TM 1-1510-223-10
2.
LA line selector switch - Depress
to select NAV DATA information
box. The following information is
provided in the NAV DATA box:
(a)
Present position. The
present position (RESENT POS) display shows the
actual latitude and longitude coordinates of the point on
the earth's surface directly below the aircraft at any
given instant.
(b)
Navigation status. The
navigation status display (NAV STATUS) shows the
alignment status of the INS by a number (1 through 9).
(c)
Ground
track
angle.
The ground track angle (TRK) is the clockwise angle
from true north to an imaginary line on the earth's
surface connecting successive points over which the
aircraft has flown (ground track).
(d)
Wind direction and wind
speed. Wind direction and wind speed are shown in the
TRU WIND display. Wind direction is the clockwise
angle from 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
(DFr 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.
L5 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
1 and 9 are scratchpadded, the
time and distance between those
two waypoints will be continuously
displayed.
(7)
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.
(8)
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
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