User Guide

190-00552-00 Rev. A Garmin G1000 Pilot’s Guide for the Columbia 350/400 7-19
AUTOMATIC FLIGHT CONTROL SYSTEM
7.4 AUTOPILOT OPERATION
The Columbia 350/400’s autopilot operates flight control surface servos to provide automatic flight control.
The autopilot controls the aircraft pitch and roll attitudes following commands received from the flight director.
Pitch autotrim provides trim commands to the pitch trim adapter to relieve any sustained effort required by the
pitch servo.
FLIGHT CONTROL
Pitch and roll commands are provided to the GSA 81 servos, based on the active flight director modes. Servo
motor control limits the maximum servo speed and torque.
PITCH AXIS AND PITCH TRIM
The autopilot pitch axis uses pitch rate to stabilize the aircraft pitch attitude during upsets and flight
director maneuvers. Flight director pitch commands are rate- and attitude-limited, combined with pitch
damper control, and sent to the pitch servo motor. The pitch servo measures the output effort (torque) and
provides this signal to the pitch trim adapter. The pitch trim adapter commands the motor to reduce the
average pitch servo effort.
When the autopilot is not engaged, the pitch trim adapter may be used to provide manual electric trim.
This allows the aircraft to be trimmed using a control stick switch rather than the trim wheel. Manual trim
commands are generated with the
MET Switch. Trim speeds are scheduled with airspeed to provide more
consistent response.
ROLL AXIS
The autopilot roll axis uses roll rate to stabilize aircraft roll attitude during upsets and flight director
maneuvers. The flight director roll commands are rate- and attitude-limited, combined with roll damper
control, and sent to the roll servo motor.
EMERGENCY CONTROL OVERRIDE
NOTE: Refer to the AFM for specific instructions regarding emergency procedures.
The GSM 85 servo mounts are equipped with slip-clutches set to certain values. This allows the servos to
be overridden in case of an emergency.