B757 flight crew experiences an MCP failure at FL400 resulting in erratic autopilot and autothrust o...

Attributes
ACN	1112546
Time
Date	201308
Local Time Of Day	1801-2400
Place
Locale Reference	ZDV.ARTCC
State Reference	CO
Aircraft 1
Make Model Name	B757 Undifferentiated or Other Model
Component
Aircraft Component	MCP
Person 1
Function	First Officer
Experience	Flight Crew Last 90 Days 180 Flight Crew Total 14000 Flight Crew Type 3500
Person 2
Function	Captain Pilot Flying
Experience	Flight Crew Last 90 Days 240 Flight Crew Total 18300 Flight Crew Type 12600
Events
Anomaly	Aircraft Equipment Problem Critical

Narrative:

At FL400; all lights on MCP flashed and autopilot and autothrottle kicked off. Aircraft dipped and rolled right. MCP completely failed and autopilot and autothrottle continued to cycle on and off. Every time they cycled; aircraft would roll and pitch to grab whatever MCP thought was in it. Declared an emergency; diverted to ZZZ with no pitch trim. Rest of flight uneventful besides having to muscle aircraft a bit.

Original NASA ASRS Text

Title: B757 flight crew experiences an MCP failure at FL400 resulting in erratic autopilot and autothrust operation and failure of the horizontal stabilizer trim. Flight diverts to the nearest suitable airport.

Narrative: At FL400; all lights on MCP flashed and autopilot and autothrottle kicked off. Aircraft dipped and rolled right. MCP completely failed and autopilot and autothrottle continued to cycle on and off. Every time they cycled; aircraft would roll and pitch to grab whatever MCP thought was in it. Declared an emergency; diverted to ZZZ with no pitch trim. Rest of flight uneventful besides having to muscle aircraft a bit.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.