# SDR ASAA2017052120843

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 21, 2017
- Submitted: May 23, 2017
- Operation: Air carrier
- Aircraft: [N531AS](https://openairdocs.org/aircraft/N531AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35199
- Aircraft time: 27,267 hours, 8,102 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Unknown
- Condition: Malfunctioned
- Location: Autopilot Sys
- Stage of operation: NR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2017052120843

## Discrepancy

VERTICAL SPEED FUNCTION OF MCP INOP WHEN A AUTOPILOT IS ENGAGED. ALL OTHER MCP FUNCTIONS OPERATE NORMALLY WITH A AUTOPILOT ENGAGED. ALL FUNCTIONS OPERATE NORMALLY WITH B AUTOPILOT ENGAGED. GROUNDED - YES. PERFORMED DFCS MODE CONTROL PANEL TEST. FOUND NO CURRENT FAULTS. ETOPS GROUND VERIFICATION SUCCESSFUL, REF B737-800 FIM 22-11 TASK 803.

---
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.