Simulation Example

Turn at the North Pole


Easy... rotating and moving map,
just mouse wheel zoom to see all details.

Executing our plan

In the previous section we made a route. Now we will fly it with the simulator to check for errors and such matters. We also switch the route guidance on. If we had an autopilot connected to the computer, we could use that to steer the "ship". But we can as well steer our self based on the measures on the screen.

Guidance

The guidance consist of two windows. On the left there is the destination indicator and on the right there is the leg indicator. With the buttons we can choose either to show destination calculations for the next way point or for the entire route. The two buttons on the left are way point advance buttons. These allow one to advance the next way point manually. Normally the program self detects the way point change, but it can also be done manually anytime.


"On final, runway 08"

Speeding up simulation

To speed up the process we set the speed to 2000 km/h. We let the altitude to be around 500 meters. This would be a bit too low altitude.

Shortest track calls direction changes during leg

Since the guidance uses shortest distances between any points (great circle navigation) the course over the ground should be time to time updated. The autopilot would do that automatically. This direction to the target is named bearing (BRG). It is based on our current position and destination position.

How to stay on course

As long as our COG is the same as BRG we are heading directly to the destination. On the right, there is the cross track error (XTE) visualized. This is the real (great circle) measure. On the map it might show differently, since route lines are shown straight on maps (to speed up the drawing).

Minimize XTE

To make the fastest and most economical flight we try to keep the XTE minimal. If there is cross wind we have to correct to the wind. Since our simulator runs the same route as the guidance is set to, the XTE stays almost zero. In real flight we might be far off the best track.

Green bars

The green bars below are the HDOP and VDOP quality indicators. They are so defined that as long as the left bar is green we have a good position and if the right bar is also green we have an accurate altitude also.


"Should I stay or should I go? :)"

Terminology

  • WPT - Way point name
  • RTE - Route name
  • DST - Distance to way point or route end point
  • ETA - Estimated time of arrival to the way point or route end point
  • TTG - Time to go to the way point or route end point
  • VMC - Velocity mad on course
  • CMG - Course made good
  • BRG - Bearing to the way point
  • LEG - Leg name
  • XTE - Cross track error (L/R = Left or right)
  • COG - Course over ground (Ground path direction)
  • HDG - Heading of the vehicle

Improvements

Now we have tested our plan and we could now add more detailed maps about the way points. Runway maps, Station Nord maps, etc. We could make the plans more and more detailed; or just be happy with what we have now.

We could also add additional routes with different names to our data set.

Exporting data to be used elsewhere

If we have different computers running Master Navigator we can export some details to those or copy the whole data set as it is to the other machines.


Route guidance activated and route selected. First leg from EDCK to ENKB. This leg is 980 km long and it's initial direction is 353 degrees (true north). On the left we can see that the distance to the way point is 660 km, and bearing to it is 353 degrees. We are travelling fast: 2017 km/h (simulator sped up). We are on the course, since our COG is 353, and the red target pointer is on the white pointer.


The guidance always takes the shortest way between any two points (great circles).




Cross track error (XTE) is 107 meters right. We should steer more to the left.


The initial leg direction was 349 degrees true north. But now we have already corrected 10 degrees to 339 since we are taking the shortest path. We are doing great circle navigation. The map indicates that we would be to the left of the path, but the XTE display says correctly. The difference is because the lines on the map are drawn straight from point to point (to speed up), and maps have different projections. The XTE display is always prioritized over maps since maps have different projections which distort to certain level.


WPT display switched to RTE display. WPT state shows values to the next way point en route. RTE state calculates values to the end of route (ETA, Estimated Time of Arrival among others).











Simulation snap shots