Narrative:

I was climbing to my assigned altitude of 10;000; to expect 15;000 ft. As I was passing through 9;600 I applied left roll trim; at which point the heading servo of the autopilot disconnected abruptly; the aircraft rolled to a bank angle of 30 degrees to the left and started a left turn. Simultaneously; the altitude servo on the autopilot disconnected and the aircraft abruptly climbed.the autopilot servos on the dynon system are designed to be overridden at 32 psi. During autopilot operation; and while engaged; the pfd (primary flight display) will display either a yellow cautionary advisory to adjust the altitude or heading trim to decrease the load [on] the autopilot [servos]. In this situation I can only surmise that the application of the roll trim (the yellow caution warning on the autopilot displayed 'slip' simultaneously with the disconnect) placed additional pressure on the heading servo; exceeding the 32 psi; and causing a disconnect; which then caused the altitude hold servo to disconnect as well. While arresting the bank angle; heading; and altitude deviations; I noted an altimeter readout of 11;100. Upon getting the aircraft restabilized; approach queried the deviation and I explained in abbreviated terms; apologized and stated that I had 'been busy'. I was then handed off to center and subsequentially instructed to climb to 15;000 ft. The turbine legend is a relatively high performance aircraft with a high wing loading and is extremely responsive to control input. By the autopilot apparently being overridden; the aircraft responded to prior; established; trim settings.

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Original NASA ASRS Text

Title: As he was climbing to his cleared altitude of 10;000 MSL on autopilot; the pilot of a Turbine Legend Experimental aircraft was adjusting the aileron trim when the autopilot pitch and roll servos disconnected and the aircraft abruptly climbed to 11;100; rolled into a 30 degree left bank turn. The pilot recovered control and returned to his clearance.

Narrative: I was climbing to my assigned altitude of 10;000; to expect 15;000 FT. As I was passing through 9;600 I applied left roll trim; at which point the heading servo of the autopilot disconnected abruptly; the aircraft rolled to a bank angle of 30 degrees to the left and started a left turn. Simultaneously; the altitude servo on the autopilot disconnected and the aircraft abruptly climbed.The autopilot servos on the Dynon System are designed to be overridden at 32 PSI. During autopilot operation; and while engaged; the PFD (Primary Flight Display) will display either a yellow cautionary advisory to adjust the altitude or heading trim to decrease the load [on] the autopilot [servos]. In this situation I can only surmise that the application of the roll trim (the yellow caution warning on the autopilot displayed 'slip' simultaneously with the disconnect) placed additional pressure on the heading servo; exceeding the 32 PSI; and causing a disconnect; which then caused the altitude hold servo to disconnect as well. While arresting the bank angle; heading; and altitude deviations; I noted an altimeter readout of 11;100. Upon getting the aircraft restabilized; Approach queried the deviation and I explained in abbreviated terms; apologized and stated that I had 'been busy'. I was then handed off to Center and subsequentially instructed to climb to 15;000 FT. The Turbine Legend is a relatively high performance aircraft with a high wing loading and is extremely responsive to control input. By the autopilot apparently being overridden; the aircraft responded to prior; established; trim settings.

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.