# SDR ASAA2021101136257

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 11, 2021
- Submitted: October 13, 2021
- Operation: Air carrier
- Aircraft: [N471AS](https://openairdocs.org/aircraft/N471AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 41703
- Aircraft time: 26,308 hours, 8,364 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Actuator
- Part number: 158300101
- Part serial: 30351
- Condition: Inoperative
- Location: Auto Pilot
- Part time: 26,322 hours, 8,369 cycles
- Stage of operation: CR
- How discovered: O
- Nature of condition: F
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2021101136257

## Discrepancy

"B" AUTOPILOT WILL NOT ENGAGE A CRUISE. GROUNDED - YES. DFCS FAULT REVIEW SHOWED FAULT 22-11149 "AIL PRESS SW-2" AND DFCS LIBRARY TEST #31 SHOWED CONSISTENT FAIL WITH FAULT 22-11144 "AIL DETENT SOLENOID-2". REMOVED AND REPLACED AUTOPILOT B AILERON ACTUATOR PER B737-900 AMM 22-11-25-000-801/AMM 22-11-25-400-801. REMOVED AND REPLACED AILERON ACTUATOR B PRESSURE SWITCH PER AMM 22-11-40-000-801/AMM 22-11-40-400-801. ACCOMPLISHED AILERON ACTUATOR ADJUSTMENT PER AMM 22-11-25-820-801 AND DFCS LIBRARY TEST #31 PER AMM 22-11-25-710-801 - ALL TESTS PASS.

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