# SDR AALA201904229003

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 21, 2019
- Submitted: April 22, 2019
- Operation: Air carrier
- Aircraft: [N929AN](https://openairdocs.org/aircraft/N929AN), registered now
- Make and model: Boeing 737823
- Aircraft serial: 30078
- Aircraft time: 57,210 hours, 23,605 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Computer
- Condition: Faulty
- Location: Nav
- Stage of operation: DE
- 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/AALA201904229003

## Discrepancy

AIRCRAFT WAS GROUNDED: DURING DECENT IN VNAV MODE AIRCRAFT  SUFFERED UNCOMMANDED ELEVATOR INPUTS FROM THE AUTO PILOT.  THESE UNCOMMANDED INPUTS WERE MODERATE, AUTO PILOT CMD - A THE FIRST ONE WAS PASSING 25,000  FEET THE SECOND ONE WAS PASSING 18,000 FEET. ACCOMPLISHED DFCS BITE FAULT HISTORY AND CURRENT FAULTS IAW FIM  22-11-00 ,NO FAULTS FOUND. REMOVED AND REPLACED FCC-A IAW MM 22-11-33.ALL CKS NORMAL  ACCOMPLISHED AND VERIFY IAW MM 22-11-00 AND BITE TEST IAW MM 34-36-00. ALL CKS NORMAL.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.