Points To Remember For Localizer Or Vor-Based Approaches - Garmin GNS 400W Pilot's Manual & Reference

5 - PROCEDURES
Points to Remember
If ATC directs you to make a change, recheck each
element again.
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. This may be changed to manual
in some installations. If the "ILS CDI Selection" set-
ting is changed to "Manual", you must determine
when to select "GPS" or "VLOC" guidance during
the approach. Remember, "VLOC" is required for
the final course segment from Final Approach Fix
(FAF) to MAP.
NOTE: Installations with certain autopilots, such
as the KAP 140 and KFC225, do not allow auto-
matic ILS CDI switching.
NOTE: GPS level of service annunciations (LPV,
ENR, etc.) are not applicable to the external CDI
(or HSI) when VLOC is active.
• 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 "VLOC" is displayed directly
above to the CDI key.
• Automatic switching of CDI output is available
for ILS, localizer, SDF and LDA approaches. Auto-
matic 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
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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 approach 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 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 or VLOC frequency in the active
frequency field.
• When flying a localizer-based approach
(other than backcourse) with automatic CDI
switching enabled:
1. "GPS" guidance may be used while flying
outbound and on the initial portion of the
procedure turn.
2. "VLOC" guidance is used on the remainder of
the approach from the time you turn inbound
on the procedure turn.
3. The localizer frequency must be active to use
"VLOC" guidance at the MAP. Press the CDI
key to switch back to GPS data when the
missed approach is initiated.
190-00356-00 Rev G