waypoint location in terms of latitude and longitude.
Refer to Figure 3-109.
FW ABQ CTR
N 34° 33.21'
W 101° 40.01'
Figure 3-109. CTR 2 Page
(2) Inserting Center Waypoints Into Flight
Plan. Insert the Center waypoints into the desired
flight plan by returning to the CTR 1 page on the right
side and pressing the ENT button. The Center
waypoints are inserted into the flight plan in the correct
order. Refer to Figure 3-110.
If inserting the waypoints would cause the
number of waypoints to exceed 30, then no Center
waypoints are displayed and the CTR 1 page will
display, NOT ENOUGH ROOM IN FPL.
E N R - L E G
Figure 3-110. Insert Center Waypoints
After the Center waypoints have been inserted
into a flight plan, they may be viewed by returning to
the CTR 2 page. As long as the same flight plan is
displayed on the left side of the screen, the Center
waypoints may be viewed by displaying the CTR 2
page(s). The CTR 1 and 2 pages return to their
original format any time the specific flight plan is no
longer displayed on the left side. To view the Center
waypoints again, return to the specific flight plan,
select the CTR 2 page, and press the ENT button.
Center waypoints are stored as part of the 250
supplemental waypoints. When Center waypoints are
viewed on the SUP page or on the active waypoint
(ACT) page, they appear in the normal supplemental
waypoint format. Center waypoints that are part of a
flight plan show up on the OTH 3 page. Center
waypoints that are not part of a flight plan are deleted
from the list of user-defined waypoints when the KLN
90B is turned off.
Once Center waypoints have been inserted into
a flight plan, they are treated like any other waypoints
in the flight plan. If a flight plan containing Center
waypoints is modified in any way, new Center
waypoints may be computed. The original Center
waypoints are now part of the flight plan and new
Center waypoints are computed by treating the original
Center waypoints the same as any other waypoints in
the flight plan. If the interior of a flight plan containing
Center waypoints is modified, it may be desirable to
manually delete obsolete Center waypoints from the
flight plan before computing new ones.
bh. The Status Pages. There are four status
pages. The S TA 1 and STA 2 pages display
information pertaining specifically to the GPS receiver,
while the STA 3 and STA 4 pages display
supplementary information pertaining to the KLN 90B.
The STA 1 and STA 2 pages may be viewed at
any time to determine the status of the GPS receiver
and the GPS satellites being received. This includes
which satellites are being tracked, the satellites
health, the signal to noise ratio for each of the
satellites, the elevation of each satellite above the
horizon, and the estimated position error.
The GPS receiver in the KLN 90B is capable of
using signals from up to eight satellites to determine
position. A valid position may be determined using as
few as four satellites alone or three satellites with an
altitude input. However, four satellites alone or three
satellites with an altitude input do not necessarily
ensure that navigation can take place. The satellites
must be positioned relative to the aircraft such that
sufficient geometry exists to determine an accurate
position. The satellite constellation geometry is
continually changing as each satellite rises, travels
across the sky, and eventually sets relative to the
aircraft's position. The GPS satellites are not in
geosynchronous orbits positioned over the same spot
on the earth at all times. Rather, the GPS satellites
are in orbits that allow them to circle the earth about
two times each day.
(1) STA 1 Page. There will be two STA 1
pages if more than four satellites are being received.
The GPS state is indicated on line 1. Refer to Table 3-
17 for GPS status codes and their meanings.