Garmin G1000 Reference Manual page 91

Vertical Path Tracking descent to VNV Target
Altitude:
1) Select VNV flight control:
a) Press the VNV Key to arm Vertical Path Tracking
Mode. The white annunciation 'VPTH' appears.
b) Using the ALT Knob, set the Selected Altitude
at least 75 feet below the flight plan's VNV
Target Altitude of 10,000 feet.
If the Selected Altitude is not adequately adjusted
below the VNV Target Altitude, the flight director
commands descent to the Selected Altitude rather
than the VNV Target Altitude once Vertical Path
Tracking Mode becomes active (ALTS is armed
rather than ALTV).
c) If Vertical Path Tracking Mode is armed more
than 5 minutes prior to descent path capture,
acknowledgment is required for the flight director
to transition from Altitude Hold to Vertical Path
Tracking Mode. To proceed with descent path
capture if the white 'VPTH' annunciation begins
flashing, do one of the following:
1
TOD
ALT Mode
2
190-00384-09 Rev. A
Cruise Altitude of 12,000 MSL
VNAV Target Altitude of 10,000 MSL
Figure 6-35 VPTH Descent
Garmin G1000 Cockpit Reference Guide for the Cessna Nav III
SECTION 6 – AUTOMATIC
• Turn the ALT Knob to adjust the Selected
Altitude
• Press the VNV Key
If the descent is not confirmed by the time of
interception, Vertical Path Tracking Mode remains
armed and the descent is not captured.
2) When the top of descent (TOD) is reached, the flight
director transitions to Vertical Path Tracking Mode
and begins the descent to the VNV Target Altitude.
Intention to capture the VNV Target Altitude is
indicated by the white 'ALTV' annunciation.
3) As the aircraft nears the VNV Target Altitude, the
flight director transitions to VNV Target Altitude
Capture Mode, indicated by the green 'ALTV'
annunciation flashing for up to 10 seconds.
The green 'ALT' annunciation flashes for up to
10 seconds upon reaching 50 feet from the VNV
Target Altitude; the autopilot transitions to Altitude
Hold Mode and levels the aircraft at the vertical
waypoint.
3
BOD
Selected Altitude (set below VNAV Target Altitude)
Along-track Offset, 3 nm before OPSHN
FLIGHT CONTROL
ALT Mode
3 nm
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