Garmin GNS 480, Pilot'S Manual

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100
Basic Operation
Points to Remember for Localizer or VOR-based Approaches
• The default factory setting allows the CDI output to automatically switch from the GPS receiver
to the LOC receiver. If the “ILS Autoswitch” setting is changed to “Manual”, you must determine
when to select “GPS” or “VLOC” guidance during the approach. Remember, “LOC” is required for
the final course segment from Final Approach Fix (FAF) to MAP.
• If the CDI output has not automatically switched from GPS to ILS upon reaching the FAF, you
must manually switch to the VLOC receiver by pressing the CDI key. Verify that “LOC” or “VOR”
is displayed directly next to the CDI key.
• Automatic switching of CDI output is available for ILS, localizer, SDF and LDA approaches.
Automatic CDI switching is not available for backcourse approaches or VOR approaches.
• When flying an approach with the autopilot coupled, you must monitor system functions at all
times and verify that the autopilot and external CDI (or HSI) switch to the VLOC receiver with
sufficient time to capture and track the approach course. Switching to “VLOC” late in the ap-
proach may not provide the autopilot enough time to respond and intercept the approach course
prior to the FAF (depending upon the performance characteristics of your autopilot and aircraft).
In such instances, you should manually fly the approach or refer to the documentation provided
with your autopilot.
• When an ILS or VOR approach is first selected or executed, the frequency is automatically
checked, if correct. If the frequency is correct, you will not receive a message regarding the
frequency. If the frequency is incorrect, you will receive a message and you must place the ILS
frequency in the active frequency field by pressing the
Menu/Enter key when the frequency mes-
sage is received.
• When flying a localizer-based approach (other than backcourse) with automatic CDI
switching enabled: