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FS2004 Strange Occur: AI Plane can be "slew followed" but not waited for at arriv airport

You can see the day of the week I tested your FP's in the pictures. It was Wed. and Thur.

Monday is not a good day to test FP's if the day numbering system is off. FSX uses a different day for start of the week and it all depends on who wrote the code to make Monday 0. In FS9 the week began on Sunday, but in FSX its changed to Monday. So Monday becomes the 0 in the flight plans and Sunday becomes 6 etc.
You can see the day of the week I tested your FP's in the pictures. It was Wed. and Thur.

Monday is not a good day to test FP's if the day numbering system is off. FSX uses a different day for start of the week and it all depends on who wrote the code to make Monday 0. In FS9 the week began on Sunday, but in FSX its changed to Monday. So Monday becomes the 0 in the flight plans and Sunday becomes 6 etc.

Hi Jim,

Sorry for the long absence, but I was working on an involved spreadsheet showing various results with different inputs of days running, flight plans included/excluded, and individual legs included/excluded. I will include an image of the screenshot below. What I'm trying to demonstrate should be fairly self-explanatory, but any ambiguity I'll explain later today after I get some sleep and wake up later in the morning:


But suffice it to say, I think there's more going on here than simply a Monday thing. Your advice to not test on a Monday may be true some of the time, but I also had the flight spawning break down on other days of the week, per my experimentation, when the ranges of available days were not always the full M-F (and Monday was not even a day in question).

As for Monday being a code-1 vs. a code-0, depending upon whether or not I am using FS9 or FSX, I see your point to an extent, but I have never used AIFP in anything other than FS9, so for me, Mondays have always been a code-1. So long as I have never mixed and matched compilations from the different sim versions amongst the two different sim folders, I would think it should be irrelevant. Unless you have a strong argument for the contrary.

My ultimate solution to all this you may wonder? On MONDAY ONLY, I insert two extra legs in the morning from KBFL to KMRY (Monterey, California), and then from KMRY to KTVL. Then I continue the rest of the day as is. Then the rest of the week Tuesday through Friday, I just resume the regular schedule of KBFL to KTVL, so on and so forth.

My theory is that for some reason whatever was preventing that flight from spawning while waiting at South Lake Tahoe on a Monday, was corrected if coming from the central CA coast from west to east. I'm thinking the perpendicular approach to the Sierras instead of the parallel path directly over them, allowed the plane to somehow not "get lost". Though for some reason, it's only a concern on a Monday. Tuesday through Friday apparently does not have this problem-- unless my schedule runs T-F, W-F, or Th-F. Go figure.

Though maybe I should also test my Bakersfield-Monterey & Monterey-South Lake Tahoe leg insertions with alternate day of the week combos, to see if the KTVL spawn breaks down in any other situation. But I'm thinking for the most part I found a solution to the 5 day a week Monday through Friday challenge that I was having.

Thank you for your help and input, and sorry this has been ongoing and so darn involved for almost the past 2 months. I usually don't take these things to such dizzying depths of detail, but this one in particular was really bothering me.

-- John
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To continue with where I left off the other night... the 4 tests I ran were with the full set of flight plans, then all but legs necessary in FP4 to run the South Lake Tahoe test, then FP4 only with all its legs, and lastly FP4 only with only the legs directly concerned with Tahoe.

The results show an interesting pattern and a few exceptions as well:

1. In all 4 tests the Monday thru Friday schedule always had Monday "no-spawns", no matter what.

2. In tests #1 & #3, All combinations of days run (which involved a Mon) also resulted in "no-spawns" no matter what.

3. The major exceptions to Mondays were in Tests #2 & #4... but only in situations where the flight was set to run "Mondays Only".
And even then, the spawn time was 4 to 5 minutes later at 07:39 local, as compared to most of the other times on the spreadsheet test. The one common thread between tests #2 & #4 were that in both cases (whether ALL the flight plans were involved, or just FP4); only 2-the two most important legs of FP4 for purposes of the test were involved. Bakersfield to Tahoe, and then Tahoe back to Bakersfield... after which the plane would have a nice 6 day vacation in Bakersfield Tues-Sun, before running again the following Monday. Why this one factor should have made any difference at all is anyone's guess.

And at this point, I'm not sure it's worth anyone delving any deeper into finding an explanation than this. This whole escapade of mine has already been drawn out for almost 2 months as it is, but I thought it important to do my research since people did take the time to try and help me. The least I could do was try to do some of this investigative leg-work myself.

4. In all 4 tests, all other combinations involving Monday on the schedule that were not M-F or M-only (M-T, M-W, M-Thu) also all yielded Monday "no-spawns" no matter what.

5. On the subtractive side of the table (where I took days off the front of the week, until working my way to "Friday Only"), my test #1 and test #3 yielded a "no-spawn" in any situation where the day selected was the *FIRST* day of the work week for the given schedule. So no... it is not just 'Monday specific'! Note the cascading, diagonal effect of my "NO" cells on the right-half sides of each table-- thus denoting that condition on the first day of the schedule range.

6. Like in finding #3 above regarding "Mondays Only", note that in Tests #2 and #4, the "Friday Only" schedule on Friday was the exception where it would show a spawn. And again at the unusual and later time of 07:39... just like in the "Monday Only" condition. And again, the common thread between the two tests are that FP4's multiple legs for the entire day, were reduced to just the two necessary to run my test between the two immediate cities of Bakersfield and South Lake Tahoe.

7. The most minor consideration of all, but something I did notice: In tests #1 & #2 (involving all the flight plans in my traffic.bgl file), the Tuesday thru Friday schedule yielded a one-minute earlier than usual spawn time of 07:34 on a Thursday morning. Whereas in tests #3 & #4 (which involved only FP4), the Tuesday thru Friday schedule yielded the more typical spawn time of 07:35 on THE SAME Thursday morning.
All other things being equal, this anomaly seemed odd, but it is relatively minor, as compared to a spawn vs. no-spawn condition.

8. Finally, excluding all the places where there were either anomalies or "no-spawns", most of the spawn times (highlighted in the green cells) all shared the same parallel pattern of spawn times, looking down each column from Tuesday thru Friday-- "34-35-35-34". Once I saw this numerical pattern starting to emerge, its consistency was unmistakable. The only piece left to the puzzle is why the anomaly times, and what prompted them to take place when and where they did in my testing and on my spreadsheet.

Well in conclusion, if anyone cares to look this over and have a crack at explaining what all this might mean, I would appreciate someone else's perspective. It does seem rather odd that day of the week should have anything to do with whether an AI aircraft will spawn at an arrival airport (for a given created leg), if the user is sitting waiting at the arrival airport.
And it seems equally odd that my solution of flying from Bakersfield to the Central California Coastline at Monterey, and then heading inland (on just Monday morning only, in order to solve the Monday problem), would have made a difference, and yet it did!

But on the other hand, if everyone feels we've pretty much beat this horse to death, and there's no more useful discussion on this to be had, then I can understand, and I'm willing to call it a day on this thread and this project. Again, thank you everyone for your help, input and advice on this post.

-- John
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