Cockpit Reference Guide

190-00763-02 Rev. A
Garmin G1000 Pilot’s Guide for the Piper PA-46 Meridian
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AUTOMATIC FLIGHT CONTROL SYSTEM
SYSTEM
OVERVIEW
FLIGHT
INSTRUMENTS
EICAS
AUDIO PANEL
& CNS
FLIGHT
MANAGEMENT
HAZARD
AVOIDANCE
AFCS
ADDITIONAL
FEATURES
APPENDICES INDEX
7.5 AUTOPILOT AND YAW DAMPER OPERATION
NOTE: Refer to the POH for specific instructions regarding emergency procedures.
The Piper PA-46 Meridian autopilot and yaw damper operate the 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 and yaw autotrim provide trim commands to the pitch trim servo and yaw trim
adapter to relieve any sustained effort required by the pitch and yaw servos, respectively. Autopilot operation is
independent of the yaw damper
TheyawdamperreducesDutchrolltendenciesandcoordinatesturns.Itcanoperateindependentlyofthe
autopilotandmaybeusedduringnormalhand-ightmaneuvers.Yawratecommandsarelimitedto6deg/sec
by the yaw damper.
FLIGHT CONTROL
Pitchandrollcommandsareprovidedtotheservosbasedontheactiveightdirectormodes.Yawdamping
is provided by the yaw servo. Servo motor control limits the maximum servo speed and torque. The servo
gearboxes are equipped with slip-clutches set to certain values. This allows the servos to be overridden in case
of an emergency.
PITCH AXIS AND TRIM
The autopilot pitch axis uses pitch rate to stabilize the aircraft pitch attitude during 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 servo. The pitch trim servo commands the motor to reduce the average pitch servo effort.
Whenthe autopilotis notengaged, thepitch trimservo maybe usedto provide manualelectric pitch
trim (MEPT).  This allows the aircraft to be trimmed using a control wheel switch rather than the trim
wheel. Manual trim commands are generated only when both halves of the MEPT Switch are operated
simultaneously. 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 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.
YAW AXIS
The yaw damper uses yaw rate and roll attitude to dampen the aircraft’s natural Dutch roll response.
It also uses lateral acceleration to coordinate turns.  Yaw damper operation is independent of autopilot
engagement.