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By Paul Mort

Overview

Hello and welcome to this tutorial. This time I will be covering the use and facilities of the updated default FMC used in X-Plane 11. As I am sure you all know, in most cases in X-Plane 10, the FMC in a large aircraft was a fairly basic 'point and shoot' affair, with the exception of good payware models. This is not so in X-Plane 11. Here we are given a more useful and feature-packed FMC as standard, and it is from this we will take our example for this tutorial, using the default X-Plane 11 Boeing 737-800.

The Route

Being from the UK, naturally I chose a route in an area I was familiar with. Starting from my local airport, Manchester International (EGCC), I was going to fly the short distance to Bristol Airport (EGGD). Using an online route finder, the data for my flight was mapped out, as shown below.

Cruise altitude between 5000 and 5000

EGCC (0.0nm) -SID-> MONTY (42.6nm) -N42-> RETSI (67.9nm) -STAR-> EGGD (136.0nm)

Details:

ID TRK DIST Coords Name/Remarks
EGCC 0 0 N53°21'14.00"
W002°16'30.00"
MANCHESTER
MONTY 229 43 N52°53'34.00"
W003°10'26.00"
MONTY
RETSI 154 25 N52°30'42.00"
W002°52'33.00"
RETSI
EGGD 174 68 N51°22'57.61"
W002°43'08.76"
BRISTOL

Note: Tracks are magnetic, distances are in nautical miles.

EGCC SID MONTY N42 RETSI STAR EGGD

This is a fairly basic route and ideal for the purposes of this tutorial.

The FMC

To begin with, we will use Runway 23L as the departure runway, as our route takes us in a south-westerly direction. So here we are on Runway 23L at Manchester, ready to roll with the pop out FMC (Figure 1) on view.

 

X-Plane FMC
Figure 1

 

If we take a closer look (Figure 2) we can see the default FMC index page outlined in red, and that it is page 1 of 1. The message at the bottom also tells us that the navaid database is not current but this can be easily rectified with an update from the Navigraph web site (for a small fee). However, it is still functional, so for the purpose of this tutorial it can remain as it is.

 

X-Plane FMC
Figure 2

Keeping with the same image of the FMC (Figure 3), in order to simplify which of the twelve soft keys to press (six on the left and six on the right), refer to the following:

 

X-Plane FMC
Figure 3

 

Firstly, by pressing key L1 over on the top left-hand corner, we are taken to the STATUS page (Figure 4) which gives details of the current state of the navaid database. This is not important to the route but is still shown nevertheless, for completeness.

X-Plane FMC
Figure 4
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X-Plane FMC
Figure 5

Now for the first element of entering our data for the current route.

If you press the key R6 it will bring up the DATABASE page (Figure 5).

We enter our data, using the alpha numeric keys, into the area known as the scratchpad between the cyan square brackets. To clear the scratchpad of any previous data, press the CLR key on the bottom right-hand corner. Having entered our Departure ICAO (in this case it will be EGCC) into the scratchpad, we then transfer that into the IDENT position by pressing L1. What were originally four dashes, now change to our Departure ICAO and our starting airport data is displayed (top right).

Waypoints

Now it's time to enter our waypoints into the FMC which is done by clicking the FPLN key, outlined in red (Figure 6). We are presented with the ACT FLPN screen into which we can enter the origin airport, destination airport and navaids required, as our flight plan shows. As before, clear the scratchpad of any data and type in the departure airport (EGCC). L1 transfers it to the ORIGIN boxes. Notice that when a successful transfer occurs, the scratchpad becomes empty again. Now for the destination. Type our destination airport (EGGD) into the scratchpad and transfer it to DEST using R1.

CO ROUTE is optional and is the company route for fuel usage. It is not covered in this tutorial so we will leave it blank.

