CHAPTER 4
REFERENCE GUIDE
EFD1000H PFD Pilot’s Guide
Page 4-55
091-00012-001 REV C
For example, suppose you use a GNS-430 to fly a GPS flight plan and have an ILS
instrument approach loaded and active, and the GNS-430 is set for Auto ILS CDI
changeover once you are established inbound on the final approach course. With GPSS
enabled on the PFD and the autopilot in HDG mode, the GPSS will steer the autopilot
laterally through the flight plan using GPS, even after the GNS-430 CDI automatically
switches to VLOC, and the PFD navigation source similarly switches to VLOC. However,
until you switch the autopilot into the Approach mode, it will not arm or capture the
glideslope to fly the ILS approach. This feature is particularly useful for autopilots that
do not automatically transition from Heading mode to Nav mode when the selected
course is intercepted.
When flying an ILS on a WAAS GNS-430W, the autopilot in HDG mode can use the GPSS
to fly the full course reversal automatically, and the GNS-430W will automatically switch
to VLOC once established inbound to the Final Approach Fix. But the pilot must then
engage the Approach mode on the autopilot to track the localizer and couple to the
glideslope.
Several conditions can cause GPSS to be disabled automatically (switching to a different
GPS steering source on the PFD, losing the GPS navigator source, canceling the flight
plan, etc.). If this happens, the PFD will send a Wings Level command to the autopilot
when in HDG mode, the GPSS Hot Key will annunciate the condition by showing
GPSS in inverse amber, and the GPSS# and inverse A annunciation at the top of the
Navigation Display will be shown with a red slash. (
See
Figure 4-112
). To re-engage
GPSS, select a valid GPS navigation source (with valid flight plan or direct-to selection
on the GPS navigator), and then press the GPSS Hot Key. If a valid GPSS signal cannot
be restored, pressing the GPSS Hot Key will cancel GPSS mode and restore the Heading
Bug’s output to the autopilot. More detail on these abnormal conditions, and corrective
pilot actions, can be found in
Chapter 6, Expanded Emergency and Abnormal
Procedures
.
See
also
Chapter 4, Section 4.7.3. Typical Autopilot Operations.
WARNING
It is your responsibility as Pilot in Command to ensure
that you are familiar with the operation of all installed
equipment. Operation of the PFD in IMC conditions
should not be attempted unless you are proficient in its
use and operation, as described herein.
NOTE
Refer to the autopilot systems Aircraft Flight Manual
Supplement and/or POH for details regarding use and
operation of the autopilot system.
Examples here are provided for reference only, based on
operation of the Bendix/King KFC-200 autopilot, and
actual operation may vary depending on the autopilot
system installed in your aircraft.