# SDR ASAA2021042134628

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 21, 2021
- Submitted: April 23, 2021
- Operation: Air carrier
- Aircraft: [N519AS](https://openairdocs.org/aircraft/N519AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 36482
- Aircraft time: 44,436 hours, 13,130 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Actuator
- Part number: 158300101
- Part serial: 20957
- Condition: Faulted
- Location: Autopilot Sys
- Part time: 44,431 hours, 13,123 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/ASAA2021042134628

## Discrepancy

DURING ELEV FEEL COMP TEST - FAILED ELEV DUAL AUTHORITY TEST 51.27 - B CHANNEL OUT OF LIMITS. GROUNDED - YES. DID TEST OF "B" ELEV A/P ACT REF B737-800 AMM 22-11-26-820-801. A AND B WITHIN LIMITS AT 2.01. THEN RAN DUAL AUTHORITY TEST REF AMM 22-11-00-820-816 - STILL FAILS 51.27 TEST A -2.10 AND B -1.91. SUSPECT BAD "B" ELE A/P ACTUATOR. REMOVED AUTOPILOT ELEVATOR ACTUATOR "B" REF AMM 22-11-26-000-801 AND AMM 27-31-00-800-802. INSTALLED NEW "B" AUTOPILOT ACTUATOR. LEAK CHECK OK. REF AMM 27-31-00-840-802, AMM 22-11-26-400-801. COMPLETED ALL TESTING OF THE B CHANNEL ELEVATOR A/P ACTUATOR PER AMM 22-11-26/401. ALL TESTS NORMAL. TEST 51.27 NOW PASSES.

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