TM 1-1510-224-10
true north to the wind velocity vector. Wind speed (knots)
is the velocity of the wind with respect to a point on the
earth's surface. Zero wind speed and direction will be
displayed when there is no true airspeed input.
(e)
Desired track. The desired track
angle (DES TRK) is the clockwise angle from true north to
an imaginary line on the earth's surface connecting
successive points over which flight is desired (desired
track). The line describes the great circle course between
two successive waypoints, and is further defined by the
intersection of a plane and the earth's surface when the
plane passes through the two successive waypoints and
the center of the earth.
(f)
True heading. The true heading
(TRU HDG) display is the clockwise angle from true north
to the aircraft centerline.
(g)
Track angle error. The track angle
error (TRK ERR) display is the angle between the
aircraft's actual ground track and the desired track, or the
angular difference between ground track angle and the
desired track angle. Track angle error is left when the
actual track angle is less than the desired track angle and
right when the actual track angle is greater than the
desired track angle.
(h)
Drift angle. Drift angle (DFT ANG) is
the angle between the airplane centerline and ground
track or the angular difference between the true heading
and ground track angle. Drift angle is right when ground
track angle is greater than true heading and left when
ground track angle is less than true heading.
(i)
Cross track deviation. Cross track
deviation (XTRK DEV) is the shortest distance between
the aircraft's present position and the desired track.
Cross track deviation is left when the present position is
left of the desired track and right when present position is
right of the desired track.
1.
LS line selection switch Depress.
If
the
scratchpad
is
empty,
present
position
and
NAV
STATUS will be displayed. If a
single valid waypoint number is
scratchpadded,
the
time
and
distance to that waypoint will be
continuously displayed. If two
valid waypoint numbers between
I and 9 are scratchpadded, the
time and distance between those
two
waypoints
will
be
continuously displayed.
(5)
INS operation.
1.
INS mode selector NAV when desired nav
status is achieved.
2.
B mode selector switch Depress to call up
FLIGHT PLAN page.
3.
R5 line selector switch Depress to call up
NAV SETUP page.
4.
R5 line selector switch Depress to call up
INS SETUP page.
5.
L3 line selector switch Depress to select
LEG CHANGES to AUTO or MAN.
6.
R2 line selector switch Depress to select
roll limit OFF or ON.
7.
R3 line selector switch Depress to select
AUTO MIXING mode: TACAN, DL, GPS,
or OFF.
(6)
INS update.
1.
R5 line selection switch Depress to select
INS UPDATE STATUS page.
2.
Valid waypoint number or coordinates
Enter into scratchpad and depress L1.
Update
box
will
be
displayed
for
approximately 30 seconds. The data within
the box will show:
The scratchpadded coordinates or those associated
with the scratchpadded waypoint.
The current NAV status number.
The difference between the scratchpadded waypoint/
coordinates and the INS position when the update button
was depressed. This difference is displayed in nautical
miles and tenths if LAT/LONG is selected, and in
kilometers and tenths if UTM is selected.
3.
To accept the INS update Depress L1
(UPDATE ACCEPT).
4.
To reject the INS update Depress L2
(UPDATE REJECT).
(7)
INS stored heading procedure. An accurate INS
heading and the local magnetic variation will be stored in
the computer memory by performing the stored heading
shut-down procedure. This will allow the INS to be ready
for the next flight in a shorter time period.
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