Aspen Avionics Evolution EFD 1000 C3 Pro PFD - Course Pointer and; Horizontal Situation Indicator (HSI)

CHAPTER 2 CONTROLS AND DISPLAY
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091-00019-001 REV B
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091-00019-001 REV BEFD1000 C3 Pro PFD Pilot’s Guide
2.3.4.2. Horizontal Situation Indicator (HSI)
The traditional HSI is an instrument that combines a slaved magnetic Heading Indicator
overlaid with a rotating Course Pointer and Course Deviation Indicator (CDI). This combination
helps the pilot better visualize the aircraft position relative to the desired course. The HSI is a
vast improvement over the older, separate Directional Gyro (DG) and OBS course deviation
indicator, because the compass heading is always correct (slaved to a remote magnetic ux
detector), and the integration of the CDI onto the compass simplies the instrument scan
and provides better situational awareness.
Pilots experienced with a mechanical HSI will nd the PFD’s 360º Compass Mode immediately
familiar. In its basic form, it is just an electronic representation of a mechanical HSI. Pilots
transitioning from ying a DG and OBS should seek dual instruction from a CFII on the
dierences in ying an HSI.
2.3.4.3. Course Pointer and Course Deviation Indicator (CDI) Bar
In the 360º Compass Mode, the Course Pointer and CDI resemble those of a mechanical
HSI, with an arrowhead pointing to the selected course, and a movable center bar
indicating course deviation against a scale of two dots to either side of the center. A
TO/FROM indication is shown as a triangle above (TO) or below (FROM) the ends of the
Course Deviation Indicator bar.
The ARC Compass Mode has two dierent CDI formats —ARC HSI Mode and ARC CDI Mode.
The ARC HSI Mode, presents a full rotating Course Pointer with CDI, which resembles that
used in the HSI in the 360° Compass Mode. The ARC CDI Mode presents a short Course
Pointer stub on the compass arc and a xed CDI at the bottom of the display, similar to the
LDI and resembling that used in contemporary GPS navigation displays. The ARC CDI Mode
allows more open space for ight plan and basemap details. A TO indication is shown to the
left of the xed CDI, and a FROM indication is shown to its right.