Understanding taximnt import

[snomhf 14]

Dave,

Since importing airport data using the taximnt utility appears to work considerably differently (much better!) now in v2.6.1.2 from what is described in the manual, I have been trying to understand how it now works.   I'm hoping to get some clarification on my observations.

I started by changing some of the taxiway names,  parking spots,  airport flow rules, etc, for the airport KSJC (San Jose, CA) in the apt.dat of Global Airports so I could easily tell when taximnt imports it and if there are any parts it doesn't import.   After observing taximnt's import behavior, I then found a download of that same airport in the X-Plane download web site and made similar but different changes so I could tell the difference between the two versions.  I repeated the tests and recorded when and what taximnt imported from the Custom Scenery version.  I'm hoping you might verify my findings and correct any misunderstandings.

OBSERVATION 1:  For some time,  I had myself convinced that P2A would sometimes import at least the taxiway routes from apt.dat because it seems like the last few versions do not struggle with where the hold short points are without me having to even open taximnt.  In these recent tests however,  I see no evidence that there is any sort of AUTOMATIC importing taking place as the changes I made to some of the taxiways never show up.   Am I correct in concluding that P2A NEVER automatically imports any part of the apt.dat file and that I have to explicitly import them?

OBSERVATION 2:  Neither of the versions of KSJC I tested have any "Hold Short" tags in the apt.dat files at all yet when I import them into taximnt,  the Hold Shorts look perfect; even ILS Hold Shorts are there as well!  Does this mean we are done worrying about these tags?   Can I strike the discussion of these tags from the manual?   Can I toss my program that laboriously adds these tags to airports?  If so, I'm curious, how are you now accomplishing this?

OBSERVATION 3:  Before I imported anything, I looked at the airport image in taximnt for KSJC.  It showed a runway (11-29) that no longer exists.   Turning on "Show Runway Names" included that deleted runway.   Is that because, before importing,  that airport is coming from the old FSX database?  Curiously, when I imported the airport, that old runway is still there.   Apparently taximnt does not import all parts of the apt.dat file.  Right?

OBSERVATION 4:  The Airport Flow Rules in the KSJC apt.dat file defines runways 12L and 30R as departure only runways and 12R and 30L as arrival only runways.  There is also a "Calm Winds" rule that defines the 30 runways as the default.  After importing with taximnt,  the runway table in taximnt still shows all the runways as bi-directional and the default runways are not defined either.   It is apparent that taximnt is not loading the Airport Flow Rules from the apt.dat file.   It this correct?

QUESTIONS

I could find no reference to these taximnt checkboxes in the manual:

* Overwrite Taxiways At Modified Airports

* Overwrite Gates At Modified Airports

* Mark Airports as Unmodified

I have the first two checked but the last one unchecked.   What do these options do?   Are they important?

 

I really love the surprising new behavior of taximnt and would especially like to get to the bottom of all this and get the manual corrected accordingly.   I'd be happy to send you the corrections if you would kindly help me clarify everything.

Thanks much

-mark

 

 

[Dave-Pilot2ATC 864]

Hi Mark,

Yes there have been some enhancements that didn't make it into the documentation yet. 

I'll take each observation one at a time.

#1: P2A does not import anything from scenery automatically.  It does attempt to deduce missing info, like runway hold short points, to enable reasonable instructions despite bad/outdated data.

#2: A while back logic was added to define hold short points based on runways and taxiways information, even if the hold short points were missing in the apt.dat file.  Another user who was frustrated with adding Hold Short points manually helped develop the logic with me.

#3: The import operation flags runways that are in the original definition and not in the import.  If you look at the Runways tab in Taxi Mnt, they should have a '**' next to them.  Just uncheck the Landing and Takeoff boxes and they will not be used for runway assignment.  

#4:The current import logic does not capture the flow rules.  That is on the list for future work.

The options you ask about are related to FSX/P3D bulk imports.

Overwrite Taxiways At Modified Airports

* Overwrite Gates At Modified Airports

There is a list of airports that have been manually modified and saved.  When you do the bulk import from FSX/P3D, you may want to preserver these manual changes, so those 2 options are there to enable this.

Mark Airports as Unmodified

This option will remove all airports imported in a bulk import from the modified list as their taxiways or gates are imported.

Hope this clears up the confustion.

Thanks,

Dave

[snomhf 14]

Thank you for taking the time to clear this up.   I really appreciate that.

Concerning #1,  I thought I was imagining the trouble I used to have with certain airports.  These airports work fine now and I was certain I had not imported them.   It gave the impression that the import was taking place automatically!  This makes perfect sense now.

So just to clarify on #2.   The "Hold Short" and "ILS Hold Short" tags are ancient history now?  Your answer on this leaves me thinking that if a taxi route in the apt.dat file has a hold short tag you will honor it (legacy) but otherwise you will compute the hold shorts from the taxi route geometry alone.  Am I reading you right on that?

Your response to #4 sadly clears things up too with respect to the constant disagreement on active runways between ATIS reports, World Traffic 3, and P2A .  I wrote a tool to extract the flow rule from the apt.dat file but editing the runway table in taximnt still has to be done by hand apparently.

Your answers on the checkboxes settles that.  These three options (four actually) do not apply to X-Plane at all and can be ignored.

Thanks again Dave for helping me understand how all this works now.

-mark

[Dave-Pilot2ATC 864]

You're exactly right on #2.

Dave