Narrative:

Approach had the be-30 descend to 4;000 then continue to 2;000. Approaching 2;000 feet I tried to disconnect the autopilot. The autopilot lights went out; but the yoke and trim wheel were still locked. I had the co-pilot pull the ap servo breaker and it took over 20 seconds for the servo to release the yoke and trim. While this was happening we descended to approximately 1;800 feet and ATC advised us of low altitude warning.

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Original NASA ASRS Text

Title: A BE-30 autopilot failed to disengage by the normal means so the Captain had the First Officer pull the autopilot servo circuit breaker which allowed the servo to release 20 seconds or more later.

Narrative: Approach had the BE-30 descend to 4;000 then continue to 2;000. Approaching 2;000 feet I tried to disconnect the autopilot. The autopilot lights went out; but the yoke and trim wheel were still locked. I had the co-pilot pull the AP servo breaker and it took over 20 seconds for the servo to release the yoke and trim. While this was happening we descended to approximately 1;800 feet and ATC advised us of low altitude warning.

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.