Pilot's Guide

190-00663-02 Rev. B
Garmin G1000 Pilot’s Guide for the Hawker Beechcraft C90A/GT/GTi
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AUTOMATIC FLIGHT CONTROL SYSTEM
7.5 AUTOPILOT AND YAW DAMPER OPERATION
NOTE: Refer to the POH/AFM for specific instructions regarding emergency procedures.
The 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ightdirector.Pitch
autotrim provides trim commands to the pitch trim servo to relieve any sustained effort required by the pitch
servo. 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
mounts 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ight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ight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.