# SDR UIEA200800332

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 15, 2008
- Submitted: October 17, 2008
- Operation: Air carrier
- Aircraft: N523MC
- Make and model: Boeing 747-2D7B
- Registry model: [Boeing 747-2D7B](https://openairdocs.org/model/boeing-747-2d7b) (OpenAirDocs)
- Aircraft serial: 21782
- Aircraft time: 96,852 hours, 19,800 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Autopilot Sys
- Condition: Malfunctioned
- Location: Cockpit
- Stage of operation: CL
- How discovered: O
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UIEA200800332

## Discrepancy

AIR TURNBACK, WHEN A/P "A" IS ENGAGED THE AIRCRAFT STARTED UNCOMMANDED LEFT ROLL.  DISENGAGED "A" A/P. "B" A/P WOULD NOT ENGAGE.  CYCLED YOKE SWITCH NIETHER "A" OR "B" A/P WOULD ENGAGE.  FINALLY GOT "B" TO ENGAGE BUT IT WOULD NOT FOLLOW ANY MODE CONTROL PANEL COMMANDS.  ITEM IS OPEN AS TO THE AIRCRAFT IS ON THE GROUND IN WORK.

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