User Guide

190-00552-00 Rev. A Garmin G1000 Pilot’s Guide for the Columbia 350/400 7-9
AUTOMATIC FLIGHT CONTROL SYSTEM
ALTITUDE HOLD MODE (ALT)
Altitude Hold Mode is engaged by pressing the ALT Key; the mode is indicated by an ‘ALT’ annunciation in
the AFCS Status Box. In this mode, the flight director establishes and maintains the current aircraft altitude
as the Altitude Reference. The flight director’s Altitude Reference is shown in the AFCS Status Box and is
independent of the Selected Altitude, displayed above the Altimeter.
CHANGING THE ALTITUDE REFERENCE
NOTE: Rotating the ALT Knob while in Altitude Hold Mode changes the Selected Altitude, but not the flight
director’s Altitude Reference.
With the CWS Button depressed, the aircraft can be hand-flown to a new Altitude Reference. When the
CWS Button is released at the desired altitude, the new altitude is established as the Altitude Reference.
If the Selected Altitude is captured during CWS maneuvering, the Altitude Reference is not changed. To
adjust the Altitude Reference in this case, the
CWS Button must be pressed again after the Selected Altitude
is captured.
ALTITUDE ARM/CAPTURE
Altitude Hold Mode is armed automatically when the flight director is in Pitch Hold, Vertical Speed,
Flight Level Change, or Go Around Mode. This is indicated by a white annunciation ‘ALT’ in the armed
pitch mode field. When armed, the flight director commands a constant acceleration maneuver to capture
and level off at the Selected Altitude. When the flight director starts the altitude capture, it transitions to
Altitude Hold Mode and holds the Selected Altitude; in this case, the Altitude Reference corresponds to the
Selected Altitude. The white ‘ALT’ annunciation moves to the active pitch mode field and flashes green for
ten seconds to indicate transition to Altitude Hold Mode.
Figure 7-6 Altitude Hold Mode
Altitude Hold
Mode Active
Flight Director
Altitude Reference
Selected Altitude
Selected Altitude Bug
Command Bars
Hold Pitch Attitude
to Maintain Altitude
Reference