Cockpit Reference Guide

Garmin G1000 Cockpit Reference Guide for the Cessna Nav III
190-00384-08 Rev. A
SECTION 6 – AUTOMATIC
FLIGHT CONTROL
6-20
When the CDI has automatically switched from GPS to
LOC during a LOC/ILS approach, GPS Navigation Mode
remains active, providing GPS steering guidance until
the localizer signal is captured. LOC Navigation Mode is
armed in anticipation of localizer signal capture if the APR
Key is not pressed prior to the automatic source switch.
If Navigation Mode is active and either of the following
occur, the flight director reverts to Roll Hold Mode (wings
rolled level):
• Different VOR is tuned while in VOR Navigation
Mode (VOR Navigation Mode reverts to armed)
• Navigation source is manually switched
• Localizer signal is not captured by the final approach
fix (FAF) while in LOC Navigation Mode
Changing the Selected Course
The Selected Course on the PFD is controlled using the
CRS Knob. Pressing the CWS Button and hand-flying
the aircraft does not change the Selected Course while in
Navigation Mode. The autopilot guides the aircraft back
to the Selected Course (or GPS flight plan) when the CWS
Button is released.
Approach Mode (GPS, VAPP, LOC)
NOTE: The selected navigation receiver must have
a valid VOR or LOC signal or active GPS course
for the flight director to enter Approach Mode.
Approach Mode is activated when the APR Key is
pressed. Approach Mode acquires and tracks the selected
navigation receiver on the HSI (GPS, VOR, or LOC),
depending on the loaded approach. This mode uses the
selected navigation receiver deviation and desired course
inputs to fly the approach. Approach Mode provides
greater sensitivity for signal tracking than Navigation
Mode.
Pressing the APR Key when the CDI is greater than
one dot arms the selected approach mode (annunciated
in white to the left of the active roll mode). If the selected
navigation receiver is GPS, pressing the
APR Key arms
GPS Approach Mode, provided that a GPS approach has
been loaded into the flight plan. If the loaded approach
provides WAAS-based vertical guidance, Glidepath Mode
is also armed (Figure 6-16). If GPS Approach Mode is
selected while in GPS Navigation Mode, capture can occur
with crosstrack error of up to 2 nm.
Figure 6-24 GPS Approach Mode Armed
LOC Approach Mode allows the autopilot to fly a LOC/
ILS approach with a glideslope. LOC Approach Mode is
armed (along with Glideslope Mode; see Figure 6-17)
when the APR Key is pressed and either of the following
have been done:
• Navigation source is set to LOC
• A LOC/ILS approach is loaded into the flight plan
and the corresponding localizer frequency tuned
(even if the selected navigation source is GPS)
Localizer capture is suppressed until the navigation
source is changed to LOC.
If Approach Mode is active and either of the following
occur, the flight director reverts to Roll Hold Mode (wings
rolled level):
• Vectors-to-Final is activated
• Navigation source is manually switched
• Localizer signal is not captured by the final approach
fix (FAF) while in LOC Navigation Mode
Changing the Selected Course
The Selected Course on the PFD is controlled using the
CRS Knob. Pressing the CWS Button and hand-flying
the aircraft does not change the Selected Course while in
Approach Mode. The autopilot guides the aircraft back to
the Selected Course (or GPS flight plan) when the CWS
Button is released.