Figure 3-17. EHSI Multiple Waypoint Map Mode (LRN)
Each waypoint will be identified by a number between
00 and 09.
The waypoint to which the aircraft is flying will be
magenta, with all other waypoints in white.
If the EFIS is receiving valid TACAN, VOR
information, and DME distance, the navaids for the two
VOR or TACAN stations will be available for display on
the EFIS. The blue navaid will be VORI (NAV1) and the
green navaid will be VOR2 (NAV2).
The EHSI can display up to six LRN waypoints and
two VOR station navaid symbols at the same time. This
assumes that all waypoints are within the selected
weather radar range, and all are within the limits of the
heading display of the EHSI in the map mode.
The specific functions of the multiple-waypoint map
mode are as follows:
(1) Desired track. The desired track annunciator
and a digital readout of the desired track from past
waypoint to the next waypoint are shown in the upper left
corner of the EHSL
(2) To from annunciator. The to-from display is
located to the right of the desired track digital readout It
shows TO when the aircraft is flying to the waypoint
EHSI Weather Radar Displays.
(1) Target alert annunciator (all formats). When
target alert is selected on the weather radar controller,
TGT in green is displayed on the EHSI. If a level 3
weather radar return is detected within 7.5 degrees of
aircraft heading, but beyond the selected radar range, the
annunciator will change TGT to amber.
(2) Range ring and annunciator. The range ring
and annunciator is displayed only when WX, NAV, and
NAV/WX format is selected. The range is selected on the
weather radar controller. One-half the selected range is
annunciated in white beside the half range ring. If
weather radar range control is not available, the range
default value will be 50 nautical miles.
(3) Weather radar modes. Weather radar mode
is annunciated on the EHSI.
(4) Weather radar return display. Weather radar
(WX) mode, weather radar information is displayed (table
(5) Lightning sensor system display. Three
levels of lightning activity are displayed using a white
lightning symbol. A magenta lightning symbol is used to
annunciate activity at an unknown range.