Using the FMS
How do I program the FMC (flight management
This description was provided by Cormac
Shaw. I've added the illustrations and updated the description to
Here's the entire FMS panel, showing a fix that's been programmed in:
The buttons are laid out immediately
below the FMS instrument's display screen thus:
|Initialise: Clear out all
previously entered information, set your current location as the first
flight plan waypoint and display a blank waypoint 2 for you to enter.
|Previous: Display the previous
waypoint on the instrument's display screen.
|Next: Display the next waypoint on the instrument's
|Clear: Delete the data for the
currently displayed segment.
|Select: Set the currently
displayed segment as the active segment.
|Select an airport for the waypoint.
|Select a VOR for the waypoint.
|Select an NDB for the waypoint.
|Select a fix for the waypoint.
|Select any location by latitude and longitude.
|Toggle + or
- to specify north/south and east/west coordinates.
|Load a flight plan from a
|Save the current flight plan
to a file.
The remaining keys on the keypad are used
to enter waypoint identification and altitude. Remember it's a "virtual
keypad". You enter data by clicking with the mouse on the keys, not by
typing on the keyboard.
Here's how you enter a flight plan:
- At the start of your flight, while on the runway, click the INIT
button. You will see the top of the display change from "Plan Segment
01" to "Plan Segment 02". (What has happened - the FMC has entered the
airport you are currently at as the initial waypoint and moved the
flightplan on to the next entry for you to enter it. Press the PREV
button to change the view to "Plan Segment 01" and you will see
the first waypoint listed. Click NEXT to return to the blank "Plan
- To enter the second and subsequent waypoints, first click the
appropriate button for the type of waypoint, AIRP, VOR, NDB or FIX.
type in the code for the navaid (2-3 characters) / airfield (4
characters) / fix (5 characters) by clicking on the instrument's keypad
(not typing on your keyboard!). After entering the code, you need to
enter an altitude at which you will fly towards the waypoint. To do
this, move to the altitude line of the waypoint's details by clicking
the button to the left
of the "FLY AT" line on the screen. Then type in the required altitude.
Press NEXT to move to the next waypoint to enter its details in the
- To delete any waypoint, move to it by using the NEXT or PREV
button and then click on the CLR button.
- For the last waypoint, you will presumably enter an airport code.
Note that if you enter 00000 feet for this waypoint, you may fly into
the ground before you get there! If the penultimate waypoint is
relatively near your destination airport, then its best to enter the
pattern/approach altitude for the final waypoint. If the last leg is
going to be fairly long, then enter an appropriate cruise altitude.
That's the flight plan programmed. You
can save/load flight plans to/from discreet files at any time using the
LD and SA buttons on the bottom-left of the instrument itself.
Following a programmed flightplan:
You can of course, fly your flightplan
manually. Routes from one waypoint to the next are shown as bright red
lines on the EFIS Moving map (the heading bug is a dark red line). Most
aircraft that have an FMC will also have a moving map. Also, HSI
instruments can have their sources switched to GPS/FMC mode to show the
direction to the current waypoint. EFIS should also have a
To fly a flightplan by autopilot, first
take off! Once you've climbed out you can activate the flightplan. The
second waypoint should activate automatically as soon as you take off.
You can make sure by using the PREV key to get to the second waypoint
("Plan segment 02") and pressing the "->" button (to the right of
the CLR button). Engage HDG mode in your autopilot and set your heading
to intercept the FMS course, which runs from your initial position to
the second waypoint. (Usually your runway heading will initially take
you off course; you must intercept the FMS course to make the autopilot
Now set your HSI/autopilot source
selector to GPS and
press the LOC autopilot mode button to arm FMS course capture. As you
approach the course, the autopilot will lock on and turn toward the
waypoint. Press the autopilot VNAV button to select the waypoint's 'Fly
at' altitude for the autopilot. NB: if you want the autopilot to
throttle, you must set the desired speed and activate the autopilot's
ATHR mode manually.
The VNAV implementation in X-Plane 8.60 causes extremely violent and
abrupt response to altitude changes programmed in the FMC. You are
usually better off not using the 8.60 VNAV feature and managing your
altitude using the autopilot's VS or FLCH modes.
When the aircraft reaches the waypoint,
the FMC's active waypoint will automatically switch to the next Plan
Segment and any altitude change will be passed to the autopilot. The
receiver will always indicate which waypoint is currently active. You
do nothing unless you want to change the speed or rate-of-climb /
descent settings on the autopilot.
If for some reason, the FMC fails to
switch to the next waypoint automatically, you can force it to step
forward by using the NEXT button to display the desired waypoint and
then the "->." button to activate it. You can also use this
to skip waypoints if you so wish.
As you approach your destination you can
take the autopilot off the FMC by deactivating the GPS mode on the
autopilot. Fly your approach to the destination as normal, manually or
using the autopilot's other modes.
You can't auto-land the plane with the
FMC, because it doesn't have airport runways programmed into it. If you
want to make your flight entirely under autopilot control and know what
runway you're going to land on, you can program in a couple of fixes
that line up your flight path with the runway. During the last leg, set
up the ILS in the Nav receiver, and as you cross the last fix, switch
your autopilot source to the Nav receiver and press the glideslope
button to arm glideslope capture.
How do I
save and load flight plans with the FMS?
Thanks again to Cormac:
You can use the FMS itself to create and save flight plans and use them
again and again. Enter the flight plan data and then use the "SA"
button at the bottom left of the FMS panel to save it to a text
file. Give the filename a '.fms' ending and press the Return key
on your keyboard to save it. You can load saved .fms files to the
FMS using the "LD" key on the FMS panel.
'.fms' files are just text files so you can create them using any text
editor too. To understand the format required, make a complex one
with the FMS instrument using all possible waypoint types and
save it and open it in your text editor and study carefully.
[Editor's note: Make sure you get the format of the .fms file exactly
right! X-Plane tends to be very unforgiving of errors in its data
How do I create routes to use in
You have a couple of options:
- You can work them out yourself and toggle them into the FMC, as
- You can use the Goodway
flight planning tool, sold separately. Goodway creates complete
flight plans, ready to load into the FMC.
- You can use the Route Finder web page, described on the FAQ page on flying real airline routes.
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