Pilot's Guide

Garmin G1000 Pilot’s Guide for the Beechcraft C90A/GT/GTi
190-00663-03 Rev. A
446
AUTOMATIC FLIGHT CONTROL SYSTEM
DISENGAGEMENT
The autopilot is manually disengaged by pushing the AP Key on the AFCS Control Unit, or the MEPT ARM
Switch. Manual autopilot disengagement is indicated by a five-second flashing yellow ‘AP’ annunciation and a
three-second autopilot disconnect aural alert.
Figure 7-38 Manual Autopilot Disengagement
Pushing the AP/YD DISC Switch or YD Key disengages both the yaw damper and the autopilot. When the
yaw damper and autopilot are manually disengaged, both the ‘AP’ and ‘YD’ annunciation turn yellow and flash
for 5 seconds and a three-second autopilot disconnect aural alert is generated.
Figure 7-39 Yaw Damper Disengagement
After manual disengagement, the autopilot disconnect aural alert may be cancelled by pushing the MEPT ARM
or AP/YD DISC Switch ( AP/YD DISC Switch also cancels the flashing ‘AP’ annunciation).
Automatic autopilot disengagement is indicated by a flashing red and white ‘AP’ annunciation and by the
autopilot disconnect aural alert, which continue until acknowledged by pushing the AP/YD DISC or MEPT ARM
Switch. Automatic autopilot disengagement occurs due to:
• System failure
• Invalid sensor data
• Inability to compute default flight director modes (FD also disengages automatically)
Yaw damper disengagement is indicated by a five-second flashing yellow ‘YD’ annunciation. Automatic yaw
damper disengagement occurs when autopilot disengagement is caused by failure in a parameter also affecting
the yaw damper. This means the yaw damper can remain operational in some cases where the autopilot
automatically disengages. A localized failure in the yaw damper system or invalid sensor data also cause yaw
damper disengagement.
Figure 7-40 Automatic Autopilot and Yaw Damper Disengagement