Garmin G1000 NXi Pilot's Manual page 227

Altitudes that have been designated for use in vertical guidance can be "un-designated" using the CLR Key.
The altitude is now displayed only as a reference. It is not used to give vertical guidance. Other displayed
altitudes may change due to re-calculations or be rendered invalid as a result of manually changing an altitude
to a non-designated altitude.
Designating a waypoint altitude to be used for vertical guidance:
1) Press the FPL Key to display the Active Flight Plan Page on the MFD.
2) Press the FMS Knob, and turn to highlight the desired waypoint altitude.
3) Turn the small FMS Knob to enter editing mode.
4) Press the ENT Key. The altitude is now shown in cyan, indicating it is usable for vertical guidance.
Designating a procedure waypoint altitude to be used for vertical guidance:
1) Press the FPL Key to display the Active Flight Plan Page on the MFD.
2) Press the FMS Knob, and highlight the desired waypoint altitude. Turn the small FMS Knob to enter editing
mode. .
3) Press the ENT Key. The altitude is now shown in cyan, indicating it is usable for vertical guidance.
Altitude constraints are displayed and entered in feet mean sea level (MSL) values to the nearest hundred. An
altitude constraint in feet above ground level (AGL) format is supported for airports. When a database altitude
restriction is displayed, the system allows entry of a different altitude when creating a waypoint, effectively
overriding the database restriction (only before the FAF). When a database altitude restriction of type "AT or
ABOVE" or "AT or BELOW" is activated, the system uses the "AT" portion of the restriction to define the vertical
profile.
An altitude constraint is invalid if:
• Meeting the constraint requires the aircraft to climb
• Meeting the constraint requires the maximum flight path angle or maximum vertical speed to be exceeded
• The altitude constraint results in a TOD behind the aircraft present position
• The constraint is within a leg type for which altitude constraints are not supported
• The altitude constraint is added to the FAF of an approach that provides vertical guidance (i.e., ILS or GPS
SBAS approach)
• The altitude constraint is added to a waypoint past the FAF
Entering/modifying an altitude constraint:
1) Press the FPL Key to display the Active Flight Plan Page on the MFD.
2) Press the FMS Knob, and turn to highlight the desired waypoint altitude constraint.
3) Enter an altitude constraint value using the FMS Knobs. To enter altitudes as a flight level, turn the small
FMS Knob counter-clockwise past zero or clockwise past 9 on the first character, and the system automatically
changes to show units of Flight Level. Turn the large FMS Knob clockwise to highlight the first zero and enter
the three digit flight level.
4) Press the ENT Key to accept the altitude constraint; if the selected waypoint is an airport, an additional choice
is displayed. Turn the small FMS Knob to choose 'MSL' or 'AGL', and press the ENT Key to accept the altitude.
190-02177-00 Rev. A
Garmin G1000 NXi Pilot's Guide for Cessna Nav III
FLIGHT MANAGEMENT
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