(q) HDG SYNC Button. The center push
button on the data selector is a HDG SYNC selection.
Pressing the HDG SYNC button will automatically slew
the selected heading bug to the lubber line. When
FMS 1 is the selected navigation source and the HDG
SYNC button is pressed, the FMS heading bug is
displayed on the MFD and the navigation source label
FMS changes to FHDG. The FMS heading bug then
syncs to the selected heading.
(r) DATA Selector. The data select
knob is a dual concentric blind selector with a center
push button. The outer knob provides sequential
selection of FMS data to include groundspeed (GS),
True Airspeed (TAS), time to go to next waypoint
(TTG), Elapsed Time (ET) from WOW, and off-no data
(s) CURSOR Reset. The cursor reset
(CURSOR RST) button resets the cursor to the aircraft
a. Description. The Electronic Attitude Director
Indicator (EADI), Figure 3B-4, is an instrument whose
primary function is to display the aircrafts current
electromechanical indicators into a single electronic
display. This display consists of the Attitude Display
Indicator (ADI) display page and the Primary Flight
Display (PFD). The default display format on the EADI
is the ADI format on powerup.
The ADI presents attitude, comparator warning
annunciations, decision height setting, and rate of turn
indicator. Other parameters that are displayed as a
function of pilot selection are DH annunciation, Radio
Altitude, Rising Runway, Vertical Deviation (GS or
VNAV), Speed Deviation, Flight Director Command
Bars (V Bars), Aircraft Symbol, Lateral Deviation,
Marker Beacons, Flight Director Annunciations, and
Course Source (LOC, VOR, or FMS).
b. ADI Display Symbology.
(1) Pitch and roll attitudes are indicated by
the position of the blue sky and brown ground
relationship. The aircraft symbol is outlined in white
with a black interior. Precise pitch attitude is provided
by the position of the pitch scale with reference to the
nose of the aircraft symbol. Precise roll attitude is
provided by the position of the moving roll pointer with
reference to the roll scale. The pitch scale disappears
behind the roll pointer and the lateral deviation pointer
to prevent interference between the symbols. Roll is a
continuous 360 display and pitch is 90 display.
If an attitude sensor failure occurs, an attitude
flag appears which consists of a red box with black
letters ATT. An attitude flag removes the pitch scale,
roll scale, roll pointer, sky/ground raster, flight director
annunciations and command bars from the display.
(2) The pitch scale, Figure 3B-5, consists of
2.5 increments between 30 to 40
Approximately 40 of the pitch scale is visible at any
(3) The roll scale displays the current roll
attitude of the aircraft. It rotates about the aircraft
symbol such that the aircraft roll is graphically
indicated on the bank scale. The bank scale contains
the 10, 20, 30, 45, and 60 increments. The rest
of the scale is white. If the roll input is invalid or
unavailable, the bank scale and pointer are removed
from the screen and the ATT flag appears.
(4) If the pitch attitudes exceed + 30 or - 20
or if the bank attitude exceeds 65 all information
except the aircraft symbol, attitude, and attitude sensor
annunciation are removed from the ADI, refer to Figure
3B-5. All ADI information is restored when at + 25 or
-15 of pitch or 60 of roll. If the PFD is displayed
when an extreme attitude condition occurs, the
excessive attitude ADI page automatically is displayed.
Refer to Figure 3B -6. The PFD is not selectable until
the extreme attitude condition is removed and then it
must be reselected.