The FLT NO displayed below the destination data on the screen (Figure 7) is our flight number which can be anything you like, so we'll use XP737 and transfer it to R3. Our first waypoint is MONTY at 43 miles, 229 degrees, so input it into the scratchpad and transfer to R5. Doing this will show a direct route to the waypoint. We could also enter a designated airway name into L5, in which case the route would be via that airway to the waypoint, but we'll leave it blank this time in order to get a more direct route.

X-Plane FMC
Figure 6
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X-Plane FMC
Figure 7

In Figure 7 you will notice that a cyan bar lights up above the EXEC button after we enter our data. This is asking for confirmation that our details are correct. Hit the EXEC button to confirm this and the light will go off again. Failure to do this whenever the EXEC button is lit will result in the aircraft not following the flight plan. Our first waypoint is entered, and to continue with more, we now need to view our ACT LEGS page (Figure 8), by clicking the LEGS button situated below the FPLN key.

X-Plane FMC
Figure 8
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X-Plane FMC
Figure 9

We need to enter the next waypoint, RETSI, into L4 in the ACT LEGS page. Remember to hit that EXEC button too! Don't enter the destination airport as we have already specified that in the ACT FLPN page.

That's it for the waypoints.

Flight Data

Now for some important data about the flight. Press the CRZ button located next to FPLN to bring up the VNAV CRUISE page (Figure 10). A simple entry of our cruise speed of 250 knots and a cruise altitude of 5000ft, are in turn entered into the scratchpad, and again transferred to L1 and R1 respectively. If we now return to the LEGS page (Figure 11), we can see our speed and altitude references displayed in green on the right.

X-Plane FMC
Figure 10
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X-Plane FMC
Figure 11

These references are used manually if flying LNAV or automatically if flying VNAV.

Departure / Arrival Data

The final task on the way to a fully programmed FMC is to input the details for the departure/arrival runways and any SIDS or STARS required in the route.

If you hit the DEP ARR key in red (Figure 12) it will then shows the DEP / ARR INDEX page. Here you will see your previously programmed departure and arrival airports in the center.

By pressing the key L1 it will bring up the options to input the departure runway (Figure 13). We have selected R3 for runway 23L. No SID is specified.

X-Plane FMC
Figure 12
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X-Plane FMC
Figure 13

Once again, press the EXEC key to enter. L6 returns us to the DEP/ARR INDEX page where we can now select R2 for the arrival runway and STAR. No star is specified in our route plan so just the runway is required. We will choose R2 for runway ILS27 (Figure 14).

 

X-Plane FMC
Figure 14

Discontinuity Errors

You may see the word 'Discontinuity' on the screen of the FMC. The explanation in a nutshell for this, is shown below (Figure 15).

 

X-Plane FMC
Figure 15

 

The above image shows the flight plan of an aircraft with 4 waypoints programmed into the FMC. Marked in magenta is the route it will take from the first to the fourth waypoint. According to the arrival runway data we supplied, the FMC works the approach out shown in blue. Because the last waypoint, number 4 we entered, is not the same point as the first approach point, the FMC tells us there is discontinuity or dead space between waypoint 4 and approach point 1, which is not accounted for in the flight plan.

X-Plane FMC
Figure 16
X-Plane FMC
Figure 17

So, looking at pages 1 and 2 (Figure 16 and Figure 17) of the ACT LEGS, we have a discontinuity between our last waypoint of RETSI and our first approach waypoint of CI27. Fortunately, this is easy to correct. Just click button L1 on page 2 (CI27) which puts CI27 into the scratchpad. Now click on button L5 on page 1 (Discontinuity). This effectively removes the discontinuity and stitches the two parts of the flight plan together (Figure 18).

 

X-Plane FMC
Figure 18

 

The easiest way to tell if your FMC has been successfully programmed, is to look at your screen, and if you are following a magenta line, then it is indeed correctly programmed (Figure 19). So following the standard autopilot procedure, we can get the aircraft to fly the complete route, and if we use VNAV, you can also observe the stated altitudes.

 


Figure 19

 

I hope you enjoyed this tutorial and by the end of it, feel clearer about getting the best out of the default FMC in X-Plane 11.