TM 1-1510-218-10
3C-85
e. Active Flight Plan Waypoints and Courses.
(1) Flight Plan Overview. The active flight
plan is a list of up to 60 waypoints, stored in the order
they are to be flown. The flight plan is maintained
through
addition,
modification,
or
deletion
of
waypoints. When a waypoint is passed, it is retained
in the flight plan history list, where the last 39 passed
waypoints are maintained in order. History waypoints
are identified in the flight plan with a # symbol
following the waypoint number and may be viewed by
scrolling the Flight Plan page using the - key. The
crew may delete history waypoints, using a – entry, but
may not enter waypoints into history.
The FMS-800 guidance function assists in
execution of the flight plan by determining deviations
from the desired flight plan and controlling the
sequencing of waypoints. When automatic leg
advance is selected via the Flight Plan page, waypoint
switching is determined as a function of aircraft speed,
wind, and magnitude of course change to provide turn
anticipation. A waypoint alert is generated prior to
reaching the waypoint switching point for the next leg.
(a) Flight Plan Loading. There are three
ways to enter flight plan data.
1. Through the active flight plan.
2. The alternate flight plan.
3. The data cartridge catalog.
(b) Data Cartridge. The data cartridge
is a storage device containing a catalog of Alternate
Flight Plans (AFP). The cartridge can be modified at a
Mission Planning Ground Station (MPGS) which can
store thousands of unique flight plans. Up to 40 flight
plans at one time can be transferred from the MPGS to
the Alternate Flight Plan Catalog in the data cartridge.
The pilot can then choose one of these AFP's from the
catalog on the dat a cartridge to load into the AFP in
the CDU. After loading the AFP, the pilot can make
any changes or transfer the AFP directly to the active
flight plan. If desired, the pilot can also modify an AFP
and save it back to the catalog in the cartridge. Refer
to Figure 3C-31 for a summary of the information flow.
(2) Flight Plan Active Waypoint. The
waypoint that all flight instruments and CDU guidance
display is referred to as the active waypoint. Pressing
the FPLN key on the CDU accesses the Flight Plan
page with the active waypoint displayed as the TO
waypoint. This is signified by ¯¯ pointing to the active
waypoint.
(a) Associated with the active waypoint
are the following parameters, which are displayed on
the Flight Plan page. Refer to Figure 3C-32 and Table
3C-23.
1. Current desired inbound course
measured at the waypoint, not
current desired track at aircraft
position.
.
Figure 3C-31. Flight Plan Management
