annunciator. The compass synchronization annunciator
consists of a dot and X symbol display. When the
compass system is in the slaved mode, the display will
oscillate between the dot and X symbol, indicating the
heading dial is synchronized with a gyro stabilized
Course deviation dots. In VOR or
TACAN operation, each dot represents 5 degree
deviation from the centerline (10 degrees). In ILS
operation, each dot represents 1 degree deviation from
the centerline. In INS operation, each dot represents 3.
75 nautical miles deviation from centerline.
Aircraft symbol. The fixed miniature
aircraft symbol corresponds to the longitudinal axis of
the aircraft and lubber line markings. The symbol shows
aircraft position and heading with respect to a radial
course and the rotating heading (azimuth) dial.
Course deviation bar. The course
deviation bar represents the centerline of the selected
VOR, TACAN, INS or localizer course. The miniature
aircraft symbol pictorially shows actual aircraft position
in relation to this selected course.
VERT flag. Covers glideslope pointer
when not receiving glideslope information.
glideslope pointer displays glideslope deviation. The
pointer is in view only when tuned to a localizer
frequency. If the aircraft is below glideslope path, the
pointer is displayed upward on the scale. Each dot on
pointers aligned on the course pointer, are located 180
degrees apart. One always points in the direction of the
station, along the selected VOR radial or towards the
Navigation source annunciators. Five
different annunciators display navigation data sources.
They are: TAC for TACAN, GPS, INS, NV2 for VOR 2,
NV1 for VOR 1. WPT indicates arrival at INS waypoint.
Course knob. Positions the course
(22) Heading knob. Positions the heading
bug to a preselected heading.
Pilot's COURSE INDICATOR selector
switch (fig. 2-14). Selects desired source of data for
display on pilot's HSI and input to autopilot flight
NA V 1. Selects data from VOR
NA V 2. Selects data from VOR
TACAN. Selects data from
INS. Selects data from INS.
Controls/Indicators and Functions, Copilot's
HSI (fig. 3-9) (RD550R)
If both the pilot and copilot COURSE
INDICATOR select switches are in the
same position, except INS, the pilot
has sole control of course select
functions. The copilot can only
monitor deviation displays from the
selected system. A PILOT SELECT
annunciator will illuminate to notify
the copilot that both pilots have
selected the same receiver.
Distance display. Provides digital
distance of TACAN or INS waypoint distance. TACAN
distance is displayed in 1/10 mile increments. INS
distance to waypoint is displayed in whole mile
increments. The display will show dashes when the
distance input data is invalid or absent.
stabilized magnetic compass information on a dial
which rotates with the aircraft throughout 360 degrees.
The azimuth ring is graduated in 5 degree increments.
Lubber line marks. Fixed heading
HDG flag. Indicates loss of reliable
Digital COURSE counter. Provides a
digital readout of selected magnetic course.
Course pointer. The yellow course
pointer is positioned on the heading dial by the course
knob to select a magnetic bearing that coincides with
the desired VOR or TACAN radial, or INS or localizer
course. The course pointer rotates with the heading