AI Go Arounds

[agent00729 3]

Hello,

I have a question regarding unusual AI behavior. I am also using AI Separation, but only noticed this after using RC4. Sometimes (typically after I land), I noticed that AI flying the same approach as me after me will not land, and will instead go around, even when the runway is seemingly clear. The next plane on approach will then come close to the runway before going around last minute, and the cycle continues forever.

I think it might have something to do with AI landing clearance? Maybe some AI are cleared to land, then moved out of the way by AI separation or RC4 on final, and so no other planes can land until the plane that was cleared lands.

Is there any solution to this? Not sure if it’s related, but I also noticed some AI will be cleared to taxi onto the runway and wait, without ever getting cleared to takeoff.

[Ray Proudfoot 8,927]

@agent00729, RC4 is not interested in any Ai once you land and exit the active runway. You are instructed to contact Ground and thereafter can choose to listen to your critique or close RC4.

It sounds as though Ai Separation is controlling those Ai. The whole process of Ai behaviour hasn’t really been addressed in any versions of P3D and remains much the same as it was 15 years ago. The difference now is huge numbers of Ai can be injected into P3D and it becomes very difficult to control.

We just have to live with it. RC4 will only attempt to control Ai that are either closing in on your aircraft when behind you or are ahead but you’re catching them up. They can slow right down but then accelerate enormously quickly as RC4 battles with the Ai engine in P3D.

[Ray Proudfoot 8,927]

@agent00729, was my reply any help to you?

[agent00729 3]

Hi, thanks for getting back. Yes it was, I appreciate it. I’m starting to think that maybe the problem was that the aircraft behind me on final are too close, and then they get cleared to land just after me, but before I touch down. So maybe they are forced to go around? And since they are still cleared to land, no other plane can land until they do, so everyone else also goes around. I’m not sure if that’s how the ai engine works or not. I did notice on my TCAS that the aircraft behind me were VERY close to me. Also, there was an aircraft in front of me, but I didn’t even see them when I landed, making me think they disappeared, even though I’m pretty sure the TCAS was still showing them sort of “hovering” in front of the runway. 

I will try and test it again this weekend. I upped the AI separation “no-move zone” from 8 no from the runway to 10 nm. Maybe that will make a difference. Not sure if anyone else has noticed similar problems?

[Ray Proudfoot 8,927]

@agent00729, RC cannot do anything with Ai behind you, only those in front and I suspect the Ai that was in front of you was propelled at high speed out of your path. As you’ve probably found it’s extremely difficult for external programs to have any real control over Ai when they’re airborne.

Have a chat with the author of Ai Separation. He can probably cast more light on how he’s controlling those behind you on final. If only LM would improve P3D in this respect it would greatly improve Ai handling.

[agent00729 3]

Tried again yesterday, had the same issue. Aircraft was just a tad in front on final and sped up and did not descend, with no other aircraft around, making me think it’s a radar contact issue and not ai separation. The endless go arounds followed after I landed on that runway. I also don’t remember getting clearance to land (I did anyway).

Also, I ran into another problem yesterday. Radar Contact didn’t seem to recognize the destination airport at first (ZBAA - Beijing Capital). Used simbrief to build the flight plan. I was getting closer and closer to the destination and they didn’t tell me to descend. I got about 50 NM away and eventually asked to go to “divert” to ZBAA and they recognized it and then descended and landed fine. In the beginning, I noticed that when I got my clearance, they left out the airport. Not sure what happened, as that never occurred before.

[Ray Proudfoot 8,927]

You’re going to have to live with strange Ai movements. At the time RC was coded there was a fraction of the traffic we have now. Go-around are not handled by RC.

Did frequencies for ZBAA appear in the main RC window when you loaded your plan? If so, then it’s in the database. If not then it’s not there and hence why you weren’t instructed to descend.

Ill need to check which files contain airport data. Possibly a4.csv. See if you have an entry in that for ZBAA.

[agent00729 3]

Yes, with ai it seems there’s always tradeoffs. I can always reload ai after I land.

And I believe so, I just started a flight from ZBAA and all the frequencies were there. No issues this time. Could it be because I increased the simulation rate to 8x last time when I was on the ground before I requested clearance in order to reload the ai?

[Ray Proudfoot 8,927]

The only time I would recommend time acceleration is when you’re at cruise and the path ahead has no sharp deviations. Definitely not on the ground.

[agent00729 3]

Ok good to know, thanks. That was probably it then. What is the reason?

[Ray Proudfoot 8,927]

Asking a complex program to work at eight times its normal speed is asking for trouble especially when it has to read, scan and calculate all the data in the table containing Ai traffic. This is especially critical when departing busy airports as airborne data is generated as soon as the wheels leave the ground.

Make sure any acceleration is switched off before you get within 20nm of the ToD.

A maximum of x4 is recommended and no higher.

[agent00729 3]

Great, thanks for all the help.

[agent00729 3]

Sorry, just one more question! Is it normal to have the sim crash when doing a second leg in Radar Contact? I’ve noticed this both times I’ve used Radar Contact on a second leg (the most recent of which I just did). At the beginning of the return trip back to ZBAA, I quit RC4, then restarted it (without restarting the sim) and loaded the return trip flight plan. The sim CTD 50 nm from ZBAA, just as I was leaving the frequency for weather. This is the second time this has happened, and only has happened on second leg trips. 
 

Sorry for so many questions! I’m new to RC4! Loving it so far, just want to make sure I’m using it correctly.

[Ray Proudfoot 8,927]

It’s always a good idea if you’re going to fly a second leg to exit P3D and restart it. Save the scenario so you can load it from the Scenario screen. There will be things internal in the sim that need resetting.

You have to end RC4 of course since there is an option to hear your critique before quitting or quitting without hearing it.

[agent00729 3]

Sounds good! Thanks for all the help