Choosing Taxiways never seem to work

[Dane]

I have noticed for sometime now that whenever I choose certain taxiways EFB2 always issues an error - No taxipath can be found....

Maybe I am doing something wrong because the taxi paths do exist - see example attached...

 

[aivlasoft]

Hi Dane

You are not doing anything wrong. To be able to find a way along certain taxiways it is required that all segments of the taxiway are properly connected. Properly in this regard means that the lat/long coordinates of an ending point of a segment are equal to the coordinates of the beginning point of a next segment. Sometimes developers do not connect the segments exactly enough which usually is not visible to the eye and therefore nobody complains, but an algorithm cannot proceed then.

 

If you let us know which airport it is (ICAO code, developer, simulator) we may try to investigate.

[Dane]

On 7/5/2022 at 11:05 PM, aivlasoft said:

Hi Dane

You are not doing anything wrong. To be able to find a way along certain taxiways it is required that all segments of the taxiway are properly connected. Properly in this regard means that the lat/long coordinates of an ending point of a segment are equal to the coordinates of the beginning point of a next segment. Sometimes developers do not connect the segments exactly enough which usually is not visible to the eye and therefore nobody complains, but an algorithm cannot proceed then.

 

If you let us know which airport it is (ICAO code, developer, simulator) we may try to investigate.

 

The airport was at KDCA, I am attaching two screen prints.  Note that in the one titled EFB2 Taxi there is no problem as your system automatically drew in the taxi route.

But in the other example titled EFB2 Select Taxiway Errors, when I click on the path letter like in this case the letter K, you get an error.  The reason why I clicked on a path letter was because I was following what ATC had indicated for my taxi route.

[aivlasoft]

Hi Dane

thank you very much for the further information and the screenshots. There have been found two independent issues:

1) There are two further taxiway segments (after taxiway 'P') which are also named 'K'. This means that taxiway 'K' is not entirely connected and therefore when using named taxiways, the algorithm is not returning a useful result.

2) Also after fixing the taxiways layout, the algorithm still does not work properly which I have to fix.

 

For the time being it is recommended to simply use the default selection which provides reasonable results.

[aivlasoft]

Although the algorithm could be slightly improved in the meantime (available with next update), it brought up that the outcome of the algorithm is highly and mainly depending on the quality of the taxiway layout provided by the simulator's scenery files.

 

This means:

• all segments of a named taxiway must be properly connected
• all segments of a named taxiway must be consistently named
• a named taxiway must not have branches

Unfortunately these requirements are not fulfilled at all airports, especially not at the generic-airports from MSFS. To our knowledge these generic airports will be generated automatically using kind of a KI algorithm which sometimes does not provide a meaningful taxiway layout. It goes without saying that we cannot manually correct approx. 5 to 10 thousand airports to get a proper layout.

Unfortunately even the payware airports are not always properly designed in this regard. On many of these airports we have found inconsistently named and branched taxiways.

 

Conclusion:
Use the function 'named taxiways' with caution. Sometimes the result is good, sometimes not.
Using just the 'shortest path' (provided when NOT using the 'named taxiways') usually brings up a good result.