When ATC controllers stop communicate with you, the reason can easily be CenterSectors.dat
file, which defines the geography of control centres. The source of problems are XXX points (FIR boundaries) too close to each other and gaps between centres. Lets look at the geojson map of a LSZH-LOWW flight plan.
Partitioned sectors and their rugged geographic boundaries cause repeating and quick changes of ATC frequencies, which is not only unrealistic, but PF3 often cannot cope with it. There are even some gaps in the coverage, which usually break ATC immediately - look at the zoomed-in portion of the previous flight path, grey X point means that the next centre is unidentified:
Now the good news - you can prevent these errors from influencing your flights. The first option is to edit CenterSectors.dat
. I am not going to explain how, because I do not recommend editing default files as a general solution. Edited centres should have as straight boundaries as possible and must overlap (no gaps). Of course, always backup the original file!
If and when I finish editing the file, I can share it, but it will take some time as I do it ad-hoc. Here is an example.
I created three new regions according RW maps, with some simplification (I think that Munich radar really takes care of western Austria, but it is irrelevant for this demonstration). Notice the overlaps, which actually simulate real practices – hand-offs are done before crossing the boundaries, centres take care of airplanes flying in the neighbouring FIRs for the communication efficiency. As you can see on the map, PF3 deals with overlapping regions perfectly. In this case, Zurich - Munchen - Wien. That's it. No unnecessary switching of frequencies, no gaps. All flights with similarly adjusted geography of centres work like a charm, no interruptions of ATC at all, no lack of climb or descent instructions, PF3 at its best
Now the second alternative, an easier one: Know your flight plan, control centres and frequencies
. In RW, you should be well informed about all control centres along your flight path. A good way is to open http://geojson.io
and drop there your current .json file from .../PF3/Flight/FPP
directory. You will see your flight path with all waypoints and centres. Get familiar with them and prepare for eventual problems associated with adjacent XXX points (i.e. quick changes of frequencies) or gaps between sectors (marked as grey X points). Then, when flying, open pf3_display
program (I do it on a networked laptop) and monitor your progress, same way as RW pilots do. Check if indicated "Next WP" and "CTRLFreq" are correct. Here are the problematic scenarios and their solutions:
1. "Next WP" is not appropriate, i.e. it shows an already overflown waypoint. Solution: request direct to your correct next waypoint.
2. "CTRLFreq" is empty. Solution: tune the appropriate frequency on COM1, according your current location.
Always check "Next WP" first and correct, if needed. Then check "CTRLFreq" and correct, if needed. After these corrections, ATC will resume normally.
These problems do not always happen, but if they do, you as PIC should be able to solve them, if you have appropriate positional and ATC awareness. I found these challenges to be entertaining.