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Unknown
- Part number: UNKNOWN
- Condition: Unknown
- Location: Unknown
- Stage of operation: AP
- How discovered: V
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2023021841982

## Discrepancy

ON APPROACH FO'S FLIGHT DIRECTOR LATERAL DEVIATION BAR DISAPPEARED AFTER LOC CAPTURE, THEN AFTER G/S CAPTURE LOST VERTICAL FLIGHT DIRECTOR BAR AS WELL AND A/P DISENGAGED. HAD BOTH A/P'S ENGAGED FOR CIII/AUTOLAND APPROACH AT THE TIME. GROUNDED - YES. FOUND FAULT 'R F/D COMP' MSG 22-11486 ON 2/18/23 IN DFCS BITE. PER B737-900 FIM 22-14 TASK 801 AND B737-900 AMM 22-00-01, FOUND TO BE INTERMITTENT FAULT.

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