Suspected Autopilot Malfunction; Overpowering Autopilot Servos - Garmin Beechcraft 200 Series Cockpit Reference Manual

Abnormal Operation

SUSPECTED AUTOPILOT MALFUNCTION

NOTE: Consult the aircraft documentation for the location of circuit breakers
as well as specifics that may supplement or amplify this procedure.
If an autopilot failure or trim failure is suspected to have occurred, perform the
following steps:
1) Firmly grasp the control wheel.
2) Press and hold the AP/YD DISC Switch. The autopilot will disconnect and
power is removed from the trim motor. Power is also removed from all
primary servo motors and engaged solenoids. Note the visual and aural
alerting indicating autopilot disconnect.
3) Retrim the aircraft as needed. Substantial trim adjustment may be needed.
4) Pull the appropriate circuit breaker(s) to electrically isolate the servo and
solenoid components.
5) Release the AP/YD DISC Switch.

OVERPOWERING AUTOPILOT SERVOS

In the context of this discussion, "overpowering" refers to any pressure or force applied
to the pitch controls when the autopilot is engaged. A small amount of pressure or force
on the pitch controls can cause the autopilot automatic trim to run to an out-of-trim
condition. Therefore, any application of pressure or force to the controls should be
avoided when the autopilot is engaged.
Overpowering the autopilot during flight will cause the autopilot' s automatic trim to
run, resulting in an out-of-trim condition or cause the trim to hit the stop if the action
is prolonged. In this case, larger than anticipated control forces are required after the
autopilot is disengaged.
The following steps should be added to the preflight check:
1) Check for proper autopilot operation and ensure the autopilot can be
overpowered.
2) Note the forces required to overpower the autopilot servo clutches.
176 176 Garmin G1000 NXi Cockpit Reference Guide for the Beechcraft 200/B200 Series
190-02040-01 Rev. B