Afcs Operation - Garmin G3X Touch Pilot's Manual

AFCS

9.1 AFCS OPERATION

When a GMC 305 is installed AFCS functionality is distributed across the following
Line Replaceable Units (LRUs):
• GDU 460/465 Display Unit.
• GSU 73/25 ADAHRS Unit
The AFCS system can be divided into these main operating functions:
• Flight Director (FD) — Flight director operation takes place within GDU
460/465. Flight director commands are displayed on the PFD. The flight director
provides:
– Command Bars showing pitch/roll guidance
– Vertical/lateral mode selection and processing
– Autopilot communication
• Autopilot (AP) — Autopilot operation occurs within the pitch, roll, and pitch
servos. It also provides servo monitoring and automatic flight control in response
to flight director steering commands, Air Data and Attitude and Heading Reference
System (ADAHRS) attitude, rate information, and airspeed.
• Yaw Damper (YD) — The yaw servo (optional), is self-monitoring and provides
Dutch roll damping and turn coordination in response to yaw rate, roll angle, lateral
acceleration, and airspeed. If installed the YD comes on when the autopilot is engaged
and stays on after disengaging the autopilot. The YD can be turned on/off independent
of the autopilot using the YD Key.
• Manual Electric Trim (MET) — Manual electric trim may provide trim capability
for any properly configured axis (pitch, roll, or yaw) when the autopilot is not engaged.
212
Garmin G3X Touch Pilot's Guide
• GMC 305 AFCS Mode Control
Unit
• GSA 28 AFCS Pitch/Roll/Yaw
Damper (optional) servos.
190-01754-00 Rev. A