TM 1-1510-223-10
3-30
Table 3-2. Comparison Monitor Symbols and Miscompare Levels
Compared Signals
Displayed
Miscompare Level
Compared Signals
Symbol
Miscompare Level
1. Pitch Attitude
PIT
6
2. Roll Attitude
ROL
6
** 3. Heading
HDG
6
* 4. Localizer
LOC
40 mV ( 1/2 dot)
* 5. Glideslope
GS
50 mV ( 1 dot)
6. Pitch & Roll Attitude
ATT
50 mV
* 7. Localizer & Glideslope
ILS
50 mV ( 1 dot)
* These comparisons are only active during flight director localizer and glideslope capture with both NAV
receivers tuned to LOC frequency.
** If the compared heading sources are not the same (both MAG or TRU), the comparison monitor is disable.
Figure 3-11. EADI Failure Annunciations (Red)
(6) Double-needle bearing pointer. The double-
needle bearing pointer (green diamond) indicates the
relative bearing to the selected navaid. The navigation
source is indicated by the double-needle pointer source
annunciator. When the bearing pointer navigation source
is invalid or a localizer frequency has been chosen, the
bearing pointer will be removed from the display.
(7) DME hold annunciator. Illumination of the am-
ber DME hold (H) annunciator indicates that hold has
been selected on the VOR navigation receiver control
panel that is supplying navigation information to the re-
spective EHSI.
(8) Navigation source annunciator. The naviga-
tion source that is being used by the EHSI is indicated by
the illumination of a navigation source annunciator. Pos-
sible annunciations are VOR1, VOR2, ILS1, ILS2, TCN,
and INS. All the annunciations are white, except INS
which is annunciated in blue to show that it is a long range
navigation system. The navigation source will annunci-
ate amber if the pilot and copilot select the same naviga-
tion source. The navigation source will annunciate amber
if the pilot has selected VOR2 or if the copilot has se-
lected VOR1.
