# SDR ASAA2021062035159

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 20, 2021
- Submitted: July 7, 2021
- Operation: Air carrier
- Aircraft: [N518AS](https://openairdocs.org/aircraft/N518AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35693
- Aircraft time: 45,115 hours, 13,337 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Sensor
- Part number: H504B
- Part serial: D7808
- Condition: Faulted
- Location: Aileron Position
- Part time: 59,357 hours, 23,732 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/ASAA2021062035159

## Discrepancy

UNABLE TO COMPLETE TC 782223000 FLIGHT MANAGEMENT SYSTEM AND NAVIGATION FUNCTION CHECK, DUE TO FAILURE OF DFCS BITE LIBRARY NUMBER 60.31 AUTO PILOT B AILERON SENSOR 2 FAULT MSG 22-11146 (J18-K13) AND (J1B-H13) AND MSG 22-11340 R AILERON SENSOR EXC INV.  GROUNDED - YES. REMOVED AND REPLACED AILERON POS SENSOR. FAILS LRU REPLACEMENT TEST. FOUND R/H AILERON IS OUT OF RIG, CONTROL SURFACE IS TOO LOW REF B737-800 AMM 27-11-00-820-805 STEP 6.F.(1)(R). ADJUSTED R/H AILERON WING CABLES ABSA & ABSB REF AMM 27-11-00-820-801. AILERON SENSOR TEST PASSED REF AMM 22-11-29. ACCOMPLISHED ROLL POS SENSOR TEST REF AMM 22-11-29, TEST PASSED. LAND VERIFY TEST PASSED. AUTOPILOT B OPS TEST PASSED REF AMM 22-11-00.

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