User guide

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 two sources are possible. INS is annun-

ciated as “INS”, and VOR or Localizer is annunciated as “RAD”. 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. The glideslope scale and pointer are removed

from display on the EHSI when the selected sensor is a VOR or INS.

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.

Aircraft installations must not allow independent selection of naviga-

tion sensors for the EADI and EHSI. This could result in unexpected

combinations of sensors between the two displays and also on a sin-

gle EADI display with the Integrate mode selected. For example, the

installation must not allow ILS and INS to both be selected at the

same time. For installations that comply, the presence of a glideslope

scale and pointer on an EADI in Integrate mode will insure that the

course deviation bar on the same display is driven by the localizer.

The only combinations of ILS (approach mode), RAD, and INS selec-

tions that should be allowed are shown in the following figures.

Special Considerations

4-1

Rev. 0

Dec/97