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BendixKing FPI 3501B System FPD 500 User Manual

Page 39

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FPD 500 FLAT PANEL DISPLAY SYSTEM

4. SPECIAL CONSIDERATIONS

4.1 NAVIGATION SOURCE COMBINATIONS

During approach mode (a valid ILS frequency selected), a normal
EADI will display a glideslope scale with pointer and a rising runway.
When displayed, the glideslope pointer position is always determined
by the on-side glideslope receiver. The lateral position of the runway
is always determined by the on-side localizer and the vertical posi-
tion of the runway is always determined by the on-side radio altime-
ter. Cross-side and other sensors are never used, therefore there is
no need to identify these sensor sources. During enroute mode (a
valid ILS frequency is not selected) the glideslope scale and runway
symbol are removed from the EADI display.

The navigation sources used to position the course deviation bar on
the EHSI are identified since three sources are possible. INS is
annunciated as “NAV”, VOR is annunciated as “VOR” and localizer is
annunciated as “ILS”. The glideslope scale with pointer position
determined by the glideslope receiver is also displayed when the
course deviation bar is driven by the localizer receiver and “ILS” is
annunciated as the navigation source. The glideslope scale and
pointer are removed from display on the EHSI when the selected
sensor is “VOR” or “NAV”.

When Integrate mode is selected on an EADI, the navigation source
used to position the course deviation bar on the integrated display will
match that selected for use on the associated EHSI. These naviga-
tion sources are identified with the same annunciations used on the
EHSI.

Some aircraft installations allow independent selection of navigation
sensors for the EADI and EHSI. This can result in unexpected combi-
nations of sensors between the two displays and also on a single
EADI display with the Integrate mode selected. For example, the
presence of a glideslope scale and pointer on an EADI in Integrate
mode does not insure that the course deviation bar on the same dis-
play is driven by the localizer. The actual navigation source of lateral
deviation may be NAV, VOR or ILS as selected for the EHSI. The
correct navigation source is annunciated in all cases and must be
used to avoid confusion. All the possible combinations are shown in
the following figures.

Special Considerations

4-1

Rev. 0
Jan/97

A