# SDR ASAA2020120333633

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 3, 2020
- Submitted: December 4, 2020
- Operation: Air carrier
- Aircraft: [N590AS](https://openairdocs.org/aircraft/N590AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35687
- Aircraft time: 47,216 hours, 14,146 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Knob
- Condition: Broken
- Location: Mode Control
- Part time: 17,216 hours, 5,129 cycles
- 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/ASAA2020120333633

## Discrepancy

HEADING KNOB IS BROKEN.  GROUNDED-YES.  REMOVED AND REPLACED MODE CONTROL PANEL B737-800 AMM 21-11-34 / 401.  ACCOMPLISHED MODE CONTROL PANEL TEST, AMM 22-11-34-740-801, TEST PASSED.  REF LP 60146743 FOR CAT 3 AUTOLAND DOWNGRADE DEFERRAL.  PANEL P/N OFF: 822-1567-102 S/N OFF: 46R37NP/N ON: 4082260-939 S/N ON: 97031081.

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